45 
It seems curious at first sight that an unusually large yield of 
seed should follow the ravages of the clover leaf-weevil. Yet this has 
occurred in several instances. Webster observed the fact in Ohio. The 
explanation is simple, however, in my opinion, for the weevil, when a 
pest, consumes enough leaf tissue to delay the growth of the plant 
materially, taking th? seed crop out of the reach of its worst insect 
enemies. The result is the same as that obtained by the seed growers 
who pasture the clover in May or early June. 
Early pasturing or cutting is the secret of a good seed crop, as the 
growers in New York, Ohio, Michigan, Canada, and elsewhere have 
found. The reason for the practice is not universally known, however, 
as is evident from the inadequate explanations that have appeared now 
and then in agricuHural publications. For example, Shaw says (Clo- 
vers, etc., p. 103), "Experience has shown, further, that, as a rule, bet- 
ter crops of clover seed may be obtained from clover that has been 
pastured off than from that which has been mown for hay, although to 
this rule there are some exceptions. This arises, in part, from the 
fact that the energies of the plant have been less drawn upon in pro- 
ducing growth, and, therefore, can produce superior seed heads and 
seed, and in part from the further fact that there is usually more 
moisture in the soil at the season when the plants which have been 
pastured off are growing. There would seem to be some relation be- 
tween the growing of good crops of clover seed and pasturing the 
same with sheep." The fact is that pasturing gives a good seed crop 
for the reason that it delays the heading of the plant until a time when 
the seed-midges and seed-chalcids are no longer on the wing and laying 
eggs. When precautions are not taken against these pests, they can be 
counted upon every year to destroy most of the clover seed. In this 
region the midge and the chalcid eat from 50 to 75 percent of the red- 
clover seed every year without hindrance. The farmer gets only 
what the insects leave. If he gets two bushels of seed to the acre, the 
insects have already eaten from two to six bushels off the same acre. 
Control of Clover Insects 
The insect pests of clovers are but seven, and they are within our 
control if we choose to control them. Moreover, they can be controlled 
by means that interfere little, if any, with usual farm practice; and the 
methods of control do not conflict with one another, but are essentially 
the same for all the clover pests, — referring especially to those of red 
clover. 
The worst of these to deal with, where it occurs injuriously, is the 
root-borer. If it is very destructive in spring, plow the clover under, 
for this insect has quite its own way. The other pests can be disposed 
of without sacrificing the plant. 
If the hay crop is threatened seriously in spring by the leaf-weevil 
or the clover-louse, pasture it or clip it back in May; otherwise, cut 
the hay as early as possible, in order to insure a good second growth. 
Usually, however, these two insects are subdued by natural agencies, 
in spite of their abundance. 
