280 



HORTICULTURE 



March 10, 1906 



Tree Ferns 



(See Frontispiece) 



Among ferns and other plants I think there is 

 nothing more imposing than a well-grown tree fern. 

 They are of hardy, some of very hardy constitution and 

 do not suffer from being shifted around. In summer, 

 for tropical effect in the shade, they are a sight and 

 yet with the exception of a few Balantium antarcticum 

 and Alsophila australis, there are hardly any to be seen 

 in commercial establishments. Young tree ferns are 

 also of great value for general use; they are good keep- 

 ers, quick growers, and when grown from spores are 

 Boon of salable size. 



Tree ferns are to ferns what trees are to shrubs ; they 

 have no woody trunk and do not grow in thickness in 

 the way that trees do. The trunk of most of the tree 

 ferns is produced by the agglomeration or overlapping 

 roots which grow around the spongy part of the center 

 of the fern from the base of the new fronds growing 

 from top to the bottom over those already there and 

 giving the trunk the thickness required to its height. 

 Those that grow more than one frond at a time make 

 more roots and have generally thicker trunks than those 

 that grow one frond after another. Those roots that 

 form the trunk are alive and have to be kept alive by 

 moisture, for the well growing of the plant. 



Tree ferns should be grown in relatively small pots 

 or tubs so as to keep them of a convenient size ; if plant- 

 ed in open ground in a conservatory some of them soon 

 grow too big, and reach the roof. Those from the 

 tropical regions, that grow very quickly, have that in- 

 convenience; when that happens they have to be cut 

 back about half their height, like a big cutting, in the 

 spring before they start their growth, and have to be 

 treated like newly imported trunks, but they become 

 soon re-established. The bottom part can be thrown 

 away. With a few exceptions they do not grow any 

 side shoots from the trunk. 



On both sides of the equator and in the Southern 

 Hemisphere tree ferns are found in all their beauty in 

 a wild state. In Australia and New Zealand are found 

 the most useful and hardy ones, with heavy trunks and 

 big crown of numerous fronds of very strong texture. 

 The trunks of these species, which are nearly all covered 

 with a thick layer of roots when imported, grow more 

 easily than those from the tropical region which are 

 of a different constitution, the trunk being of a drier 

 nature, with less root covering, and can not stand so 

 much traveling. They dry out quickly and the tops 

 being very soft, rot on the road and give much more 

 trouble to bring them to life again. 



It is certainly too tedious to raise them from young 

 plants to perfect ferns, therefore trunks are imported 

 and when shipped in the right time — that is, after their 

 last growth of the season, when they are ripe, dug out or 

 cut off the required length, the fronds cut off, and let 

 dry for a few days before they are packed without soil 

 in ventilated boxes in shavings — they generally arrive 



in good condition. As said before, those from the trop- 

 ical regions require more attention, and if sent in the 

 growing season their loss is nearly certain. 



To bring those imported trunks to life again, the best 

 way when they arrive is to put them under a bench in 

 a warm house on a layer of moss and keep them there 

 for a couple of weeks slightly moist, after which time 

 the root taps begin to work, and they can be potted, in 

 pots that allow of about three inches of soil space 

 between rim and trunk; the soil must be of fibrous 

 nature. After being potted, they have to be kept in a 

 warm shady place to start the growth, the trunk being 

 sprinkled three or four times a day. 



Like all other ferns, tree ferns are classified in genus 

 after the form of their fruit dots or indusium: 

 Alsophila, Cyathea, Dicksonia including Balantium 

 and Cibotium, Hemitelia. The ferns belonging to these 

 genera are not all tree ferns ; in Dicksonia, for instance, 

 there are many species which make no trunks or stems; 

 our Dicksonia (Dennstsedtia) punctilobula is an illus- 

 tration. 



There are about two hundred different tree ferns 

 known but very few of them are in cultivation. Here 

 are a few of the most common : 



Dicksonia (Balantium) antarctica is the most seen 

 and one of the nicest ; has a crown of fronds sometimes 

 as numerous as fifty together; the short-stalked fronds 

 are from three to six feet long, and about two broad, of 

 a very heavy texture, dark green on top and light 

 underneath; the stalks of the young fronds are covered 

 with long, narrow, brown scales; has a nice regular 

 thick trunk. It is one of the hardiest of the tree ferns, 

 often covered with snow in Australia, its native country. 



Dicksonia squarrosa from New Zealand has a flat 

 crown of numerous fronds of heavy texture and of a 

 dark, shining green color; the stalk is covered with 

 numerous black hairy scales. 



Dicksonia (Cyathea) Youngise from New South 

 Wales resembles much the preceding. The stalks are 

 covered with light brown scales. These two species, 

 which have slender trunks of a dry nature, have the 

 peculiarity of growing young plants on their surface. 



Cyathea dealbata from New Zealand is a very nice 

 and liardy tree fern. The fronds are about six feet 

 long and nearly white underneath with reddish spore 

 masses, which give them a distinct appearance. The 

 trunk is strong. 



Cyathea medularis from New Zealand is the biggest 

 growing of the cold tree ferns; the fronds, not very 

 numerous, are about ten feet long in developed plants; 

 the stalks are of jet black color, and in the young plants 

 they are covered with dark brown scales. It is a quick 

 grower and soon makes a big specimen. 



Cibotium Schiedei from Mexico has been lately ex- 

 tensively grown from seedlings in this country and some 

 good specimens can be seen. They seldom grow trunks 

 more than two feet high; the long drooping fronds, 

 which grow of big size, are of a light yellow green 

 color, glaucous underneath, of a very graceful effect ; 

 they are long-stalked and the stalks covered with 

 brownish hairy scales. 



Cibotium princeps (Cyathea insignia) from Cuba 

 and New Mexico is a very big-growing stove species; 



