EXPERIMENTS WITH TREE SEEDS. 145 
and thumb, the radicle was removed or “ pinched back” to within 
a quarter of an inch of the seed, after which the acorns were 
planted. At three years old the plants were lifted, when it was 
found that, instead of having a single large tap-root, most of them 
were provided with two, three, or more (up to six) smaller roots 
(Fig. 5), and although these were still but poorly furnished with 
Fie. 5.—Plants produced from Acorns that had been allowed to germinate 
before sowing, and whose radicles had been pinched back. 
lateral rootlets, and persisted in going straight down into the 
soil, they cannot but be regarded as an improvement on the 
typical form of oak-root as seen in Figs, 1-4. 
As the accompanying Table shows, the treatment may possibly, 
in one set of experiments (the ‘‘B.” series), have had a slightly 
prejudicial effect on the germination and on the height-growth, 
though in the other series no such effect is visible. The root- 
VOL, XV. PART II. P 
