The Fern Lover's Companion
A Guide for the Northeastern States and Canada
GEORGE HENRY TILTON, A.M.
"This world's no blot for us Nor blank; it means intensely and it means good To find its meaning is my meat and drink."
To Alice D. Clark, engraver of these illustrations, who has spared no pains to promote the artistic excellence of this work, and to encourage its progress, these pages are dedicated with the high regards of THE AUTHOR.
List of Illustrations Preface Introduction Key to Genera Classification of Ferns The Polypodies The Bracken Group: Bracken Cliff Brakes Rock Brake The Lip Ferns (Cheilanthes) The Cloak Fern (Notholaena) The Chain Ferns The Spleenworts: The Rock Spleenworts. Asplenium The Large Spleenworts. Athyrium Hart's Tongue and Walking Leaf The Shield Ferns: Christmas and Holly Fern Marsh Fern Tribe The Beech Ferns The Fragrant Fern The Wood Ferns The Bladder Ferns The Woodsias The Boulder Fern (Dennstaedtia) Sensitive and Ostrich Ferns The Flowering Ferns (Osmunda) Curly Grass and Climbing Fern Adder's Tongue The Grape Ferns: Key to the Grape Fern Moonwort Little Grape Fern Lance-leaved Grape Fern Matricary Fern Common Grape Fern Rattlesnake Fern Filmy Fern Noted Fern Authors Fern Literature Time List for Fruiting of Ferns Glossary Note: Meaning of Genus and Species Checklist
LIST OF ILLUSTRATIONS
A Fern Lover Prothallium Diagram Pinnate Frond Bipinnate Frond Pinnatifid Frond Spore Cases Linen Tester Curly Grass. Schizaea Cinnamon Fern. Osmunda cinnamomea Sensitive Fern. Onoclea sensibilis Ostrich Fern. Onoclea Struthiopteris Interrupted Fern. Osmunda Claytoniana Climbing Fern. Lygodium Flowering Fern. Osmunda regalis spectabilis Adder's Tongue. Ophioglossum Grape Fern. Botrychium Polypody. Polypodium Beech Fern. Phegopteris Cloak Fern. Notholaena Filmy Fern. Trichomanes Bracken. Pteris Maidenhair. Adiantum Cliff Brake. Pellaea Lip Fern. Cheilanthes Rock Brake. Cryptogramma Chain Fern. Woodwardia Shield Fern. Polystichum Wood Fern. Aspidium Bladder Fern. Cystopteris Woodsia Hayscented Fern. Dennstaedtia Hart's Tongue. Scolopendrium Walking Fern. Camptosorus Asplenium Type Athyrium Type Sporangia of the Five Families Indusium Common Polypody. Polypodium vulgare Sori of Polypody Polypody in mass (Greenwood) Gray Polypody. Polypodium incanum Brake. Bracken. Sterile Frond Bracken. Fertile Frond Bracken, var. pseudocaudata Spray of Maidenhair Sori of Maidenhair Maidenhair. Adiantum pedatum Alpine Maidenhair Venus-Hair Fern. Adiantum capillus-veneris Purple Cliff Brake. Pellaea atropurpurea Dense Cliff Brake. Cryptogramma densa Slender Cliff Brake. Cryptogramma Stelleri Parsley Fern. Cryptogramma acrostichoides Alabama Lip Fern. Cheilanthes alabamensis Hairy Lip Fern. Cheilanthes lanosa Slender Lip Fern. Cheilanthes Feei Pinnae of Slender Lip Fern Powdery Cloak Fern. Notholaena dealbata Common Chain Fern. Woodwardia virginica Net-veined Chain Fern. Woodwardia areolata The Spleenworts Pinnatifid Spleenwort. Asplenium pinnatifidum Scott's Spleenwort. Asplenium ebenoides Green Spleenwort. Asplenium viride Maidenhair Spleenwort. Asplenium Trichomanes Maidenhair Spleenwort. Asplenium Trichomanes (Fernery) Ebony Spleenwort. Asplenium platyneuron Bradley's Spleenwort. Asplenium Bradleyi Mountain Spleenwort. Asplenium montanum Rue Spleenwort. Asplenium Ruta-muraria Rootstock of Lady Fern (Two parts) Sori of Lady Fern. Athyrium angustum Varieties of Lady Fern Lowland Lady Fern. Athyrium asplenioides Silvery Spleenwort. Athyrium acrostichoides Narrow-leaved Spleenwort. Athyrium angustifolium Pinnae and Sori of Athyrium angustifolium Sori of Scolopendrium vulgare Hart's Tongue. Scolopendrium vulgare Walking Fern. Camptosorus rhizophyllus Christmas Fern. Polystichum acrostichoides Varieties of Christmas Fern Braun's Holly Fern. Polystichum Braunii Holly Fern. Polystichum Lonchitis Marsh Fern. Aspidium Thelypteris Marsh Fern, in the mass Massachusetts Fern. Aspidium simulatum New York Fern. Aspidium noveboracense Sori of Aspidium noveboracense Pinnae and Sori of Aspidium noveboracense Oak Fern. Phegopteris Dryopteris Northern Oak Fern. Phegopteris Robertiana Broad Beech Fern. Aspidium hexagonoptera Long Beech Fern. Aspidium polypedioides Fragrant Fern. Aspidium fragrans Marginal Shield Fern. Aspidium marginale Crown of Fronds of Aspidium marginale Sori of Aspidium marginale Male Fern. Aspidium Filix-mas Aspidium Filix-mas and details Goldie's Shield Fern. Aspidium Goldianum Aspidium Goldianum, in the mass Crested Shield Fern. Aspidium cristatum Crested Shield Fern. Aspidium cristatum (No. 2) Clinton's Shield Fern. Aspidium cristatum var. Clintonianum Crested Marginal Fern. Aspidium cristatum x marginale Aspidium cristatum x marginale, in the mass Boott's Shield Fern. Aspidium Boottii Spinulose Shield Fern. Aspidium spinulosum Aspidium spinulosum var. intermedium Aspidium spinulosum var. americanum Bulblet Bladder Fern. Cystopteris bulbifera Cystopteris bulbifera with sprouting bulb Fragile Bladder Fern. Cystopteris fragilis Rusty Woodsia. Woodsia ilvensis Northern Woodsia. Woodsia alpina Details of Alpine Woodsia Blunt-lobed Woodsia. Woodsia obtusa Smooth Woodsia. Woodsia glabella Hayscented Fern. Dennstaedtia punctilobula Forked variety of Dennstaedtia punctilobula Field View of Dennstaedtia punctilobula Pinnae and Sori of Dennstaedtia punctilobula Meadow View of Sensitive Fern Obtusilobata Forms of Sensitive Fern, Leaf to Fruit Sori of Sensitive Fern Sensitive Fern. Onoclea sensibilis Sensitive Fern, Fertile and Sterile Fronds on Same Plant Ostrich Fern. Onoclea Struthiopteris. Fertile Fronds Ostrich Fern. Sterile Fronds Sori and Sporangia of Ostrich Fern Royal Fern. Osmunda regalis spectabilis Sori of Royal Fern Interrupted Fern. Osmunda Claytoniana Interrupted Fern. Fertile Pinnules Spread Open Cinnamon Fern. Osmunda cinnamomea Cinnamon Fern. Leaf Gradations Two Varieties of Cinnamon Fern Osmunda cinnamomea glandulosa Curly Grass. Schizaea pusilla Sporangia of Curly Grass Climbing Fern. Lygodium palmatum Adder's Tongue. Ophioglossum vulgatum Moonwort. Botrychium Lunaria Moonwort, Details Little Grape Fern. Botrychium simplex Lance-leaved Grape Fern. Botrychium lanceolatum Matricary Grape Fern. Botrychium ramosum Common Grape Fern. Botrychium obliquum Botrychium obliquum var. dissectum Botrychium obliquum var. oneidense Ternate Grape Fern. Botrychium ternatum var. intermedium Ternate Grape Fern. B. ternatum var. intermedium Rattlesnake Fern. Botrychium virginianum Filmy Fern. Trichomanes Boschianum Fruiting Pinnules of Filmy Fern Crosiers Noted Fern Authors Spray of the Bulblet Bladder Fern
A lover of nature feels the fascination of the ferns though he may know little of their names and habits. Beholding them in their native haunts, adorning the rugged cliffs, gracefully fringing the water-courses, or waving their stately fronds on the borders of woodlands, he feels their call to a closer acquaintance. Happy would he be to receive instruction from a living teacher: His next preference would be the companionship of a good fern book. Such a help we aim to give him in this manual. If he will con it diligently, consulting its glossary for the meaning of terms while he quickens his powers of observation by studying real specimens, he may hope to learn the names and chief qualities of our most common ferns in a single season.
Our most productive period in fern literature was between 1878, when Williamson published his "Ferns of Kentucky," and 1905, when Clute issued, "Our Ferns in Their Haunts." Between these flourished D.C. Eaton, Davenport, Waters, Dodge, Parsons, Eastman, Underwood, A.A. Eaton, Slosson, and others. All their works are now out of print except Clute's just mentioned and Mrs. Parsons' "How to Know the Ferns." Both of these are valuable handbooks and amply illustrated. Clute's is larger, more scholarly, and more inclusive of rare species, with an illustrated key to the genera; while Mrs. Parsons' is more simple and popular, with a naive charm that creates for it a constant demand.
We trust there is room also for this unpretentious, but progressive, handbook, designed to stimulate interest in the ferns and to aid the average student in learning their names and meaning. Its geographical limits include the northeastern states and Canada. Its nomenclature follows in the main the seventh edition of Gray's Manual, while the emendations set forth in Rhodora, of October, 1919, and also a few terms of later adoption are embodied, either as synonyms or substitutes for the more familiar Latin names of the Manual, and are indicated by a different type. In every case the student has before him both the older and the more recent terms from which to choose. However, since the book is written primarily for lovers of Nature, many of whom are unfamiliar with scientific terms, the common English names are everywhere given prominence, and strange to say are less subject to change and controversy than the Latin. There is no doubt what species is meant when one speaks of the Christmas fern, the ostrich fern, the long beech fern, the interrupted fern, etc. The use of the common names will lead to the knowledge and enjoyment of the scientific terms.
A friend unfamiliar with Latin has asked for pointers to aid in pronouncing the scientific names of ferns. Following Gray, Wood, and others we have marked each accented syllable with either the grave (') or acute () accent, the former showing that the vowel over which it stands has its long sound, while the latter indicates the short or modified sound. Let it be remembered that any syllable with either of these marks over it is the accented syllable, whose sound will be long or short according to the slant of the mark.
We have appropriated from many sources such material as suited our purpose. Our interest in ferns dates back to our college days at Amherst, when we collected our first specimens in a rough, bushy swamp in Hadley. We found here a fine colony of the climbing fern (Lygodium). We recall the slender fronds climbing over the low bushes, unique twiners, charming, indeed, in their native habitat. We have since collected and studied specimens of nearly every New England fern, and have carefully examined most of the other species mentioned in this book. By courtesy of the librarian, Mr. William P. Rich, we have made large use of the famous Davenport herbarium in the Massachusetts Horticultural library, and through the kindness of the daughter, Miss Mary E. Davenport, we have freely consulted the larger unmounted collection of ferns at the Davenport homestead, at Medford, finding here a very large and fine assortment of Botrychiums, including a real B. ternatum from Japan.
[Footnote 1: Recently donated to the Gray Herbarium.]
For numerous facts and suggestions we are indebted to the twenty volumes of the Fern Bulletin, and also to its able editor, Mr. Willard N. Clute. To him we are greatly obligated for the use of photographs and plates, and especially for helpful counsel on many items. We appreciate the helpfulness of the American Fern Journal and its obliging editor, Mr. E.J. Winslow. To our friend, Mr. C.H. Knowlton, our thanks are due for the revision of the checklist and for much helpful advice, and we are grateful to Mr. S.N.F. Sanford, of the Boston Society of Natural History, for numerous courtesies; but more especially to Mr. C.A. Weatherby for his expert and helpful inspection of the entire manuscript.
The illustrations have been carefully selected; many of them from original negatives bequeathed to the author by his friend, Henry Lincoln Clapp, pioneer and chief promoter of school gardens in America. Some have been photographed from the author's herbarium, and from living ferns. A few are from the choice herbarium of Mr. George E. Davenport, and also a few reprints have been made from fern books, for which due credit is given. The Scott's spleenwort, on the dedication page, is reprinted from Clute's "Our Ferns in Their Haunts."
Thoreau tells us, "Nature made a fern for pure leaves." Fern leaves are in the highest order of cryptogams. Like those of flowering plants they are reinforced by woody fibres running through their stems, keeping them erect while permitting graceful curves. Their exquisite symmetry of form, their frequent finely cut borders, and their rich shades of green combine to make them objects of rare beauty; while their unique vernation and method of fruiting along with their wonderful mystery of reproduction invest them with marked scientific interest affording stimulus and culture to the thoughtful mind. By peculiar enchantments these charming plants allure the ardent Nature-lover to observe their haunts and habits.
"Oh, then most gracefully they wave In the forest, like a sea, And dear as they are beautiful Are these fern leaves to me."
As a rule the larger and coarser ferns grow in moist, shady situations, as swamps, ravines, and damp woods; while the smaller ones are more apt to be found along mountain ranges in some dry and even exposed locality. A tiny crevice in some high cliff is not infrequently chosen by these fascinating little plants, which protect themselves from drought by assuming a mantle of light wool, or of hair and chaff, with, perhaps, a covering of white powder as in some cloak ferns—thus keeping a layer of moist air next to the surface of the leaf, and checking transpiration.
Some of the rock-loving ferns in dry places are known as "resurrection" ferns, reviving after their leaves have turned sere and brown. A touch of rain, and lo! they are green and flourishing.
Ferns vary in height from the diminutive filmy fern of less than an inch to the vast tree ferns of the tropics, reaching a height of sixty feet or more.
Ferns are propagated in various ways. A frequent method is by perennial rootstocks, which often creep beneath the surface, sending up, it may be, single fronds, as in the common bracken, or graceful leaf-crowns, as in the cinnamon fern. The bladder fern is propagated in part from its bulblets, while the walking leaf bends over to the earth and roots at the tip.
Ferns are also reproduced by spores, a process mysterious and marvellous as a fairy tale. Instead of seeds the fern produces spores, which are little one-celled bodies without an embryo and may be likened to buds. A spore falls upon damp soil and germinates, producing a small, green, shield-shaped patch much smaller than a dime, which is called a prothallium (or prothallus). On its under surface delicate root hairs grow to give it stability and nutriment; also two sorts of reproductive organs known as antheridia and archegonia, the male and female growths analogous to the stamens and pistils in flowers. From the former spring small, active, spiral bodies called antherozoids, which lash about in the moisture of the prothallium until they find the archegonia, the cells of which are so arranged in each case as to form a tube around the central cell, which is called the ooesphere, or egg-cell, the point to be fertilized. When one of the entering antherozoids reaches this point the desired change is effected, and the canal of the archegonium closes. The empty ooesphere becomes the quickened ooesphore whose newly begotten plant germ unfolds normally by the multiplication of cells that become, in turn, root, stem, first leaf, etc., while the prothallium no longer needed to sustain its offspring withers away.
[Footnote 1: In the accompanying illustration, it should be remembered that the reproductive parts of a fern are microscopic and cannot be seen by the naked eye.]
Fern plants have been known to spring directly from the prothallus by a budding process apart from the organs of fertilization, showing that Nature "fulfills herself in many ways."
[Footnote 2: The scientific term for this method of reproduction is apogamy (apart from marriage). Sometimes the prothallus itself buds directly from the frond without spores, for which process the term apospory is used. (Meaning, literally, without spores.)]
All true ferns come out of the ground head foremost, coiled up like a watch-spring, and are designated as "fiddle-heads," or crosiers. (A real crosier is a bishop's staff.) Some of these odd young growths are covered with "fern wool," which birds often use in lining their nests. This wool usually disappears later as the crosier unfolds into the broad green blade. The development of plant shoots from the bud is called vernation (Latin, ver meaning spring), and this unique uncoiling of ferns, "circinnate vernation."
The veins of a fern are free, when, branching from the mid-vein, they do not connect with each other, and simple when they do not fork. When the veins intersect they are said to anastomose (Greek, an opening, or network), and their meshes are called areolae or areoles (Latin, areola, a little open space).
EXPLANATION OF TERMS
A frond is said to be pinnate (Latin, pinna, a feather), when its primary divisions extend to the rachis, as in the Christmas fern (Fig. 1). A frond is bipinnate (Latin, bis, twice) when the lobes of the pinnae extend to the midvein as in the royal fern (Fig. 2). These divisions of the pinnae are called pinnules. When a frond is tripinnate the last complete divisions are called ultimate pinnules or segments. A frond is pinnatifid when its lobes extend halfway or more to the rachis or midvein as in the middle lobes of the pinnatifid spleenwort (Fig. 3). The pinnae of a frond are often pinnatifid when the frond itself is pinnate; and a frond may be pinnate in its lower part and become pinnatifid higher up as in the pinnatifid spleenwort just mentioned (Fig. 3).
The divisions of a pinnatifid leaf are called segments; of a bipinnatifid or tripinnatifid leaf, ultimate segments.
SPORANGIA AND FRUIT DOTS
Fern spores are formed in little sacs known as spore-cases or sporangia (Fig. 4). They are usually clustered in dots or lines on the back or margin of a frond, either on or at the end of a small vein, or in spike-like racemes on separate stalks. Sori (singular sorus, a heap), or fruit dots may be naked as in the polypody, but are usually covered with a thin, delicate membrane, known as the indusium (Greek, a dress, or mantle). The family or genus of a fern is often determined by the shape of its indusium; e.g., the indusium of the woodsias is star-shaped; of the Dicksonias, cup-shaped; of the aspleniums, linear; of the wood ferns, kidney-shaped, etc.
In many ferns the sporangia are surrounded in whole or in part by a vertical, elastic ring (annulus) reminding one of a small, brown worm closely coiled (Fig. 4). As the spores mature, the ring contracts and bursts with considerable force, scattering the spores. The spores of the different genera mature at different times from May to September. A good time to collect ferns is just before the fruiting season. (For times of fruiting see individual descriptions or chronological chart on page 220.)
The following hints may be helpful to the young collector:
1. A good lens with needles for dissecting is very helpful in examining the sori, veins, glands, etc., as an accurate knowledge of any one of these items may aid in identifying a given specimen. Bausch and Lomb make a convenient two-bladed pocket glass for about two dollars.
[Footnote 1: In the linen tester here figured (cost $1.50) the lens is mounted in a brass frame which holds it in position, enabling the dissector to use both hands. A tripod lens will also be found cheap and serviceable.]
2. Do not exterminate or weaken a fern colony by taking more plants than it can spare. In small colonies of rare ferns take a few and leave the rest to grow. It is decidedly ill-bred to rob a locality of its precious plants. Pick your fern leaf down close to the root-stock, including a portion of that also, if it can be spared. Place your fronds between newspaper sheets and lay "dryers" over them (blotting paper or other absorbent paper). Cover with a board or slat frame, and lay on this a weight of several pounds, leaving it for twenty-four hours; if the specimens are not then cured, change the dryers. Mount the prepared specimens on white mounting sheets. The regulation size is 16-1/2 by 11-1/2 inches. The labels are usually 3-3/4 by 1-3/4 inches. A sample will suggest the proper inscription.
HERBARIUM OF JOHN DOE Ophioglossum vulgatum, L. (Adder's Tongue) Willoughby Lake, Vt. August 19, 1911. Wet meadow. Coll. X.Y.Z. Rather common but often overlooked
Place the label at the lower right-hand corner of the sheet, which is now ready to be laid in the genus cover, usually of manila paper 16-1/2 by 12 inches.
It is well to jot down important memoranda at the time of collecting. This is the method in use at the Gray Herbarium in Cambridge. It can, of course, be modified to suit one's own taste or convenience. The young collector can begin by simply pressing his specimens between the leaves of a book, the older and coarser the better; and he can mount them in a blank book designed for the purpose, or if he has only a common blank book, he can cut out some of the leaves, alternately with others left in place, as is often done with a scrap book, that when the book is full it may not be crowded at the back. Or he can use sheets of blank paper of any uniform size and mount the specimens on these with gummed strips, and then group them, placing those of the same genus together. Such an extemporized herbarium, though crude, will serve for a beginning, while stimulating his interest, and advancing his knowledge of the ferns. Let him collect, press, and mount as many varieties as possible, giving the name with date and place of collecting, etc. Such a first attempt may be kept as a reminder of pleasant hours spent in learning the rudiments of a delightful study.
We cannot insist too strongly upon the necessity of handling and studying the living plant. Every student needs to observe for himself the haunts, habits, and structure of real ferns. We would say to the young student, while familiarizing yourself with the English names of the ferns, do not neglect the scientific names, which often hold the key to their meaning. Repeat over and over the name of each genus in soliloquy and in conversation until your mind instantly associates each fern with its family name—"Adiantum," "Polystichum," "Asplenium," and all the rest. Fix them in the memory for a permanent asset. With hard study and growing knowledge will come growing attachment. How our great expert, Mr. Davenport, loved the ferns! He would handle them with gentle touch, fondly stroke their leaves, and devoutly study their structure, as if inspired by the All-wise Interpreter.
"Move along these shades In gentleness of heart: with gentle hand Touch—for there is a spirit in the woods."
KEY TO THE GENERA
This key, in illustrating each genus, follows the method of Clute in "Our Ferns in Their Haunts," but substitutes other and larger specimens. Five of these are from Waters' "Ferns" by permission of Henry Holt & Co.
As the indusium, which often determines the name of a fern, is apt in some species to wither early, it is important to secure for study not only a fertile frond, but one in as good condition as possible. For convenience the ferns may be considered in two classes.
THOSE WHICH HAVE THE FRUITING PORTION IN GREENISH, BERRY-LIKE STRUCTURES AND NOT ON THE BACK OF FRONDS
A. FRUITING FRONDS WHOLLY FERTILE
(Fertile and sterile fronds entirely unlike)
1. Fruit in a one-sided spike in two ranks; plants very small; sterile fronds thread-like and tortuous.
Curly Grass. Schizaea.
2. Fruit in a club-shaped, brown or cinnamon-colored spike loaded with sporangia; fruit in early spring.
Cinnamon Fern. Osmunda cinnamomea.
3. Fruit in berry-like, greenish structures in a twice pinnate spike, which comes up much later than the broad and coarse pinnatifid sterile fronds.
Wet ground. Sensitive Fern. Onoclea.
4. Fruit in pod-like or necklace-like pinnae; fertile frond pinnate; sterile frond tall, pinnatifid; fruit late.
Ostrich Fern. Onoclea struthiopteris.
B. FRUITING FRONDS PARTLY STERILE
1. Fruiting portion in the middle of the frond; two to four pairs of fertile pinnae.
Interrupted Fern. Osmunda Claytoniana.
2. Fruiting portion at the apex of the frond. Sterile pinnae palmate; rachis twining.
Climbing Fern. Lygodium.
Sterile pinnae pinnate; fronds large, fertile portion green, turning brown, forming a panicle at the top.
Royal Fern. Osmunda regalis.
3. Fruiting portion seemingly on a separate stock a few inches above the sterile.
Sterile part an entire, ovate, green leaf near the middle; fertile part a spike.
Adder's Tongue. Ophioglossum.
Sterile portion more or less divided; fruit in racemes or panicles, rarely in spikes.
Grape Ferns. Moonwort. Botrychium.
THOSE WHICH HAVE THE FRUITING PORTION ON THE BACK OR MARGIN OF FRONDS
A. INDUSIUM WANTING
1. Fruit-dots large, roundish; fronds evergreen. Rock species.
2. Fruit-dots small, roundish; fronds triangular.
Beech Ferns. Phegopteris.
3. Fruit in lines on the margin of the pinnules; under surface of the fronds covered with whitish powder.
Cloak Ferns. Notholaena.
B. INDUSIUM PRESENT
1. Sori on the edge of a pinnule terminating a vein; sporangia at the base of a long, bristle-like receptacle surrounded by a cup-shaped indusium.
Filmy Fern. Trichomanes.
2. Indusium formed by the reflexed margin of the pinnules.
(1) Sporangia on a continuous line; fronds large, ternate; indusium narrow. Bracken. Brake. Pteris.
(2) Sporangia in oblong sori under a reflexed tooth of a pinnule; indusium broad; rachis dark and shining. Maidenhair. Adiantum.
(3) Sori in roundish or elongated masses.
Indusium broad, nearly continuous, fronds mostly smooth, somewhat leathery, pinnate. Rock species. Cliff brakes. Pellaea.
Indusium narrow, seldom continuous, formed by the margin of separate lobes or of the whole pinnules; often inconspicuous, fronds usually hairy. Lip Ferns. Cheilanthes.
Indusium of the reflexed edges, at first reaching to the midrib, or nearly so; later opening out nearly flat; fruiting pinnules pod-like; sterile fronds broad. Rock brakes. Cryptogramma.
3. Indusium never formed of the margin of the frond. Sori various.
(1) Fruit-dots oblong, parallel with the midrib, somewhat sunken in the tissues of the frond. Water-loving species. Chain Ferns. Woodwardia.
(2) Fruit-dots and indusium roundish.
Indusium shield-shaped, fixed by the center. Evergreen glossy ferns in rocky woods. Shield Ferns. Polystichum.
Indusium cordate, fixed by the sinus. Wood Ferns. Aspidium.
Indusium hood-shaped, fixed centrally behind the sorus and arching over it, soon withering, often illusive. Fronds two to three pinnate, very graceful. Moisture-loving species. Bladder Ferns. Cystopteris.
Indusium star-shaped, of a few irregular segments fixed beneath the sorus, often obscure. Mostly small, rock-loving plants, usually rather chaffy, at least at the base, and growing in tufts. Woodsia.
Indusium cup-shaped, fixed beneath the sorus, supported by the tooth of a leaf; sporangia borne in an elevated, globular receptacle open at the top. Fronds finely cut. Hayscented Fern. Dennstaedtia.
(3) Fruit-dots and indusium linear. (But see Athyrium.)
Very long, nearly at right angles to the midrib, double; blade thick oblong-lanceolate, entire; heart-shaped at the base. Hart's Tongue. Scolopendrium.
Shorter and irregularly scattered on the under side of the frond, some parallel to the midrib, others oblique to it, and often in pairs or joined at the ends; blade tapering to a slender tip. Walking Fern. Camptosorus.
Short, straight, mostly oblique to the midrib. Indusium rather narrow, opening toward the midrib, fronds lobed or variously divided. Spleenworts. Asplenium.
Short, indusium usually more or less curved and frequently crossing a vein. The large spleenworts including Lady Fern. Athyrium.
DESCRIPTIVE TEXT OF THE FERNS
In this manual our native ferns are grouped scientifically under five distinct families. By far the largest of these groups, and the first to be treated, is that of the real ferns (Polypodiaceae) with sixty species and several chief varieties. Then follow the flowering ferns (Osmundaceae) with three species; the curly grass and climbing ferns (Schizaeaceae) with two species; the adder's tongue and grape ferns (Ophioglossaceae) with seven species; and the filmy ferns (Hymenophyllaceae) with one species.
Corresponding with these five families, the sporangia or spore cases of ferns have five quite distinct forms on which the families are founded.
1. The Fern Family proper (Polypodiaceae) has the spore cases stalked and bound by a vertical, elastic ring (Fig. 1). The clusters of fruit-dots containing the spore cases may be open and naked as in polypody (Fig. 2), or covered by an indusium, as in the shield ferns (Fig. 3).
2. The Royal Fern Family (Osmunda) has the spore cases stalked with only a rudimentary ring on one side, which opens longitudinally (Fig. 4).
3. The Climbing Fern Family (Lygodium, Schizaea) has the spore cases sessile in rows; they are small, nut-like bodies with the elastic ring around the upper portion (Fig. 5).
[Footnote 1: These figures are enlarged.]
4. The Adder's Tongue Family (Ophioglossum, Botrychium) has simple spore cases without a ring, and discharges its spores through a transverse slit (Fig. 6).
5. The Filmy Fern Family (Trichomanes) has the spore cases along a bristle-like receptacle and surrounded by an urn-shaped, slightly two-lipped involucre; ring transverse and opening vertically (Fig. 7).
THE FERN FAMILY PROPER OR REAL FERNS
Green, leafy plants whose spores are borne in spore-cases (sporangia), which are collected in dots or clusters (fruit-dots or sori) on the back of the frond or form lines along the edge of its divisions. Sporangia surrounded by vertical, elastic rings bursting transversely and scattering the spores. Fruit-dots (sori) often covered, at least when young, by a membrane called the indusium. Spores brown.
1. POLYPODY. Polypodium
(From the Greek meaning many-footed, alluding to the branching rootstocks.)
Simple ferns with stipes articulated to the creeping rootstocks, which are covered with brown, chaffy scales. Fruit-dots round, naked, arranged on the back of the frond in one or more rows each side of the midrib. Sporangia pedicelled, provided with a vertical ring which bursts transversely. A large genus with about 350 species, widely distributed, mostly in tropical regions.
(1) COMMON POLYPODY. Polypodium vulgare
Fronds somewhat leathery in texture, evergreen, four to ten inches tall, smooth, oblong, and nearly pinnate. The large fruit-dots nearly midway between the midrib and the margin, but nearer the margin.
Common everywhere on cliffs, usually in half shade, and may at times spring out of decaying logs or the trunks of trees. As the jointed stipes, harking back to some ancient mode of fern growth, fall away from the rootstocks after their year of greenness, they leave behind a scar as in Solomon's seal. The polypody is a gregarious plant. By intertwining its roots the fronds cling together in "cheerful community," and a friendly eye discovers their beauty a long way off. August. Abounds in every clime, including Europe and Japan.
In transplanting, sections should be cut, not pulled from the matted mass.
Var. cambricum has segments broader and more or less strongly toothed.
Var. cristatum has the segments forked at the ends.
Several other forms are also found.
(2) GRAY OR HOARY POLYPODY
Polypodium incanum. P. polypodioides
Fronds oblong, two to seven inches long, deeply pinnatifid, gray and scurfy underneath with peltate scales having a dark center. Fruit-dots rather small, near the margin and obscured by the chaff.
In appearance the gray polypody is much like the common species, as the Greek ending oides (like) implies. In Florida and neighboring states it often grows on trees; farther north mostly on rocks. Reported as far north as Staten Island. It is one of the "resurrection" ferns, reviving quickly by moisture after seeming to be dead from long drouth. July to September. Widely distributed in tropical America. Often called Tree-Polypody.
THE BRACKEN GROUP
Sporangia near or on the margin of the segments, the reflexed portions of which serve as indusia.
1. BRACKEN OR BRAKE
Pteris aquilina. PTERIDIUM LATIUSCULUM
[Footnote 1: The use of small capitals in the scientific names indicates in part the newer nomenclature which many botanists are inclined to adopt.]
Fronds broadly triangular, ternate, one to three feet high or more, the widely spreading branches twice pinnate, the lower pinnules more or less pinnatifid. Sporangia borne in a continuous line along the lower margin of the ultimate divisions whose reflexed edges form the indusium. (Greek, pteron, a wing, the feathery fronds suggesting the wings of a bird.)
"The heath this night must be my bed, The bracken curtain for my head." SCOTT.
The outlines of the young bracken resemble the little oak fern. It flourishes in thickets and open pastures, often with poor soil and scant shade. It is found in all parts of the world, and is said to be the most common of all our North American ferns. In a cross section of the mature stipe superstition sees "the devil's hoof" and "King Charles in the oak," and any one may see or think he sees the outlines of an oak tree. It was the bracken, or eagle fern, as some call it, which was supposed to bear the mysterious "fern seed," but only on midsummer eve (St. John's eve).
"But on St. John's mysterious night, Confest the mystic fern seed fell."
This enabled its possessor to walk invisible.
"We have the receipt for fern-seed, We walk invisible." SHAKESPEARE.
The word brake or bracken is one of the many plant names from which some of our English surnames are derived, as Brack, Breck, Brackenridge, etc., and fern (meaning the bracken) is seen in Fern, Fearns, Fernham, Fernel, Fernside, Farnsworth, etc. Also, in names of places as Ferney, Ferndale, Fernwood, and others. Although the bracken is coarse and common, it makes a desirable background for rockeries, or other fern masses. The young ferns should be transplanted in early spring with as much of the long, running rootstock as possible.
Var. pseudocaudata has longer, narrower and more distant pinnules, and is a common southern form.
2. MAIDENHAIR. Adiantum
Ferns with much divided leaves and short, marginal sori borne at the ends of free-forking veins, on the under side of the reflexed and altered portion of the pinnules, which serves as an indusium. Stipes and branches of the leaves very slender and polished.
(Greek, unwetted, because drops of water roll off without wetting the leaves.)
(1) COMMON MAIDENHAIR. Adiantum pedatum
A graceful fern of shady glen and rocky woodland, nine to eighteen inches high, the black, shining stalks forked at the top into two equal, recurved branches, the pinnae all springing from the upper side. Pinnules triangular-oblong, bearing short sori on their inwardly reflexed margins which form the indusium.
The maidenhair has a superficial resemblance to the meadow rue, which also sheds water, but it may be known at once by its black, shining stalks with their divisions all borne on one side. It is indeed a most delicate fern, known and admired by every one. The term maidenhair may have been suggested by the black, wiry roots growing from the slender rootstock, or by the dark, polished stems, or, as Clute explains it, "because the black roots, like hair, were supposed, according to the 'doctrine of signatures' to be good for falling hair, and the plant was actually used in the 'syrup of capillaire'[A] (Am. Botanist, November, 1921). While the maidenhair is not very common, it is widely distributed, being found throughout our section, westward to California, and northward to the British Provinces.
"Though the maidenhair has a wide range, and grows abundantly in many localities, it possesses a quality of aloofness which adds to its charm. Its chosen haunts are dim, moist hollows in the woods, or shaded hillsides sloping to the river. In such retreats you find the feathery fronds tremulous on their glistening stalks, and in their neighborhood you find, also, the very spirit of the woods."
[Footnote A: It may be stated that capillaire syrup besides the use here indicated was highly esteemed as a pectoral for the relief of difficult breathing.]
The fern is not hard to cultivate if allowed sufficient moisture and shade. Along with the ostrich fern it makes a most excellent combination in a fern border.
Var. ALEUTICUM, or Alpine Maidenhair. A beautiful northern form especially abundant on the high tableland of the Gaspe Peninsula, Quebec, where it is said to cover hundreds of acres. In the east it is often dwarfed—six to ten inches high, growing in tufts with stout rootstocks, having the pinnules finely toothed instead of rounded and the indusia often lunate, rarely twice as long as broad. (Fernald in Rhodora, November, 1905.) Also found in northern Vermont, and to the northwestward.
(2) THE VENUS-HAIR FERN. Adiantum Capillus-Veneris
Fronds with a continuous main rachis, ovate-lanceolate, twice pinnate below. Pinnules, fan-shaped on slender, black stalks, long, deeply and irregularly incised. Veins extending from the base of the pinnules like the ribs of a fan.
While our common maidenhair is a northern fern, the Venus-hair Fern is confined to the southern states. It is rarely found as far north as Virginia, where it meets, but scarcely overlaps its sister fern. The medicinal properties of Adiantum pedatum were earlier ascribed to the more southern species, which is common in Great Britain, but, like many another old remedy, "the syrup of capillaire" is long since defunct.
3. CLIFF BRAKES. Pellaea
Sporangia borne on the upper part of the free veins inside the margins, in dot-like masses, but may run together, as in the continuous fruiting line of the bracken. Indusium formed of the reflexed margins of the fertile segments which are more or less membranous. (Pellaea, from the Greek pellos, meaning dusky, in allusion to the dark stipes.)
(1) PURPLE CLIFF BRAKE. Pellaea atropurpurea
Stipes dark purple or reddish-brown, polished and decidedly hairy and harsh to the touch, at least on one side. Fronds coriaceous, pale, simply pinnate, or bipinnate below; the divisions broadly linear or oblong, or the sterile sometimes oval, chiefly entire, somewhat heart-shaped, or else truncate at the stalked base. Veins about twice forked. Basal scales extending into long, slender tips, colorless or yellow.
Another name is "the winter brake," as its fronds remain green throughout the winter, especially in its more southern ranges. It grows on rocky ledges with a preference for limestone, and often in full sun. In large and mature fronds its pinnae are apt to be extremely irregular. While its stipes are purplish, its leaves are bluish-green, and its scales light-brown or yellow. Strange to say, this brake of the cliffs thrives in cultivation. Woolson says of it, "This fern is interesting and valuable. It is not only beautiful in design, but unique in color, a dark blue-green emphasizing all the varying tints about it—a first-class fern for indoor winter cultivation. It is a rapid grower, flourishing but a few feet from coal fire or radiator, in a north or south window. It quickly forgives neglect, and if allowed to dry up out of doors or indoors, recovers in due time when put in a moist atmosphere. It makes but one imperative demand, and that is the privilege of standing still. Overzealous culturists usually like to turn things around, but revolving cliffs are not in the natural order of things. The slender black stipes are very susceptible to changes of light and warped and twisted fronds result."
Dry, calcareous rocks, southern New England and westward. Rare. Var. cristata has forked pinnae somewhat crowded toward the summit of the frond. Missouri.
(2) SMOOTH CLIFF BRAKE
Pellaea glabella. Pellaea atropurpurea, var. Bushii
Naked with a few, scattered, spreading hairs, smooth surface and dark polished stipes. Rhizome short with membranous, orange or brown scales having a few bluntish teeth on each edge. Pinnae sub-opposite, divergent, narrowly oblong, obtuse; base truncate, cordate or clasping, occasionally auricled; lower pinnae often with orbicular or cordate pinnules. Sterile pinnae broader, bluish or greenish glaucous above, often crowded to overlapping. The smooth cliff brake has a decidedly northern range, growing from northern Vermont to Missouri, and northwestward, but found rarely, if at all, in southern New England.
(3) DENSE CLIFF BRAKE
Cryptogramma densa. Pellaea densa
Modern botanists are inclined to place the dense cliff brake and the slender cliff brake under the genus Cryptogramma, which is so nearly like Pellaea that one hesitates to choose between them. The word Cryptogramma means in Greek a hidden line, alluding to the line of sporangia hidden beneath the reflexed margin.
The dense cliff brake may be described as follows:
Stipes three to nine inches tall, blades one to three inches, triangular-ovate, pinnate at the summit, and tripinnate below. Segments linear, sharp-pointed, mostly fertile, having the margins entire and recurved, giving the sori the appearance of half-open pods. Sterile fronds sharply serrate. Stipes in dense tufts ("densa") slender, wiry, light-brown.
This rare little fern is a northern species and springs from tiny crevices in rocks, preferring limestone. Like many other rock-loving species, it produces spores in abundance, having no other effective means of spreading, and its fertile fronds are much more numerous than the sterile ones, and begin to fruit when very small. Gaspe and Mt. Albert in the Province of Quebec, Grey County, Ontario, and in the far west.
(4) SLENDER CLIFF BRAKE
Cryptogramma Stelleri. Pellaea gracilis
Fronds (including stipes) three to six inches long, thin and slender with few pinnae. The lower pinnae pinnately parted into three to five divisions, those of the fertile fronds oblong or linear-oblong; those of the sterile, obovate or ovate, crenulate, decurrent at the base. Confined to limestone rocks. Quebec and New Brunswick, to Vermont, Connecticut, Pennsylvania, and to the northwest.
We have collected this dainty and attractive little fern on the limestone cliffs of Mt. Horr, near Willoughby Lake, Vt. It grew in a rocky grotto whose sides were kept moist by dripping water. How we liked to linger near its charming abode high on the cliff! And we liked also to speak of it by its pleasing, simple name, "Pellaea gracilis," now changed for scientific reasons, but we still like the old name better.
(5) THE ROCK BRAKE. PARSLEY FERN
Sterile and fertile fronds very dissimilar; segments of the fertile, linear and pod-like; of the sterile, ovate-oblong, obtuse, and toothed. The plants spring from crevices of rocks and are from six to eight inches high. Stipes of the fertile fronds are about twice as long as the sterile, making two tiers of fronds.
The parsley fern is the typical species of the genus Cryptogramma. The indusium is formed of the altered margin of the pinnule, at first reflexed to the midrib, giving it a pod-like appearance, but at length opening out flat and exposing the sporangia. Clute, speaking of this fern as "the rock brake," calls it a border species, as its home is in the far north—Arctic America to Lake Huron, Lake Superior, Colorado and California.
4. LIP FERNS. Cheilanthes
Mostly small southern ferns growing on rocks, pubescent or tomentose with much divided leaves. Sori at the end of the veins at first small and roundish, but afterwards more or less confluent. The indusium whitish and sometimes herbaceous, formed of the reflexed margin of the lobes or of the whole pinnule. Veins free, but often obscure. Most of the ferns of this genus grow in dry, exposed situations, where rain is sometimes absent for weeks and months. For this reason they protect themselves by a covering of hairs, scales or wool, which hinders the evaporation of water from the plant by holding a layer of more or less saturated air near the surface of the frond. (In Greek the word means lip flower, alluding to the lip-like indusia.)
(1) ALABAMA LIP FERN. Cheilanthes alabamensis
Fronds smooth, two to ten inches long, lanceolate, bipinnate. Pinnae numerous, oblong-lanceolate, the lower usually smaller than those above. Pinnules triangular-oblong, mostly acute, often auricular or lobed at the base. Indusia pale, membranous and continuous except between the lobes. Stipes black, slender and tomentose at the base.
This species of lip fern may be distinguished from all the others within our limits by its smooth pinnae. On rocks—mountains of Virginia to Kentucky, and Alabama, and westward to Arizona.
(2) HAIRY LIP FERN. Cheilanthes lanosa, C. vestita
Fronds twice pinnate, lanceolate with oblong, pinnatifid pinnules; seven to fifteen inches tall, slender and rough with rusty, jointed hairs. Pinnae triangular-ovate, usually distant, the ends of the rounded lobes reflexed and forming separate involucres which are pushed back by the ripening sporangia.
This species like the other lip ferns is fond of rocks, springing from clefts and ledges. While hairy it is much less tomentose than the two following species. Unlike most of the rock-loving ferns this species is not partial to limestone, but grows on other rocks as well. It has been found as far north as New Haven, Conn., also near New York, and in New Jersey, Georgia, and westward to Wyoming and southward.
(3) WOOLLY LIP FERN. Cheilanthes tomentosa
Fronds eight to eighteen inches long, lanceolate-oblong, tripinnate. Pinnae and pinnules ovate-oblong, densely woolly especially beneath, with slender, whitish, obscurely jointed hairs. Of the ultimate segments the terminal one is twice as long as the others. Pinnules distant, the reflexed, narrow margin forming a continuous, membranous indusium. Stipe stout, dark brown, densely woolly.
By donning its thick coat of wool this species is prepared to grow in the most exposed situations of the arid southwest. It is said to be the "rarest, tallest and handsomest of the lip ferns."
Mountains of Virginia and Kentucky to Georgia, and west to Missouri, Texas and Arizona.
(4) SLENDER LIP FERN
Cheilanthes Feei, C. lanuginosa
Stipes densely tufted, slender, at first hairy, dark brown, shining. Fronds three to eight inches long, ovate-lanceolate, with thickish, distinctly articulated hairs, twice or thrice pinnate. Pinnae ovate, the lowest deltoid. Pinnules divided into minute, densely crowded segments, the herbaceous margin recurved and forming an almost continuous indusium.
The slender lip fern, known also as Fee's fern, is much the smallest of the lip ferns, averaging, Clute tells us, "but two inches high." This is only one-third as tall as the woolly lip fern and need not be mistaken for it. The fronds form tangled mats difficult to unravel. It grows on dry rocks and cliffs—Illinois and Minnesota to British Columbia, and south to Texas, New Mexico and Arizona.
5. CLOAK FERN. Notholaena
Small ferns with fruit-dots borne beneath the revolute margin of the pinnules, at first roundish, but soon confluent into a narrow band without indusium. Veins free. Fronds one to several times pinnate, the lower surface hairy, or tomentose or powdery. Includes about forty species, mostly American, but only one within our limits. (Greek name means spurious cloak, alluding to the rudimentary or counterfeit indusium.)
(1) POWDERY CLOAK FERN. Notholaena dealbata
Fronds two to six inches long, triangular-ovate, acute, broadest at the base, tripinnate. Stalks tufted, wiry, shining, dark brown. Upper surface of the very small segments green, smooth, the lower densely coated with a pure, white powder; hence, the specific name dealbata, which means whitened. Sori brown at length; veins free.
There are several species of cloak ferns, but only one within our limits. The dry, white powder which covers them doubtless is designed to protect them from too rapid evaporation of moisture, as they all inhabit dry and sunny places. This delicate rock-loving fern is found in the clefts of dry limestone rocks in Missouri, Kansas, Colorado, and southwestward.
THE CHAIN FERNS. Woodwardia
Large and somewhat coarse ferns of swampy woods with pinnate or nearly two-pinnate fronds, and oblong or linear fruit-dots, arranged in one or more chain-like rows, parallel to and near the midribs. Indusium fixed by its outer margin to a veinlet and opening on the inner side. In our section there are two species. (Named for Thomas J. Woodward, an English botanist.)
(1) THE COMMON CHAIN FERN. Woodwardia virginica
Sterile and fertile fronds similar in outline, two to four feet high, once pinnate, the pinnae deeply incised with oblong segments. Fruit-dots oblong in chain-like rows along the midrib both of the pinnae and the lobes, confluent when ripe. Veins forming narrow rows of net-like spaces (areoles) beneath the fruit-dots, thence free to the margin. The spores ripen in July.
The sterile fronds resemble those of the cinnamon fern, but the latter grow in crowns, with a single frond in the center, while the fronds of the chain fern rise singly from the creeping rootstock, which sends them up at intervals all summer. The sori are borne on the backs of fertile fronds. There are usually more sterile than fertile blades, especially in dense shade. We have waded repeatedly through a miry swamp in Melrose, Mass., where the wild calla flourishes along with the blueberry and other swamp bushes, and have found the chain fern in several shaded spots, but every frond was sterile. It is said that when exposed to the sun it always faces the south. Swamps, Maine to Florida, especially along the Atlantic Coast, and often in company with the narrow-leaved species.
(2) NET-VEINED CHAIN FERN
NARROW-LEAVED CHAIN FERN
Woodwardia areolata. W. angustifolia
Root stocks creeping and chaffy. Sterile and fertile fronds unlike; sterile ones nine to twelve inches tall, deltoid-ovate. Broadest at the base, with lanceolate, serrulate divisions united by a broad wing. Veins areolate; fertile fronds taller, twelve to twenty inches high with narrowly linear divisions, the areoles and fruit-dots in a single row each side of the secondary midrib, the latter sunk in the tissues.
This species is less common than the Virginia fern, but they often grow near each other. We have collected both in the Blue Hill reservation near Boston, and both have been found in Hingham, Medford, and Reading, and doubtless in other towns along the coast. Mrs. Parsons speaks of finding them in the flat, sandy country near Buzzard's Bay. The net-veined species has some resemblance to the sensitive fern, but in the latter the spore cases are shut up in small pods formed by the contracting and rolling up of the lobes, whereas the chain fern bears its sori on the under side of long, narrow pinnae. Besides, the sterile fronds of the latter have serrulate segments. As in the sensitive fern there are many curious gradations between the fertile and sterile fronds, both in shape and fruitfulness. Waters calls them the "obtusilobata form."
A. THE ROCK SPLEENWORTS. Asplenium
Small, evergreen ferns. Fruit-dots oblong or linear, oblique, separate when young. Indusium straight or rarely curved, fixed lengthwise on the upper side of a fertile veinlet, opening toward the midrib. Veins free. Scales of rhizome and stipes narrow, of firm texture and with thick-walled cells.
(1) PINNATIFID SPLEENWORT. Asplenium pinnatifidum
Fronds four to six inches long, lanceolate, pinnatifid or pinnate near the base, tapering above into a slender prolongation. Lobes roundish-ovate, or the lower pair acuminate. Fruit-dots irregular, numerous. Stipes tufted, two to four inches long, brownish beneath, green above.
Although this fern, like all the small spleenworts, is heavily fruited, it is extremely rare. It is found as far north as Sharon, Conn., thence southward to Georgia, to Arkansas and Missouri. On cliffs and rocks. Resembles the walking fern, and its tip sometimes takes root.
(2) SCOTT'S SPLEENWORT. Asplenium ebenoides
Fronds four to ten inches long, broadly lanceolate, pinnatifid or pinnate below, tapering to a prolonged and slender apex. Divisions lanceolate from a broad base. Fruit-dots straight or slightly curved. Stipe and rachis brown.
Resembles the last, and like that has been known to root at the tip. It is a hybrid between the walking fern and the ebony spleenwort, as proved by Miss Margaret Slosson, and may be looked for in the immediate vicinity of its parents. It was discovered by R.R. Scott, in 1862, at Manayunk, Pa., a suburb of Philadelphia, and described by him in the Gardener's Monthly of September, 1865. Vermont to Alabama, Missouri, and southward. Rare, but said to be plentiful in a deep ravine near Havana, Ala.
(3) GREEN SPLEENWORT. Asplenium viride
Fronds two to ten inches long, linear, pinnate, pale green. Pinnae roundish-ovate, crenate, with indistinct and forking midveins. Stalks tufted, short, brownish below, green above. Rachis green.
Discovered at Smuggler's Notch, Mt. Mansfield, Vt., by C.G. Pringle in 1876. Found sparingly at Willoughby Lake, high on the cliffs of Mt. Horr. This rare and delicate little plant bears a rather close resemblance to the maidenhair spleenwort, which, however, has dark stipes instead of green.
Northern New England, west and northwest on shaded limestone rocks.
(4) MAIDENHAIR SPLEENWORT. Asplenium Trichomanes
Stipes densely tufted, purple-brown, shining. Fronds three to eight inches long, linear, dark green, rather rigid. Pinnae roundish-oblong or oval, entire or finely crenate, attached at the base by a narrow point. Midveins forking and evanescent.
Not very common, but distributed almost throughout North America. May be looked for wherever there are ledges, as it does not require limestone. July.
(5) SMALL SPLEENWORT
Asplenium parvulum. A. resiliens
Fronds four to ten inches tall, narrowly linear, rather firm, erect. Pinnae opposite, oblong, entire or finely crenate, and auricled at the base. Stipes and rachis black and shining. Midveins continuous.
This small fern is a southern species half way between the maidenhair and ebony spleenworts, but rather more like the latter from which it differs in being smaller and thicker, and in having the fertile and sterile fronds of the same size. Mountains of Virginia to Kansas and southward.
(6) EBONY SPLEENWORT
Asplenium platyneuron. A. ebeneum
Fronds upright, eight to eighteen inches high, linear-lanceolate, the fertile ones much taller, and pinnate. Pinnae scarcely an inch long, the lower ones very much shorter, alternate, spreading, finely serrate or incised, the base auricled. Sori numerous, rather near the midvein, stipe and rachis lustrous brown. ("Ebony.")
This rigidly upright but graceful fern flourishes in rocky, open woods, and on rich, moist banks, often in the neighborhood of red cedars. Having come upon it many times in our rambles, we should say it was not uncommon.
A lightly incised form of the pinnae has been described as var. serratum. A handsome form discovered in Vermont in 1900 by Mrs. Horton and named Hortonae (also called incisum) has plume-like fronds with the pinnae cut into oblique lobes, which are coarsely serrate.
(7) BRADLEY'S SPLEENWORT. Asplenium Bradleyi
Fronds oblong-lanceolate, pinnate, three to ten inches long. Pinnae oblong-ovate, obtuse, incised or pinnatifid into oblong, toothed lobes. The basal pinnae have broad bases, and blunt tips and are slightly stalked. Stipes and rachis dark brown and the sori short, near the midrib.
A rare and beautiful fern growing on rocks preferring limestone and confined mostly to the southern states. Newburg, N.Y., to Kentucky and Alabama, westward to Arkansas.
(8) MOUNTAIN SPLEENWORT. Asplenium montanum
Fronds ovate-lanceolate from a broad base, two to eight inches long, somewhat leathery, pinnate. Pinnae ovate-oblong, the lowest pinnately cleft into oblong or ovate cut-toothed lobes, the upper ones less and less divided. Rachis green, broad, and flat.
Small evergreen ferns of a bluish-green color, growing in the crevices of rocks and cliffs. Connecticut to Ohio, Kentucky, Arkansas and southwest. July. Rare. Williams, in his "Ferns of Kentucky," says of this species, "Common on all sandstone cliffs and specimens are large on sheltered rocks by the banks of streams."
(9) RUE SPLEENWORT. Asplenium Ruta-muraria
Fronds evergreen, small, two to seven inches long, deltoid-ovate, two to three pinnate below, simply pinnate above, rather leathery in texture. Divisions few, stalked, from cuneate to roundish-ovate, toothed or incised at the apex. Veins forking. Rachis and stipe green. Sori few, soon confluent.
This tiny fern grows from small fissures in the limestone cliffs, and is rather rare in this country; but in Great Britain it is very common, growing everywhere on walls and ruins. From Mt. Toby, Mass., and Willoughby Mountain, Vt., to Michigan, Missouri, Kentucky and southward.
B. THE LARGE SPLEENWORTS. Athyrium
The following species, which are often two to three feet high and grow in rich soil, are quite different in appearance and habits from the small rock spleenworts just described. Some botanists have kept them in the genus Asplenium because their sori are usually rather straight or only slightly curved, but others are inclined to follow the practice of the British botanists and put them into a separate group under Athyrium. Nearly all agree that the lady fern, with its variously curved sori, should be placed here, and many others would place the silvery spleenwort in the same genus, partly because of its frequently doubled sori. In regard to the last member of the group, the narrow-leaved spleenwort, there is more doubt. The sori taken separately would place it with the Aspleniums, but considering its size, structure, habits of growth and all, it seems more closely allied to the two larger ferns than to the little rock species. We shall group the three together as the large spleenworts, or for the sake of being more definite adopt Clute's felicitous phrase.
THE LADY FERN AND ITS KIN
1. THE LADY FERNS
Fronds one to three feet high, broadly lanceolate, or ovate-oblong, tapering towards the apex, bipinnate. Pinnae lanceolate, numerous. Pinnules oblong-lanceolate, cut-toothed or incised. Fruit-dots short, variously curved. Indusium delicate, often reniform, or shaped like a horseshoe, in some forms confluent at maturity.
Widely distributed, common and varying greatly in outline. The newer nomenclature separates the lady fern of our section into two distinct species, which should be carefully studied.[A]
[Footnote A: See monograph by F.K. Butters in Rhodora of September, 1917.]
(1) THE UPLAND LADY FERN. ATHYRIUM ANGUSTUM
The rootstock or rhizome of the Upland Lady Fern here pictured shows how the thick, fleshy bases of the old fronds conceal the rootstock itself. In the Lowland Lady Fern the rootstock is but slightly concealed by old stipe bases, and so may be distinguished from its sister fern.
One design of such rootstocks is to store up food (mostly starch), during the summer to nourish the young plants as they shoot forth the next spring. The undecayed bases of the old stipes are also packed with starch for the same purpose.
Rootstocks horizontal, quite concealed by the thick, fleshy bases of old fronds. Scales of the long, tufted stipes dark brown. Indusium curved, often horseshoe-shaped, usually toothed or fringed with fine hairs, but without glands. Fronds bipinnate, one to three feet high, widest near the middle.
This is the common species of northern New England and the Canadian Provinces. The fronds differ very widely in form and a great many varieties have been pointed out, but the fern student, having first learned to identify the species, will gradually master the few leading varieties as he meets them.
Those growing in warm, sunny places where the fruit-dots when mature incline to cover the whole back of the frond are called "sun forms." These are varieties TYPICUM and ELATIUS, both with the pinnae obliquely ascending (including variety angustum of D.C. Eaton), but the latter has broader fronds with the pinnules of the sterile fronds oblong-lanceolate, somewhat acute and strongly toothed or pinnatifid.
Var. RUBELLUM has the sori distinct even when mature; its pinnules stand at a wide angle from the rachis of the pinna and are strongly toothed or pinnatifid with obtuse teeth. This variety favors regions with cool summers, or dense shade in warmer regions. The term RUBELLUM alludes to the reddish stems so often seen but this sign alone may not determine the variety. It occurs throughout the range of the species, being a common New England fern. Fernald remarks that this is also a common form of the species in southern Nova Scotia.
Among other varieties named by Butters are CONFERTUM, having the pinnules irregularly lobed and toothed; joined by a membranous wing, the lobes of the pinnules broad and overlapping, giving the fern a compact appearance; LACINIATUM with pinnules very irregular in size and shape, with many long, acute teeth, which project in various directions. "An abnormal form which looks as if it had been nibbled when young."
These varieties are represented in the Gray Herbarium.
(2) THE LOWLAND LADY FERN
Rootstocks creeping, not densely covered with the persistent bases of the fronds. Stipes about as long as the blade. Scales of the stipe very few, seldom persistent, rarely over 3-16 of an inch long. Fronds narrowly deltoid, lanceolate, widest near the base, the second pair of pinnae commonly longest. Indusia ciliate, the cilia (hairs) ending in glands. Spores dark, netted or wrinkled.
The following two forms are named by Butters:
F. TYPICUM. The usual form frequent in eastern Massachusetts, Rhode Island, Connecticut, New York, Pennsylvania, North Carolina, Ohio, and Missouri.
F. SUBTRIPINNATUM. An unusually large and rare form with triangular, lanceolate, and pinnatifid pinnules, having blunt, oblong segments. Wet situations in half shade. Massachusetts, West Virginia, and Virginia.
Our lowland or southern lady fern flourishes in the southern states, comes up the Atlantic Coast until it meets the upland or northern species in Pennsylvania and southern New England, and their identification can hardly fail to awaken in the student a keen interest.
Our American botanists are inclined to think that the real Athyrium filix-femina is not to be found in the northeastern United States, but is rather a western species, with its habitat in California and the Rocky Mountain region and identical with Athyrium cyclosorum.
But whatever changes may occur in the scientific name of the old Athyrium filix-femina, the name lady fern will not change, but everywhere within our limits it will hold its own as a familiar term.
Underwood, writing of the lady fern under the genus Asplenium, mentions the form "exile, small, starved specimens growing in very dry situations and often fruiting when only a few inches high." He also mentions Eaton's "angustum," and alludes to the "Remaining sixty-three varieties equally unimportant that have been described of this species."
The lady fern is common in moist woods, by walls and roadsides, and at its best is a truly handsome species, although, like Mrs. Parsons, we have noticed that in the late summer it loses much of its delicacy. "Many of its forms become disfigured and present a rather blotched and coarse appearance." The lady fern has inspired several poems, which have been quoted more or less fully in the fern books. The following lines are from the pen of Calder Campbell:
"But not by burne in wood or dale Grows anything so fair As the palmy crest of emerald pale Of the lady fern when the sunbeams turn To gold her delicate hair."
Referring, perhaps, to the fair colors of the unfolding crosiers revealing stipes of a clear wine color in striking contrast with the delicate green of the foliage.
In identifying this fern the novice should bear in mind the tendency of the curved sori of youth to become straightened and even confluent with age, although such changes are rather unreliable. Possibly the suggestion of the poetic Davenport may be helpful to some that there is "An indefinable charm about the various forms of the lady fern, which soon enables one to know it from its peculiarly graceful motion by merely gently swaying a frond in the hand." Spores ripen in August.
The lady fern is very easy to cultivate and when once established is apt to crowd aside its neighbors.
(3) SILVERY SPLEENWORT. ATHYRIUM ACROSTICHOIDES
Asplenium acrostichoides. Asplenium thelypteroides
Fronds two to four feet tall, pinnate, tapering both ways from the middle. Pinnae deeply pinnatifid, linear-lanceolate, acuminate. Lobes oblong, obtuse, minutely toothed, each bearing two rows of oblong or linear fruit-dots. Indusium silvery when young.
The sterile fronds come up first and the taller, fertile ones do not appear until late in June. Where there are no fruit-dots the hairs on the upper surface of the fronds will help to distinguish it from specimens of the Marsh fern tribe, which it somewhat resembles. The regular rows of nearly straight, clear-cut sori of the fertile fronds are very attractive, and the lower ones, as well as those at the slender tips of the pinnae, are frequently double.
Rich woods and moist, shady banks, New England to Kentucky and westward. Generally distributed but hardly common.
(4) NARROW-LEAVED SPLEENWORT
ATHYRIUM ANGUSTIFOLIUM. Asplenium angustifolium
Fronds one to four feet tall, pinnate. Pinnae numerous, thin, short-stalked, linear-lanceolate, acuminate, those of the fertile fronds narrower. Fruit-dots linear. Indusium slightly convex.
In rich woods from southern Canada and New Hampshire to Minnesota and southward. September. Not common. Mt. Toby, Mass., Berlin and Meriden, Conn., and Danville, Vt. Can be cultivated but should not be exposed to severe weather, as its thin and delicate fronds are easily injured. Woolson writes of it, "There is nothing in the fern kingdom which looks so cool and refreshing on a hot day as a mass of this clear-cut, delicately made-up fern."
Sori linear, a row on either side of the midvein, and at right angles to it, the indusium appearing to be double. (Scolopendrium is the Greek for centipede, whose feet the sori were thought to resemble. Phyllitis is the ancient Greek name for a fern.) Only one species in the United States.
(1) Scolopendrium vulgare
Fronds thick and leathery, oblong-lanceolate from an auricled, heart-shaped base, ten to twenty inches long and one to two inches wide. Margin entire, bright green.
In shaded ravines under limestone cliffs. Chittenango Falls, and Scolopendrium Lake, central New York, and Tennessee. Also, locally in Ontario and New Brunswick. One of the rarest of our native ferns, although very common in Great Britain. This plant is said to be easily cultivated, and to produce numerous varieties. According to Woolson, "No rockery is complete without the Hart's Tongue, the long, glossy, undulating fronds of which are sufficiently unique to distinguish any collection." In cultivation it "needs light protection through the winter in northern New England."
WALKING FERN. WALKING LEAF
Fruit-dots oblong or linear as in Asplenium, but irregularly scattered on either side of the reticulated veins of the simple frond, the outer ones sometimes confluent at their ends, forming crooked lines (hence, the name from the Greek meaning crooked sori). Only one species within our limits.
Fronds evergreen, leathery, four to eighteen inches long, heart-shaped at the base, but tapering towards the apex, which often roots and forms a new plant. Veins reticulated. The auricles of this species are sometimes elongated and may even take root.
This curious and interesting fern is one of the finest for rockeries, the tips taking root in rock-fissures. Shaded limestone, or sometimes other rocks. Shapleigh and Winthrop, Me., rarely in New Hampshire (Lebanon), and Connecticut, Mt. Toby, Mass., and western New England; also Canada to Georgia and westward.
THE SHIELD FERNS
THE CHRISTMAS AND HOLLY FERNS
These have been grouped with the wood ferns, but are now usually placed under the genus Polystichum, which has the sori round and covered with a circular indusium fixed to the frond by its depressed center. The wood ferns, on the other hand, have a kidney-shaped indusium attached to the fronds by the sinus. (Polystichum is the Greek for many rows, the sori of some species being in many ranks.)
(1) THE CHRISTMAS FERN
Polystichum acrostichoides. Aspidium acrostichoides
Stipes clothed with pale, brown scales. Frond rigid and evergreen, one to two feet long, lanceolate, pinnate. Pinnae linear-lanceolate, scythe-shaped, auricled on the upper side, and with bristly teeth; fertile pinnae contracted toward the top, bearing two rows of sori, which soon become confluent and cover the entire surface. Indusium orbicular, fixed by its depressed center.
F. incisum is a form in which the pinnae are much incised.
F. crispum has the edges of its pinnae crisped and ruffled. The name Christmas fern, due to John Robinson, of Salem, Mass., suggests its fitness for winter decoration. Its deep green and glossy fronds insure it a welcome at Christmas time. "Its mission is to cheer the winter months and enhance the beauty of the other ferns by contrast." In transplanting, a generous mass of earth should be included and its roots should not be disturbed.
(2) BRAUN'S HOLLY FERN
Polystichum Braunii. Aspidium aculeatum Braunii
Fronds thick, rigid, one to two feet long, spreading, lanceolate, tapering both ways, bipinnate. Pinnules ovate or oblong, truncate, nearly rectangular at the base, sharply toothed and covered beneath with chaff and hairs. Fruit-dots small and near the mid veins. Indusium orbicular, entire. Stipes chaffy with brown scales.
This handsome fern is rather common in northern New England. We have collected it in the Willoughby Lake region, Vt., and it is found at Mt. Mansfield, Randolph, and elsewhere in that state; also at Gorham, N.H., and Fernald reports it as common in northern Maine. It also grows in the mountains of New York and Pennsylvania, and westward. It was formerly thought to be a variety of the prickly shield fern (P. aculeatum), which has a very wide range and numerous varieties. The fronds remain green through the winter but the stipes weaken and fall over.
(3) HOLLY FERN. Polystichum Lonchitis
Fronds linear-lanceolate, short-stalked and rigid, eight to fifteen inches long. Pinnae broadly lanceolate-falcate or the lowest triangular, strongly auricled on the upper side, densely spinulose-toothed. Sori midway between the margin and midrib.
The name holly fern suggests its resemblance to holly leaves with their bristle-tipped teeth. The specific name lonchitis (like a spear) refers to its sharp teeth. A northern species growing in rocky woods from Labrador to Alaska, and south to Niagara Falls, Lake Superior and westward. Its southern limits nearly coincide with the northern limits of the Christmas fern.
THE MARSH FERN TRIBE
Under this designation Clute has grouped three of the shield ferns, which have a close family resemblance, and has thus distinguished them from the wood ferns, which also belong to the shield fern family.
(1) THE MARSH FERN
Aspidium thelypteris. THELYPTERIS PALUSTRIS Dryopteris thelypteris. Nephrodium thelypteris
These are all good names and each one is worthy to be chosen. Aspidium, Greek for shield, in use for a century, adopted in all the seven editions of Gray's Manual, is still the most familiar and pleasing term to its friends. Dryopteris, Greek for oak fern, has been chosen by Underwood and Britton and Brown and has grown in favor. Nephrodium, meaning kidney-like, favored by Davenport, Waters and, of late, Clute, is a most fitting name. THELYPTERIS, meaning lady fern, is found to be the earliest name in use and according to rule the correct one.
Fronds pinnate, lanceolate, slightly or not at all narrowed at the base. Pinnae horizontal or slightly recurved, linear-lanceolate and deeply pinnatifid. Lobes obtuse, but appear acute when their margins are reflexed over the sori. Veins once forked. Indusium minute. Stipes tall, lifting the blades ten to fifteen inches above the mud, whence they spring.
The fronds of the marsh fern are apt to be sterile in deep shade. It may be readily distinguished from the New York fern by its broad base, instead of tapering to very small pinnae; by its long stalk, lifting the blade up into the sunlight, and by the revolute margins of the fertile fronds, which have suggested for it the name of "snuff-box" fern. It is separated from the Massachusetts fern by its forked veins. Common in marshes and damp woodlands; Canada to Florida and westward. While the marsh fern loves moisture and shade it is sometimes found in dry, open fields. Miss Lilian A. Cole, of Union, Me., reports a colony as growing on land above the swale in which Twayblade and Adder's Tongue are found, "around rock heaps in open sunlight on clay soil, but homely and twisted," as if a former woodsy environment had been long since cleared away while the deserted ferns persisted.
(2) MASSACHUSETTS FERN
Aspidium simulatum. THELYPTERIS SIMULATA Dryopteris simulata. Nephrodium simulatum
Fronds pinnate, one to three feet long, oblong-lanceolate, somewhat narrowed at the base. Pinnae lanceolate, deeply pinnatifid, the lower most often turned inward. Veins simple. Indusium glandular. Sori rather large.
Resembles the marsh fern, of which it was once thought to be a variety. In some respects it is also like the New York fern, and is in fact intermediate between the two.
That it is a distinct species was first pointed out by Raynal Dodge in 1880, and it later was named simulatum by Geo. E. Davenport because of its similarity to a form of the lady fern. It may be identified by its thin texture and particularly by its simple veins. On account of its close resemblance to the marsh fern, Clute would call it "The lance-leaved Marsh Fern," instead of the irrelevant name of Massachusetts Fern. Woodland swamps usually in deep shade, New England to Maryland and westward. Often found growing with the marsh fern.
(3) NEW YORK FERN
Aspidium noveboracense. THELYPTERIS NOVEBORACENSIS Dryopteris noveboracensis. Nephrodium noveboracense
Fronds pinnate, tapering both ways from the middle. Pinnae lanceolate, pinnatifid, the lowest pairs gradually shorter and deflexed. Veins simple. Indusium minute and beset with glands.
Very common in woodlands, preferring a dryer soil than the marsh fern. August. The fronds are pale green, delicate and hairy beneath along the midrib and veins.
When bruised its resinous glands give out a pleasing, ferny odor. This species can be distinguished from every other by the greatly reduced pinnae at its base. Throughout North America east of the Mississippi.
THE BEECH FERNS
The beech ferns are often classed with the polypodies, because, like them, they have no indusium; but in other ways they are more akin to the wood ferns. Their stipes are not jointed to the root stock, nor are their sori at the ends of the veins as in the polypodies. We here place them with the wood ferns, retaining the familiar name Phegopteris but giving THELYPTERIS as a synonym. The fruit-dots are small, round and naked, borne on the back of the veins below the apex. Stipe continuous with the rootstock. Veins free. (The name Phegopteris in Greek means oak or beech fern.)
(1) OAK FERN
Phegopteris dryopteris. THELYPTERIS DRYOPTERIS
Fronds glabrous, broadly triangular, ternate, four to seven inches broad, the divisions widely spreading, each division pinnate at the base. Segments oblong, obtuse, entire or toothed. Fruit-dots near the margin. Rootstock slender and creeping from which fronds are produced all summer, in appearance like the small, ternate divisions of the bracken.
This dainty fern has fronds of a delicate yellow-green, "the greenest of all green things growing." Its ternate character is shown even in the uncoiling of the fronds, the three round balls suggesting the sign of the pawnbroker. The parts of the oak fern develop with great regularity, each pinna, pinnule and lobe having another exactly opposite to it nearly always. In rocky woods, common northward; also in Virginia, Kansas and Colorado. A fine species for cultivation at the base of the artificial rockery.
(2) THE NORTHERN OAK FERN
Phegopteris Robertiana. Phegopteris calcarea
Resembles the oak fern, but with fronds rather larger, especially the terminal segment; also more rigid and coarser in appearance. Stalks and fronds minutely glandular beneath. Lower pinnules of the lateral divisions scarcely longer than the others. Often called "Limestone Polypody," the beech ferns having formerly been classed with the polypodies. Britton and Brown designate it as the "Scented Oak Fern." Canada and the northwestern states. Rare.
(3) BROAD BEECH FERN
Fronds triangular, broader than long, seven to twelve inches broad, spreading more or less horizontally at the summit of the stipe; pubescent and often glandular beneath; pinnae fragrant, lanceolate, the lowest pair usually much larger than those above, having the segments elongated and cut into lobes. Basal segments decurrent and forming a many-angled wing along the main rachis. Fruit-dots small, near the margin.
The broad beech fern is usually larger than its sister, the long beech fern, and extends farther south, ranging from New England to Minnesota and southward to Florida. It is sometimes called "six-angled polypody." According to Dodge it is most common in Rhode Island and Connecticut. It prefers rather dry, open woods. It is said to have a pleasant, ferny odor when bruised. August.
(4) LONG BEECH FERN
Phegopteris polypodioides. THELYPTERIS PHEGOPTERIS
Fronds triangular, longer than broad, four to six inches long, twice pinnatifid. Pinnae lanceolate, acuminate, the lowest pair deflexed and standing forward; cut into oblong, obtuse segments. Fruit-dots near the margin.
Compared with the broad beech fern this is the more northern species. While usually quite distinct in structure, it sometimes approaches its sister fern rather closely.
It prefers deep woods and shaded banks. Newfoundland to Alaska and southward to the mountains of Virginia. July.
THE FRAGRANT FERN
Aspidium fragrans. Nephrodium fragrans
THELYPTERIS FRAGRANS. Dryopteris fragrans
Fronds four to twelve inches high, glandular-aromatic, narrowly lanceolate and twice pinnate or nearly so. Pinnae oblong-lanceolate, pinnate or deeply pinnatifid. Pinnules toothed or entire nearly covered beneath with the large, thin, imbricated indusia which are orbicular with a narrow sinus, having the margins ragged and sparingly glanduliferous. Stipe short and chaffy.
The fragrant fern grows on high cliffs among the mountains of northern New England. It is reported from scattered stations in northern Maine, from north of the White Mountains and from Sunapee Lake in New Hampshire, and in the Green Mountains south to central Vermont, New Brunswick and to Minnesota. Found also in Alaska and Greenland. This much-coveted fern has a singularly sweet and lasting fragrance, compared by some to strawberries, by others to new-mown hay and sweet brier leaves. We have seen herbarium specimens that were mildly and pleasantly odorous after several years. When growing the fern may be tested "by its fragrance, its stickiness and its beautiful brown curls." Evergreen. Spores ripen the middle of August.
KEY TO THE WOOD FERNS
Fronds pinnate, the pinnae pinnatifid; Blade soft and thin, not evergreen; Lower pinnae reduced to mere lobes New York Fern Lower pinnae but slightly reduced; Veins simple......................Massachusetts Fern Veins forked..............................Marsh Fern
Blade rather thick (subcoreaceous) mostly evergreen; Fronds small, narrow, glandular, rock species Fragrant Fern Fronds large, two or more feet high; Lower pinnae short, broadly triangular Crested Shield Fern Lower pinnae longer; Sori close to the margin.... Marginal Shield Fern Sori nearer the midvein; Frond lanceolate....................Male Fern Frond ovate..............Goldie's Shield Fern
Fronds twice pinnate with the lower pinnules pinnatifid Boott's Shield Fern
Fronds nearly thrice pinnate................Spinulose Shield Fern
THE WOOD FERNS
The ferns of this group, not counting the small fragrant fern, prefer the woods or at least shady places. Although the genus Polystichum represents the true shield ferns, the wood ferns are also thus designated, as their indusia have nearly the shape of small, roundish shields. The old generic name for them all was Aspidium (meaning shield), first published in 1800. For a long time its chief rival was Nephrodium (kidney-like), 1803. Many modern botanists have preferred the earlier name Dryopteris (1763), meaning oak fern, alluding, perhaps, to its forest-loving habits. THELYPTERIS, still earlier (1762), may supersede the others.
(1) MARGINAL SHIELD FERN, EVERGREEN WOOD FERN
Aspidium marginale. THELYPTERIS MARGINALIS Dryopteris marginalis. Nephrodium marginale
Fronds from a few inches to three feet long, ovate-oblong, somewhat leathery, smooth, twice pinnate. Pinnae lanceolate, acuminate, broadest just above the base. Pinnules oblong, often slightly falcate, entire or toothed. Fruit-dots large, round, close to the margin. Rocky hillsides in rich woods, rather common throughout our area. The heavy rootstock rises slightly above the ground and is clothed at the crown with shaggy, brown scales. Its rising caudex, often creeping for several inches over bare rocks, suggests the habit of a tree fern. In early spring it sends up a graceful circle of large, handsome, bluish-green blades. The stipes are short and densely chaffy. No other wood fern endures the winter so well. The fronds burdened with snow lop over among the withered leaves and continue green until the new ones shoot up in the spring. It is the most valuable of all the wood ferns for cultivation.
(2) THE MALE FERN
Aspidium Filix-mas. THELYPTERIS FILIX-MAS Dryopteris Filix-mas. Nephrodium Filix-mas
Fronds lanceolate, pinnate, one to three feet high growing in a crown from a shaggy rootstock. Pinnae lanceolate, tapering from base to apex. Pinnules oblong, obtuse, serrate at the apex, obscurely so at the sides, the basal incisely lobed, distant, the upper confluent. Fruit-dots large, nearer the mid vein than the margin, mostly on the lower half of each fertile segment.
The male fern resembles the marginal shield fern in outline, but the fronds are thinner, are not evergreen, and the sori are near the midvein. Its use in medicine is of long standing. Its rootstock produces the well-known filix-mas of the pharmacist. This has tonic and astringent properties, but is mainly prescribed as a vermifuge, which is one of the names given to it. In Europe it is regarded as the typical fern, being oftener mentioned and figured than any other. In rocky woods, Canada, Northfield, Vt., and northwest to the great lakes, also in many parts of the world.
(3) GOLDIE'S FERN
Aspidium Goldianum. THELYPTERIS GOLDIANA Dryopteris Goldiana. Nephrodium Goldianum
Fronds two to four feet high and often one foot broad, pinnate, broadly ovate, especially the sterile ones. Pinnae deeply pinnatifid, broadest in the middle. The divisions (eighteen or twenty pairs) oblong-linear, slightly toothed. Fruit-dots very near the midvein. Indusium large, orbicular, with a deep, narrow sinus. Scales dark brown to nearly black with a peculiar silky lustre.
A magnificent species, the tallest and largest of the wood ferns. It delights in rich woodlands where there is limestone. Its range is from Canada to Kentucky. While not common, there are numerous colonies in New England. It is reported from Fairfield, Me., Spencer and Mt. Toby, Mass., and frequently west of the Connecticut River. We have often admired a large and beautiful colony of it on the west side of Willoughby Mountain in Vermont. It is easily cultivated and adds grace and dignity to a fern garden.
(4) THE CRESTED FERN
Aspidium cristatum. THELYPTERIS CRISTATA
Dryopteris cristata. Nephrodium cristatum
Fronds one to two feet long, linear-oblong or lanceolate, pinnate, acute. Pinnae two to three inches long, broadest at the base, triangular-oblong, or the lowest triangular. Divisions oblong, obtuse, finely serrate or cut-toothed, those nearest the rachis sometimes separate. Fruit-dots large, round, half way between the midvein and the margin. Indusium smooth, naked, with a shallow sinus.
The short sterile fronds, though spreading out gracefully, are conspicuous only in winter; while the fertile fronds, tall, narrow and erect, are found only in summer.
It is one of our handsomest evergreen ferns and even the large sori, with their dark spore cases and white indusia, are very attractive. The fertile pinnae have a way of turning their faces upward toward the apex of the frond for more light. In moist land, Canada to Kentucky.
Var. Clintonianum. Clinton's Wood Fern. Resembles the type, but is in every way larger. Divisions eight to sixteen pairs. Fruit-dots near the midvein, the sides of the sinus often overlapping. South central Maine to New York and westward. "Rare in New England attaining its best development in western sections." (Dodge.) Mt. Toby, Mass., Hanover, N.H. July. Fine for cultivation.
CRESTED MARGINAL FERN
Aspidium cristatum X marginale
Both the crested fern and Clinton's fern appear to hybridize with the marginal shield fern with the result that the upper part of the frond is like marginale and the lower like cristatum, including the veining and texture.
This form was discovered by Raynal Dodge, verified by Margaret Slosson and described by Geo. E. Davenport, who had a small colony under cultivation in his fern garden at Medford, Mass., and to him the writer and other friends are indebted for specimens.
Found occasionally throughout New England and New Jersey. Other supposed hybrids have been found between the marginal shield and the spinulose fern and its variety intermedium, and with Goldie's fern; also between the crested fern, including Clinton's variety and each of the others mentioned; and, in fact, between almost all pairs of species of the wood ferns, although we do not think they have been positively verified. Still other species of ferns are known to hybridize more or less, as we saw in the case of Scott's spleenwort.
(5) BOOTT'S SHIELD FERN
Aspidium Boottii. THELYPTERIS BOOTTII
Dryopteris Boottii. Nephrodium Boottii
Fronds one to three feet high, oblong-lanceolate, bipinnate, the upper pinnae lanceolate, the lower triangular with spinulose teeth. Sori in rows each side of the midvein, one to each tooth and often scattering on the lower pinules. Indusium large, minutely glandular, variable.
This fern has been thought to be a hybrid between the crested and spinulose ferns, but is now regarded as distinct. Like the crested fern its fertile fronds wither in autumn, while its sterile blades remain green throughout the winter. It differs from it, however, by being twice pinnate below, and from the typical spinulose fern by its glandular indusium; but from the intermediate variety it is more difficult to separate it, as that also has indusiate glands. The collector needs to study authentic specimens and have in mind the type, with its rather long, narrow blade as an aid to the verbal description, and even then he will often find it an interesting puzzle. Shaded swamps throughout our area.
(6) SPINULOSE SHIELD FERN
_Aspidium spinulosum. THELYPTERIS SPINULOSA
Dryopteris spinulosa. Nephrodium spinulosum_
Stipes with a few pale brown deciduous scales. Fronds one to two and one-half feet long, ovate-lanceolate, twice pinnate. Pinnae oblique to the rachis, the lower ones broadly triangular, the upper ones elongated. Pinnules on the inferior side of the pinnae often elongated, especially the lower pair, the pinnule nearest the rachis being usually the longest, at least in the lowest pinnae. Pinnules variously cut into spinulose-toothed segments. Indusium smooth, without marginal glands.
The common European type, but in this country far less common than its varieties. They all prefer rich, damp woods, and because of their graceful outline and spiny-toothed lobes are very attractive. They can be transplanted without great difficulty, and the fern garden depends upon them for its most effective lacework.
Var. intermedium has the scales of the stipe brown with darker center. Fronds ovate-oblong, often tripinnate. Pinnae spreading, oblong-lanceolate. Pinnules pinnately cleft, the oblong lobes spinulose-toothed at the apex. Margin of the indusium denticulate and beset with minute, stalked glands. In woods nearly everywhere—our most common form. Millions of fronds of this variety are gathered in our northern woods, placed in cold storage and sent to florists to be used in decorations.[A] As long as the roots are not disturbed the crop is renewed from year to year, and no great harm seems to result. Canada to Kentucky and westward.
[Footnote A: Horticulture reports that twenty-eight million fern leaves have been shipped from Bennington, Vt., in a single season; and that nearly $100,000 were paid out in wages.]
A tripinnate form of this variety discovered at Concord, Mass., by Henry Purdie, has been named var. CONCORDIANUM. It has small, elliptical, denticulate pinnules and a glandular-pubescent indusium.
Var. AMERICANUM (=dilatatum, syn.). Fronds broader, ovate or triangular-ovate in outline. A more highly developed form of the typical plant, the lower pinnae being often very broad, and the fronds tripinnate. Inferior pinnules on the lower pair of pinnae conspicuously elongated. A variety preferring upland woods; northern New England, Greenland to the mountains of North Carolina, Pennsylvania, Michigan and northward.
THE BLADDER FERNS. Cystopteris
"Mark ye the ferns that clothe these dripping rocks, Their hair-like stalks, though trembling 'neath the shock Of falling spraydrops, rooted firmly there."
The bladder ferns are a dainty, rock-loving family partial to a limestone soil. (The Greek name cystopteris means bladder fern, so called in allusion to the hood-shaped indusium.)
(1) THE BULBLET BLADDER FERN
Cystopteris bulbifera. Filix bulbifera
Fronds lanceolate, elongated, one to three feet long, twice pinnate. Pinnae lanceolate-oblong, pointed, horizontal, the lowest pair longest. Rachis and pinnae often bearing bulblets beneath. Pinnules toothed or deeply lobed. Indusium short, truncate on the free side. Stipe short.
One of the most graceful and attractive of our native ferns; an object of beauty, whether standing alone or massed with other growths. It is very easily cultivated and one of the best for draping. "We may drape our homes by the yard," says Woolson, "with the most graceful and filmy of our common ferns, the bladder fern." This fern and the maidenhair were introduced into Europe in 1628 by John Tradescant, the first from America.
It delights in shaded ravines and dripping hillsides in limestone districts. While producing spores freely it seems to propagate its species mainly by bulblets, which, falling into a moist soil, at once send out a pair of growing roots, while a tiny frond starts to uncoil from the heart of the bulb. Mt. Toby, Mass., Willoughby Mountain, Vt., calcareous regions in Maine, and west of the Connecticut River, Newfoundland to Manitoba, Wisconsin and Iowa; south to northern Georgia, Alabama and Arkansas.
(2) THE COMMON BLADDER FERN
Cystopteris fragilis. Filix fragilis
Stipe long and brittle. Fronds oblong-lanceolate, five to twelve inches long, twice pinnate, the pinnae often pinnatifid or cut-toothed, ovate-lanceolate, decurrent on the winged rachis. Indusium appearing acute at the free end. Very variable in the cutting of the pinnules.