ON PROPAGATION BY CUTTINGS. 



251 



produced by watering every part of the house ; and it is so great that the 

 surface of the walls, of the stone shelves, and of the pots, is everywhere 

 covered with lichens, mosses, hepaticse (such as marchantia), and even 

 fungi. I'he warmth, it is needless to state, is produced by hot-water pipes 

 or flues, and by the sun ; and it is carried to a considerable degree further 

 than is ever done in growing plants for any other purpose than propagation. 

 In short, every plant in Mr. Cunningham's propagating-houses enjoys the 

 same close, still, moist, warm, unchanging atmosphere, which it would do if 

 placed under a bell-glass. The more rare plants which are to be propagated 

 are planted in a bed of sandy peat and leaf-mould, or of some such soil, 

 where they are found to grow much more freely than in pots, and speedily 

 to produce shoots, which are taken off in a young and tender state, and 

 struck in sand. Various modes are adopted to induce the plants which are 

 to be propagated from, to protrude young shoots, such as when they have 

 small leaves, like heaths, &c., by bending down, twisting them, &c. ; and 

 in the case of plants having larger leaves, such as the Statice arborea, or 

 some of the more rare fuchsias, by cutting a notch in the stem above every 

 bud, and inserting a wooden wedge in the notch to keep it open, in conse- 

 quence of which the ascending sap being checked, every bud protrudes a 

 shoot, which is taken off in a tender state, with or without the base of old 

 wood from which it sprang, according to circumstances. In some cases the 

 shoot is taken off, and the base left to produce other shoots from the latent 

 buds ; in other cases, the shoot and its base are taken off together, and occa- 

 sionally, before taking off the shoot and its base, a notch is made below the 

 bud as well as above it, and the lower notch as well as the upper one is kept 

 open by a wedge, till a callosity is formed on the upper edges of the lower 

 notch, from which roots are very readily protruded, after the cutting (with 

 its base attached) has been taken off and planted in sand. A stranger, in 

 passing through Mr. Cunningham's propagating-houses, is at first oppressed 

 with the excessive moisture of the atmosphere, and wonders that none of the 

 plants damp off ; but this seems to be prevented by the high temperature. 



575. Selecting the shoot. — The wood of the present or of the past year is 

 almost invariably chosen for cuttings. In the case of plants which are not 

 difficult to strike, a portion of the young shoot is cut off at any convenient 

 distance from the branch from which it proceeded, and of such a length as 

 may be considered most convenient for forming a plant. Thus in the case 

 of willows, gooseberries, currants, &c., from nine to eighteen inches is consi- 

 dered a suitable length ; and the points of the shoots of these and other 

 kinds of easily rooting plants are cut off, as not being sufficiently ripened 

 to have strong buds, or as containing too many small buds. In plants some- 

 what difficult to strike, lateral shoots are chosen, and these are often drawn 

 or " slipped " out of the wood, so as to carry with them the axillary forma- 

 tion of the bud and the vessels of the leaf. This is the only w^ay in which 

 shoots covered with a woolly tissue, such as several gnaphaliums and heli- 

 chrysums, can be made to root. This method is also very successful with 

 plants that are difficult to root, and that have leaves surrounded with 

 prickles, such as Mutism ilicifolia, Berkleya grandiflora, Logani« floribunda, 

 latifolia, &c.; also with those the leaves of which have stalks with very strong 

 veins, or their circumference is very strongly defined, stieh as Banksm grandis, 

 Berkleya ciliaris, the different species of Daviesia, Chorozema ovata, &c.; 

 or those that have whiged stems, such as Acacia alata. The reason of the 



