National Geographic : 1925 May
TH11E NATIONAL G;EOGRAPIHIC MAGAZINE Photograph from I. S. National Museum A BASKET WOVEN FROM A SIAM SE CLIMBING FERN The slight, twining stems of this species (Lygodiuni salicifolium), climbing Io feet high, are cut and dried in the sun, after which their outer part is split into long, fine strips. No dyes are used. ihe work of weaving a single small basket-like covered box such as this (illustration one-half natural size) requires three or four weeks. The art is dying out, being practiced mostly by prisoners nowadays. Next to Goldie's Fern (Dryopteris goldiana), the Marginal Fern is the most stately and at tractive of the common woodland ferns of east ern North America. It transplants easily and under suitable conditions responds well under cultivation. The thick fronds are thoroughly evergreen and, spreading outward, lie prostrate, like a green star, throughout the winter. The name alludes to the position of the sori, which are set close to the margins of the pinnules. CHRISTMAS FERN Polystichum acrostichoides (Michx.) Schott. Polypody Family [Plate XI] Excepting only the Common Wood-fern, the Christmas Fern is probably the best known of our eastern species. Its fronds are much sold by florists, under the name "Dagger Fern." Fortunately, it is abundant, growing usually in large colonies along the cool, shady banks of moist gullies and along steep, wooded roadsides, where in all seasons its glossy, rich green fronds are a familiar sight to passers-by. The uncoiling leaves of early spring are silvery green, from a superabundance of whitish scales that have protected the plant in winter. \hen full grown they are thick and thoroughly evergreen, well suited to the important part they play in Christmas decoration. The Christmas Fern has fronds of two sorts. The numerous sterile ones arch outward in a circle; the fertile ones-that is, those with contracted fertile tips - stand rigidly erect within, often to a height of three feet. Early in summer the circular parasol-like indusia are pushed aside and hidden by the ripening spo rangia, which spread over the under side of the fertile pinnme and thickly cover it with their brown remains. Although hardy, the Christmas Fern is none too tolerant of change in surroundings. To do best in cultivation, it should have deep soil in ample shade, and should be well watered. \Vith proper care, this is one of our most hand some ferns. SENSITIVE FERN Onoclea sensibilis L. Polypody Family [Plate XIlI] The Sensitive Fern is found in Europe, northern Asia, and eastern North America, and is known doubtfully in a fossil condition. It is a coarse, weedy-looking plant, as it grows in low thickets or in moist, open situations gener ally; but, as a counterfoil to the more delicate kinds, it is of distinct value in plantings of ferns, and, in its vivid yellowish-green coloring and sturdy growth, reveals an unsuspected charm of its own. Moreover, it is almost unique among our native ferns in its curious fertile fronds. These develop in late summer and present the greatest contrast to the leafy, sterile ones. The divisions are hard, of plump, berry-like form, and consist of tightly rolled lobes within which is borne a mass of sporangia. At maturity they burst open, to release the spores; but they retain their distended form, and the erect weather-beaten stalks surmounted by berry-like clusters stand upright to the following year. Through injury to the plant in the early growing season, numerous half-fertile fronds of curious shapes and sizes are sometimes produced later in the year. These have led to much dis cussion and are interesting objects of study, as showing the effort of the plant to transform into vegetative leaves, as they develop, buds that originally were destined to be fertile fronds of utterly different structure.