J i8 



PLANT I'KOl'AGATION 



170. Evergreen mature wood cuttings, esi)ccially of cone-bearing 

 lilants (arbor vit;e, juniper and retinospora) are fall planted 

 under cover in sand either in a cool greenhouse or some other 

 cover. Usually they take root slowly, sometimes a full year (yew, 

 juniper), but continue green if properly shaded and watered. After 

 rooting they may remain in the flats till the following season for 

 out-of-door planting or may be potted. The cuttings, usually four 

 or five inches long, are always made of well-ripened wood some- 

 times two, three or even four years old. The needles or leaves are 

 cut from the lower two-thirds of the stem with a sharp knife. They 

 should never be pulled or rubbed off. Remaining leaves are not 

 covered with soil. Probably all cone-bearing trees may be prop- 

 agated by cuttings. It is not, however, prolitable to grow pine this 

 way; seed is cheaper. Spruce cuttings are very slow to root (12 

 to 18 months) so fine varieties are generally grafted. 



FIG. 105— CALLUSING BED FOR CUTTINGS AND ROOT GRAFTS 

 In t.his the bundles of grafts and cuttings are placed in fall or winter for spring 



planting. 



171. Eose cuttings of dormant wood are largely used both out 

 of doors and under glass. ^\ hen to be grown out of dnors the 

 cuttings are made about six inches long from mature wood in the 

 fall before severe freezing weather comes. Bundles are stored in 

 sand over winter and planted in spring in V-shaped trenches with 

 only one bud showing. Rich soil produces strong plants in one sea- 

 son. When grown under glass the cuttings are made in November 

 or December and planted in sand in cold frames or cool greenhouses. 

 By February or March they may be potted. W hen warm weather 

 arrives they are planted in rich soil. 



172. Ringing roses to facilitate cuttings propagation was done 

 experimentally by Greiner, a French investigator, who found that 

 such cuttings strike root much more readily than do ordinary ones. 

 The stems of the parent plants were ringed in July or August. By 

 November the wounds had callused. The method is recommended 

 for varieties diflncult to propagate by ordinary cuttings. Several 

 rings made at proper distances apart to get right-sized cuttings may 

 l)e made on the same branch, 



173. Cuttings from grafted grapes. — F. Baco, a French investiga- 

 tor, has proved that with certain varieties of grapes used as cions, 



