THE MULTIPLICATION OF PLANTS. 433 



there is above the cuttings the more evaporation there will be. It v^as for- 

 merly supposed that these cuttings must be started in the shade, as under a 

 northern roof. Most practical florists now strike them under southern or 

 other roofs with equal ease, taking care to break the force of the sun in the 

 middle of the day by lath screens or muslin. 



Hard cuttings, or cuttings of ripened wood, are those used for the propa- 

 gation of most small fruits. In general, hard cuttings are best when cut 

 in the fall, if properly stored. The first operation of independent growth 

 begins as soon as the cuttings are placed in moss or sand in the fall, and if 

 they do not freeze, it continues during the winter. This beginning of activ- 

 ity is the formation of a callus on the lower end of the cuttings. This 

 callus is a mass of cellular tissue which is deposited for the purpose of heal- 

 ing over the wounded surface. From this callus the roots start. If the 

 callus is well formed before cuttings are planted out in the spring, it 

 will represent a considerable gain in the growth, inasmuch as it must 

 form before roots can start. This same observation will apply to trees 

 which are transplanted in early fall, a practice always to be recommended, 

 unless severe climate or uncongenial soil forbid. In this rigorous climate it is 

 safer, also, to take cuttings in fall, to guard against winterkilling. Cuttings 

 of grapes, currants, quinces, etc., are taken in the fall, just before the 

 weather closes up, and are tied in bundles and placed in a cellar or pit. 

 They are commonly buried half their length in the sand. These cuttings 

 are from six to twelve inches long, the length commonly depending upon the 

 length of the internodes or spaces between the joints. They are planted iu 

 the spring by inserting them into the space made by a single thrust of a 

 spade. Usually the top bud is left above ground. As fast as the cuttings 

 are inserted, the earth is stamped firmly against them. Roots will usually 

 start from each subterranean bud. These hard cuttings are sometimes made 

 from wood two years and more old, but ordinarily they are taken from the 

 last growth. In most cases roots start more readily from this recently 

 ripened wood than from that of greater age. Grape cuttings can be taken 

 in November, at the time of pruning the vines, making them from the 

 larger canes of the season. Three buds are left on grape cuttings, usually. 



d. Of liootslochs — Rootstocks are underground stems. They can. be dis- 

 tinguished from true roots by the presence of joints, scales, and sometimes of 

 buds or eyes. Quackgrass and Canada thistles propagate themselves largely 

 by roots. A number of herbaceous ornamental plants are propagated by 

 cuttmgs from their rootstocks; also the common potato. 



c. Of Roots — Cuttings of true roots are not often made in ordinary 

 gardening. The most familiar example occurs in the case of the blackberry. 

 Here the roots are cut into sections two inches in length and the sections or 

 cuttings are planted horizontally in sand, being covered an inch or so deep. 



d. Of Leaves — Leaf cuttings are employed in propagating certain thick- 

 leaved, ornamental plants. The cabbage can be propagated in the same 

 manner. The leaf' is cut into triangular sections an inch or two long with 

 a portion of the midrib or a large vein coming at the point. This point is 

 inserted a half inch in sand, which is kept constantly moist. Sometimes 

 the leaf is not cut but is laid upon the sand and toothpicks stuck through the 

 larger veins at intervals to hold them to the soil. Roots form where there is 

 contact with the earth. 



6. Graftage. — Next to seedage, graf tage is undoubtedly the most important 



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