=2. Root Cuttings.=--Many plants can be multiplied with ease by means of short cuttings of the roots, particularly all species which posses a natural tendency to "sucker" or send up sprouts from the root. All root-stocks or underground stems can be made into cuttings. True root cuttings possess no buds whatever; the buds develop after the cutting is planted. Roots are cut into pieces from one to three inches long and are planted horizontally in soil or moss. These cuttings thrive best with bottom heat, but blackberries and some other plants, grow readily with ordinary out-door treatment. A root-cutting of the blackberry is shown in Fig. 46. (See Blackberry, in Chapter VI.) A growing dracæna cutting is exhibited in Fig. 47. The cuttings of this plant are handled in a propagating-frame or on a cutting bench in a warm greenhouse. The bouvardias and many other plants can be grown in the same manner. Many of the fruit-trees, as peach, cherry, apple and pear, can be grown readily from these short root-cuttings in a frame. Variegation cannot always be transmitted by root-cutting, _e. g._, _Symphytum asperrimum, variegatum_. Among kitchen garden plants, the horse-radish is the most familiar example of propagation by root-cuttings. The small side roots, a fourth inch or so in diameter, are removed when the horse-radish is dug in fall or spring, and are cut into four to six inch lengths, as seen in Fig. 48. These cuttings are known as "sets" among gardeners. (See Horse-radish, Chapter VI.) When the crowns of horse-radish are cut and used for propagation, the operation falls strictly under division, from the fact that buds or eyes are present; and the same remark applies to rhubarb, which, however, is not propagated by true root-cuttings. [Illustration: Fig. 48. Horse-radish root-cuttings.] =3. Stem Cuttings.=--Cuttings of the stem divide themselves into two general classes: those known as cutting of the ripe, mature or hard wood, and cuttings of the green, immature or soft wood. The two classes run into each other; no hard and fast lines can be drawn. _Hard-wood cuttings_ are made at any time from late summer to spring. It is advisable to make them in the fall in order to allow them to callus before the planting season, and to forestall injury which might result to the parent plant from a severe winter. They may be taken as early as August, or as soon as the wood is mature, and be stripped of leaves. Callusing can then take place in time to allow of fall planting. Or the cuttings taken in early fall may be planted immediately and be allowed to callus where they stand. All fall cutting beds should be mulched to prevent the heaving of the cuttings. As a rule, however, hard-wood cuttings are buried on a sandy knoll or are stored in moss, sand or sawdust in a cellar until spring. (See page 50.)