68 PRACTICAL PLANT PROPAGATION 



rolled out over the boxes when they need it, which is usually from 

 9 a.m. to 4 p.m. At other times of the day, however, and on cloudy 

 days the cuttings are better off for all the light possible. A safe 

 temperature is 50 degrees to 55 degrees." 



CHEMICAL TREATMENT TO HASTEN ROOTING 



In conducting some experiments along other lines, Prof. Otis 

 F. Curtis* found that certain chemicals actually hastened the root- 

 ing of Privet (Ligustrum ovalifolium) . This aroused his interest 

 and he tested the effect of various chemical treatments in this direc- 

 tion. He found that potassium permanganate was useful for hard- 

 wood cuttings because (1) the treatment causes a change in the 

 nature of the food supply of the twig; (2) it affects the rest period, 

 causing growth to start sooner than it normally would; (3) it upsets 

 the balance of food supply between tops and roots in favor of the 

 latter; (4) it retards the growth of micro-organisms; (5) it increases 

 respiration by hastening oxidation. It was found that treating the 

 cuttings for twenty-four hours with a 1 per cent solution of potas- 

 sium permanganate was beneficial. Fifty-two different treatments 

 were given the cuttings and all gave better results than where no 

 treatment was made, except when a too weak or a too strong 

 solution was used. 



In other experiments soft-wood cuttings of Tomatoes were 

 used, it was found that a sugar solution was beneficial. Placing 

 the cuttings in a 5 per cent solution of cane sugar for one or two days 

 proved best. The cuttings transform the sugar into starch and 

 rooting is hastened. When a sugar solution is used the terminal 

 bud does not develop, but buds lower down grow more readily. 

 The cane sugar treatment increases the danger of injury from bac- 

 terial decay, and this should be taken into consideration. 



FLORISTS' TIME TABLE FOR CUTTINGS 



Abutilon. Flowering Maple. Autumn. Soft wood. 55 to 65. 



Acacia. June or Winter. A. longifolia, A. heterophylla, A. puchella, 

 A. spiralis, A. platyptera, A, hispidissima and A. pubescens. Half- 

 ripe wood; not over \y% inches long. Take 6 weeks to 8 weeks to 

 root. Pot as soon as rooted as roots become brittle and are difficult 

 to transplant. 60 to 70. (See Darlington's Propagating Flat, 

 page 67. Also Erica, p. 69.) 



Acalypha. Autumn to Spring. 60 to 70. 



Agathaea (Felicia) (Blue Daisy). 55. Autumn and Spring. 



* Curtis, Otis F. Stimulation of Root Growth in Cuttings by Treatment with 

 Chemical Compounds. Memoir 14, Cornell University Agricultural Experiment 

 Station. 



