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9 
wilting or curling ensues. When the wilting comes from 
this cause and the evaporation is checked at night, the 
leaves unroll and the plant shows its normal vigor. The 
effect of this concentration or drawing off of the plant juices 
seems beneficial in forwarding crop. Ihaveobserved during 
many years, that in seasons when the corn curled at day- 
time, but uncurled at night, such were seasons of large 
yields; but when the curling came from the true lack of 
water, as evidenced by the plant not unrolling at night, 
then a serious injury to crop was the result. We thus seem 
to be able to discriminate between two kinds of wilting: one 
coming from the absence of sufficient water inthe ground, 
a disadvantage to the plant; the other coming from the 
physiological action of plant growth whereby transpiration 
becomes in excess of the ability of the roots to supply, and 
which seems favorable to crop yield. 
Karly planting is usually recommended, but the rationale 
seems little understood. it is a matter of observation that 
there are conditions often apparent between crops of early 
and late planted seed. It is also a simple matter of demon- 
stration that during the spring season the soil is in general 
warmer than the air, while in-a later season these condi- 
tions are not as pronounced. During a warm spell in the 
spring the soil becomes well warmed, a cool spell follows, 
and then we have as contrasted conditions, a warm soil 
and a cool air. We may now ask ourselves as to the influ- 
ence these conditions have upon the plant. We know that 
in the greenhouse, the gardener who desires thrifty plants 
often encourages the root growth through bottom heat and 
_a cool air, and after the plant has thus become well estab- 
lished increases the air temperature and thus gets rapid and 
healthy growth. In spring nature furthers this process for 
us. The corn plant may serve as an illustration. During 
a cool spell after it is seen above the ground, the farmer 
may note very little progress in its growth, because the 
farmer only looks at externals; but were he to examine 
the rooting habit of the plant he would find that this ap- 
parently stationary plant is extending its roots rapidly in a 
warmer soil, so that when a warm season follows this 
apparent resting spell, the plant is already furnished with 
an abundance of roots, and responds ina rapid growth. It 
seems, from such data as we possess, that we are safe in 
saying that the variable weather of the spring season, 
whereby there are alternations of periods wherein the goil 
is warmer than the air, and the air warmer than the soil, 
is very favorable toward that healthy and well-balanced 
growth of the plant which, in the presence of fertility, may 
be expected to result in abundant crop. A very superficial 
examination of our temperature records will indicate the 
