Sept, i, 1921 
Growth in Branches of Young Pear Trees 
855 
tempt was made, however, to avoid all shoots which to any measure- 
able extent departed from the perpendicular. Further experimental 
work ought to be done to determine the ratio between the new mate¬ 
rial produced and the amount of shoot pruned off, as well as the ratio 
between the amount of new material produced and that left on the 
tree. 
At this point the question may logically be asked, “Does the severity 
of the pruning affect the total amount of wood produced in the follow¬ 
ing season ?” To answer the question we may consult the data given 
in Table III, which sets forth the mean total length of laterals produced 
on pruned and unpruned mother shoots. On the pruned trees the class 
range is three buds, on the unpruned it is eight buds. The larger range 
in the latter case is due to the smaller population and the necessity of 
avoiding classes of very low frequencies. 
Tabi*e III .—Total production of laterals on mother shoots possessing varying number 
of buds 
Mean number of buds on mother shoots. 
Treatment of mother shoots. 
Total 
mean 
lateral 
produc¬ 
tion. 
Root- 
incah- 
square 
devia¬ 
tion. 
K ..... .. 
Pruned 
Cm. 
246.3 
269.3 
240. 7 
245-9 
237-8 
237.2 
246. 1 
313 -1 
281. 6 
24. 22 
8......... 
Mean.. 
257.6 
TTnprnned 
142. 6 
134 - 1 
172.5 
16.47 
Mean... 
r 49 * 7 
It is easily seen from Table III that there is little real difference in 
the mean total length of laterals on mother shoots of different sizes. 
In both pruned and unpruned mother shoots it will be seen that, so far 
as total shoot growth is concerned, there is no marked or consistent 
difference between the various classes, though there is a tendency for 
greater growth output on the class of mother shoots possessing from 
25 to 27 buds. It will be found, however, that the values are not so 
widely dispersed from their respective means as to indicate deviations 
of marked biological significance. In each case the deviation of the 
