30 MASS. EXPERIMENT STATION BULLETIN 382 



(25 mg./l., 6 hr.) followed by treatment with a dust containing indole- 

 butyric acid or naphthaleneacetic acid, but no benefit from the solution 

 treatment alone. Best rooting was of cuttings farthest from the terminal, 

 cuttings taken from lateral branches of lateral branches in the lower part 

 of the tree. 



Rooting of cuttings from very young trees, better in sand-peat than in 

 sand, was improved by treatment with indoleacetic acid (200 mg./l., 24 

 hr.) (109). 



Deuber got about 50 percent rooting of cuttings of lace-bark pine from 

 a tree ten years old and he mentions the rooting of cuttings of Scots pine, 

 Austrian pine, and a few other species by other investigators. In the 

 present limited state of our knowledge, propagators working with these 

 and other pines will probably do well to take cuttings, laterals not termi- 

 nals, from the lower part of the trees in late winter. Cuttings of lace- 

 bark pine, a variety of mountain pine (61), and white pine have sometimes 

 rooted better after treatment with indolebutyric acid; and this chemical, 

 if used, should probably be applied to dormant cuttings in a relatively 

 concentrated solution for a relatively short time. 



Poncirus trifoliata. Cuttings which were taken here in mid-December and 

 inserted in sand-peat rooted 60 percent in 9 weeks after treatment with 

 naphthaleneacetic acid (100 mg./l., 17 hr.). Untreated cuttings and those 

 similarly treated with indolebutyric acid were alive but not rooted at the 

 end of that time. 



Populus, poplar. Hardwood, April, cuttings of white poplar and black 

 poplar rooted poorly without treatment, very well after treatment with 

 indoleacetic acid (50 mg./L, 30 hr. or 100 mg./l., 18 hr.) (65). Rooting 

 of October cuttings of quaking aspen and March cuttings of large-toothed 

 aspen was much improved by treatment, the former with indoleacetic acid 

 (100 mg./L, 24 hr.) (109), the latter with indolebutyric acid (10 mg./l., 

 27 hr.) (91). Late November cuttings of cottonwood, untreated, rooted 

 well when buried in a cold pit for about two months before' being planted 

 (52). Treated hardwood cuttings of quaking aspen rooted better in sand 

 than in sand-peat (91). Rooting of softwood, July or early August, 

 cuttings of white poplar and of a hybrid was much improved by treatment; 

 indoleacetic acid (50 mg./L, 24 hr.) being effective with the former (65) 

 and indolebutyric acid (20 mg./L, 12 hr.) with the latter (1). 



Potentilla fruticosa is easily propagated by softwood cuttings. Taken here 

 in early July, they rooted 100 percent in sand in 3 weeks whether or not 

 they were treated. 



Prunus spp. The best time to take softwood cuttings is, generally speaking, 

 in late spring and early summer. Treated cuttings of three plums and a 

 cherry rooted best if taken immediately after growth had stopped (81); 

 similar cuttings of another cherry, if made of tips of shoots taken shortly 

 before they became woody (11). Indolebutyric acid (15 or 20 mg./L, 

 24 hr.) markedly improved the rooting of such cuttings of both plum and 

 cherry (81). Cuttings of a species of Prunus taken in mid-July rooted 90 

 percent in 38 days after treatment with naphthylacetamide (1:1000, in 

 powder), 5 percent without treatment (104). A few other species are 

 discussed separately below. 



Prunus ceo'asifera, cherry plum. Softwood cuttings, made in spring of 

 terminal shoots which were still growing, rooted 100 percent in 4 weeks 



