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165 
YS THE SEASON OF MATURITY OF DIFFERENT VARIETIES OF THE 
SAME PLANT GOVERNED AT ALL BY THE DEPTH OF 
THE ROOTS 2 
The question arose whether one cause of early maturity 
in certain varieties may not be due to the roots taking their 
nourishment in shallower, and hence warmer, soil than 
later varieties. Several observations failed to confirm such 
an hypothesis. In the beet and radish, an early variety 
appeared to root shallower than a later one. In the carrot 
the difference was less marked. In the lettuce and pea, no 
difference was observed, while in corn, the later varieties 
rooted decidedly shallower than the earlier ones. 
‘THE INFLUENCE OF ROOT PRUNING ON ROOT GROWTH. 
Market gardeners find transplanting young plants of 
cabbage, tomato, etc., while growing in the cold frame, to 
be of great advantage in assisting them to endure the final 
‘removal to the open ground. The question arose as to the 
cause of the benefit thus ascribed to a _ process that 
would appear to be in itself detrimental. 
An experiment made during the spring with cabbage and 
tomato plants indicated that the benefit chiefly arises from 
the longer roots being broken in transplanting, which 
causes a compact growth of fibres near the base of the 
plant. This mat of fine roots carries the inclosed_ soil with 
it in the final transplanting, and thus many of the feeding 
parts are in a condition to commence absorption at once in. 
their new home. The experiments showed that precisely 
the same result may be secured by sowing the seeds thinly 
in the frame, and then severely root pruning the young 
plants from time to time, taking care to preserve favorable 
conditions for growth. 
Whether this checking of the root growth by transplant- 
ing, or root pruning, is, in itself, beneficial or otherwise, 
in its after effects upon the growth of the plant, 1s a ques- 
tion which I endeavored to settle by experiment, but upon 
which the results were only partially satisfactory. In ex- 
periments with young plants of cabbage and corn, root 
pruning seemed to increase the proportionate development 
of the root as compared to that of the top, but on the whole, 
to retard growth. In two experiments made in the open 
ground with corn plants, one indicated that any interfer- 
ence with the roots may be prejudicial to the growth of the 
plant, while the other showed a slight increase in growth 
following a single moderate root pruning, but a decided 
retardation following a second cutting of the roots. In 
every case, where the root pruning was performed in dry 
