# How to Know the Ferns (7th ed)/Group I

FERN DESCRIPTIONS
"Nature made a fern for pure leaves."—Thoreau
GROUP I
STERILE AND FERTILE FRONDS TOTALLY UNLIKE; FERTILE FRONDS NOT LEAF-LIKE IN APPEARANCE
1. SENSITIVE FERN
Onoclea sensibilis
Newfoundland to Florida, in wet meadows.
Sterile fronds.—One or two inches to three feet high, broadly triangular, deeply cut into somewhat oblong, wavy-toothed divisions, the lower ones almost reaching the midrib, the upper ones less deeply cut; stalk long.
Fertile fronds.—Quite unlike the sterile fronds and shorter, erect, rigid, contracted; pinnules rolled up into dark-green, berry-like bodies which hold the spore-cases; appearing in June or July.
This is one of our commonest ferns, growing in masses along the roadside and in wet meadows. Perfectly formed sterile fronds are found of the tiniest dimensions. Again the plant holds its own among the largest and most effective ferns. From its creeping rootstock rise the scattered fronds ​Sensitive Fernwhich at times wear very light and delicate shades of green. There is nothing, however, specially fragile in the plant's appearance, and one is struck by the inappropriateness of its title. It is probable that this arose from its sensitiveness to early frosts.
Though one hesitates to differ from Dr. Eaton, who described the fertile fronds as "nearly black in color" and said that they were "not very common," and that a young botanist might "search in vain for them for a long time," my own experience has been that the fresh ones are ​very evidently green and neither scarce nor specially inconspicuous.
I have found these fertile fronds apparently full-grown in June, though usually they are assigned to a much later date. They remain standing, brown and dry, long after they have sown their spores, side by side with the fresh fronds of the following summer.
Detail a in Plate I represents the so-called var. obtusilobata. This is a form midway between the fruiting and the non-fruiting fronds. It may be looked for in situations where the fern has suffered some injury or deprivation.
2. OSTRICH FERN
Onoclea Struthiopteris
Nova Scotia to New Jersey, along streams and in moist woods. Growing in a crown, two to ten feet high.
Sterile fronds.—Broadly lance-shaped, once-pinnate; pinnæ divided into narrowly oblong segments which do not reach the midvein; stalk short, deeply channelled in front.
Fertile fronds.—Quite unlike the sterile fronds, growing in the centre of the crown formed by the sterile fronds, shorter, erect, rigid, with green, necklace-like pinnæ which hold the spore-cases; appearing in July.
PLATE I
SENSITIVE FERN a. Var. obtusilobata
This magnificent plant luxuriates especially in the low, rich soil which is subject to an annual overflow from our northern rivers. Its vase-like masses of foliage somewhat suggest the Cinnamon Fern, but the fertile fronds of the Ostrich Fern mature in July, some weeks later than those of its rival. They are dark-green, while those of the Cinnamon Fern are golden-brown. Should there be no fruiting fronds upon the plant, the Ostrich Fern can be distinguished by the free veins with simple veinlets (Plate II, a) of its pinnæ, the veins of the Cinnamon Fern being free and its veinlets forking (Pl. III, a), and by the absence of the tuft of rusty wool at the base of the pinnæ on the under side of the frond.
The Ostrich Fern does so well under cultivation that there is danger lest it crowd out its less aggressive neighbors. It propagates chiefly by means of underground runners. Mr. Robinson describes a specimen which he had planted in his out-door fernery that crawled under a tight board fence and reappeared in the garden of his neighbor, who was greatly astonished and equally delighted so unexpectedly to become the owner of the superb plant.
OSTRICH FERN
a Portion of sterile frond
b Fertile frond
c Detail, showing free veins with simple veinlets
3. CINNAMON FERN
Osmunda cinnamomea
Nova Scotia to Florida, in swampy places. Growing in a crown, one to five feet high.
Sterile fronds.— Broadly lance-shaped, once-pinnate; pinnæ cut into broadly oblong divisions that do not reach the midvein, each pinna with a tuft of rusty wool at its base beneath.
Fertile fronds.—Quite unlike the sterile fronds, growing in the centre of the crown formed by the sterile fronds and usually about the same height; erect, with cinnamon-colored spore-cases.
PLATE III
CINNAMON FERN
a Showing tuft of wool at base of pinna, also free veins with forking veinlets
The Cinnamon Fern is often confused with the Ostrich Fern. When either plant is in fruit there is no excuse for this mistake, as the cinnamon-colored spore-cases of the former appear in May, while the dark-green fertile fronds of the latter do not ripen till July. When the fruiting fronds are absent the forked veinlets (Plate III, a) of the Cinnamon Fern contrast with the simple veinlets of the other plant (Plate II, a). Then, too, the pinnæ of the Cinnamon Fern bear tufts of rusty wool at the base beneath, the remnants of the woolly garments worn by the young fronds.
The plant is a superb one when seen at its best. Its tall sterile fronds curve gracefully outward, while the slender fruit-clusters erect themselves in the centre of the rich crown. In unfavorable conditions, when growing in dry meadows, for instance, like all the Osmundas, and indeed like most growing things, it is quite a different plant. Its green fronds become stiff and stunted, losing all their graceful curves, and its fruit-clusters huddle among them as if anxious to keep out of sight.
Var. frondosa is an occasional form in which some of the fruiting fronds have green, leaf-like pinnæ below. These abnormal fronds are most abundant on land which has been burned over.
The Cinnamon Fern is a member of the group of Osmundas, or "flowering ferns," as they are sometimes called, not of course because they really flower, ​but because their fruiting fronds are somewhat flower-like in appearance. There are three species of Osmunda: the Cinnamon Fern, O. cinnamomea; the Royal Fern, O. regalis; and the Interrupted Fern, O. Claytoniana. All three are beautiful and striking plants, producing their spores in May or June, and conspicuous by reason of their luxuriant growth and flower-like fruit clusters.
The Osmundas are easily cultivated, and group themselves effectively in shaded corners of the garden. They need plenty of water, and thrive best in a mixture of swamp-muck and fine loam.
4. CURLY GRASS
Schizæa pusilla
Pine barrens of New Jersey.
Sterile fronds.—Hardly an inch long, linear, slender, flattened, curly.
Fertile fronds.—Taller than the sterile fronds (three or four inches in height), slender, with from four to six pairs of fruit-bearing pinnæ in September.
Save in the herbarium I have never seen this very local little plant, which is found in certain parts of New Jersey. Gray assigns it to "low grounds, pine barrens," while Dr. Eaton attributes it to the "drier parts of sphagnous swamps among white cedars."
In my lack of personal knowledge of Schizæa, I venture to quote from that excellent little quarterly, the Fern Bulletin, the following passage from an ​article by Mr. C. F. Saunders on Schizæa pusilla at home:
PLATE IV
OURLY GRASS