1210 



FERNS 



FERNS 



of the most graceful species of all is Cyathea 

 arborea, introduced into England from the West 

 Indies by Admiral Bligh in 1793. There are numer- 

 ous species almost equally fine, many of which are 

 not in general cultivation. The species with clean 

 trunks, from which the leaves are freely deciduous 

 after maturity, are the most pleasing; and among 

 those which deserve especial notice are the following: 

 Cyathea minor, a very slender Cuban plant with trunk 

 6 to 12 feet high and 1 to IJ2 inches thick, its several 

 slender bipinnate leaves borne in a spreading crown; 

 C. portoricensis, a tall Porto Rican species with large 

 nearly tripinnate leaves, its rachises dark, lustrous, 

 purplish brown; C. elegans, of Jamaica, a close ally of 

 ('. arborea, often attaining a wide spread of leaf at an 

 unusually early age; C. Werckleana, C. hemiotis, and C. 

 hastulata, of Costa Rica, a peculiar subgroup charac- 

 terized by having the leaves fuUy tripinnate, the ulti- 

 mate rachises diseontinuously alate ; C. divergens, extend- 

 ing in one form or another from the Andes to Costa 

 Rica, its huge fronds exceedingly lax and sometimes 

 even in large plants recurved nearly to the ground; C. 

 insignis of the Greater Antilles, in technical characters 

 allied to the well-known C. princeps of Mexico; C. 

 suprastrigosa and C. co?ispersa of Costa Rica and Pan- 

 ama, dehcate graceful tripinnatifid plants of the high 

 mountains; C. punctifera of Nicaragua and Costa Rica, 

 a plant of lower range, its huge tripinnatifid fronds 

 remarkably beautiful from the strong contrast afforded 

 by the slender rich brown rachises and the unusually 

 vivid green leaf-segments; C. aureonitens of Costa Rica 

 and Panama, a lofty plant with leaf-scars in distant zones, 

 having the unusual habit also of shedding piecemeal all 

 its large tripinnatifid fronds, seasonally. 



Of Alsophila, the two best-known species in cultiva- 

 tion are doubtless A. australis and A. aspera, the latter 

 a common West Indian plant. A. myosuroides, of Cuba, 

 Mexico, and Central America, has lately been reintro- 

 duced to cultivation. It is a remarkably handsome 

 plant, its rather harsh, heavy, gray-green, tripinnatifid 

 leaves borne from a copious mass of slender, glossy 

 brown scales. Another beautiful species, A. Satmnii, 

 from Mexico and Guatemala, has very large tripinnate 

 fronds, with woody castaneous rachises in striking 

 contrast. A favorite species in cultivation also is A. 

 guadripinnata {A. pruinala), native in the West Indies 

 and from Mexico to Chile, its short trunk bearing huge 

 four-pinnate fronds, bluish or silvery white beneath. 

 The genus Hemitelia includes not only plants of the 

 above sort, with tripinnatifid fronds (as, for example, 

 the well-known H. capensis), but also plants of a dis- 

 tinctly different type known as the subgenus Cnemi- 

 daria. These are H. horrida, of the West Indies, and 

 numerous related species of the American tropics, 

 many of which have long been cultivated in European 

 conservatories. They are characterized mainly by 

 short trunks and large, leafy, simply pinnate or bipin- 

 natifid fronds, and make a beautiful display in cultiva- 

 tion. Among them may be mentioned H. spcciosa, H. 

 betla, H. grandifolia, {H. insignis), H. spectabilis, and H. 

 subincisa. Their characters have recently been dis- 

 cussed at some length. (See Contr. U. S. Nat. Herb. 

 16:25-49, 1912.) 



Considering the wealth of material available in the 

 Americail tropics and the comparative ease with which 

 it may be secured, it is remarkable that so httle atten- 

 tion has been given to the introduction of recently 

 described species. The novelty and beauty of many of 

 these render an effort to this end exceedingly desirable 

 and advantageous from a horticultural point of view. 

 Costa Rica in particular has yielded many interesting 

 new species within late years. This region, which has 

 been called the richest in the world, will doubtless be 

 equaled by certain parts of the Andes of South 

 America, when that immense territory shall have been 

 adequately explored. William R. Maxon. 



Cultivation of tender ferns. 



To grow commercial varieties of ferns profitably, 

 the first care should be to secure the necessary number 

 of properly built and equipped houses, with a con- 

 veniently arranged workshop. The house which gives 

 the most general satisfaction runs north and south, has 

 an even-span roof, and with a fall to roof of 6 inches 

 to the foot. Its benches should be arranged to be about 

 7 feet wide, with a 24-inch path on either side. In an 

 18-foot house this will permit of having a 7-foot center- 

 table, two 3)-2-foot side benches and two 24-inch paths. 

 Benches should not be more than 3 feet above the 

 walks, as this will bring every part of the bench within 

 easy reach, and wUl permit of every plant being in 

 constant sight and easil}' cared for, which fact is 

 essential in the profitable cultivation of trade ferns. 



The width of house is immaterial, but when houses 

 adjoin, a width of 27 feet has been found to be very 

 satisfactory, as this permits the construction of three 

 7-foot benches, two 24-inch paths, and two paths 2}4 

 feet wide under each gutter. 



Thorough provision should be made for ventilation. 

 For a 27-foot house, a continuous row of ventilators of 

 at least 3 feet in width should be provided, with some 

 reliable apparatus for raising same. Heating is the 

 next important consideration. Either steam or hot 

 water will give equally good results if properly installed. 

 The safest way for the average grower is to give the 

 heating contract to some reliable firm. Water-taps 

 should be so arranged that a 25-foot hose attached to 

 same will easily reach any part of the house. A 25- 

 foot hose can easily be carried about without injuring 

 either itself or benches and plants; and iron pipe is of 

 only half the cost of good hose. In most fern-houses 

 drip is a source of great annoyance, and should be pre- 

 vented by the use of drip-bars, by having a drip-groove 

 plowed into the headers immediately under the ven- 

 tilating-sash, and also by having a groove in sides of 

 gutter-plates. This very shght additional expense will 

 very soon pay for itself by saving a great number of 

 plants, especially when growing very small ferns in 

 houses, such as have been transplanted from spore- 

 pots into boxes. Ventilators should fit into a groove 

 in ridge of house and be hinged to the ridge. When 

 ventilators are so arranged, air, which is very desirable 

 on a good many warm rainy days in the summer, can 

 be given without having plants in the houses suffering 

 from excessive moisture. Burning of the foliage will 

 also be avoided, as the plants will at no time be exposed 

 to the direct rays of the sun. Ventilators hinged on 

 header and opening on ridge will always give trouble. 

 No matter what kind of covering is put over the open- 

 ing, if it efficiently excludes the burning sun's rays it 

 will also prevent the ingress of air. 



A propagating-room should be provided; and in the 

 case of general trade ferns raised from spores, it is a 

 very safe rule to calculate on having from 60 to 70 

 square inches of room in the propagating-frame for 

 every 1,000 plants desired. The propagating-frame 

 should be 3' 2 feet wide, have sides 9 inches high, and, 

 to insure an even moisture, its bottom should be cov- 

 ered to the thickness of 1 inch with fine cinders with 

 the fine ashes removed, which make very clean and 

 efficient drainage material. The frame should be 

 covered with hght sash constructed with drip-bars, to 

 carry off condensation. 



Shading of fern-houses should have close attention. 

 It is best effected by the apphcation of a suitable wash 

 to the outside of glass on roof. The following composi- 

 tion for a wash has given excellent results for a number 

 of years: To two gallons of benzene or turpentine add 

 one pint (or more, according to time the shading is 

 desired to remain on houses) of linseed oil, five pounds 

 of pure white lead and enough whitening to inake 

 proper thickness (which can very easily be ascertained 



