square foot. This grub-proofing has two effects: (a) it stops beetle
production from that lawn, and (b) it prevents the lawn grass being
damaged by the grubs of this and other annual grub species and by the
birds and animals, including moles, which damage grubby turf. For
grub-proofing I prefer to use chlordane. It may be applied in a spray,
at 8 ounces of 50% wettable powder to 1,000 square feet, or it may be
purchased in the more bulky 5% form and applied dry with a two-wheeled
lawn fertilizer spreader. For each 1,000 square feet I take 5 pounds of
5% chlordane and, since it tends to clog the spreader, I mix it in a
cardboard drum with 5 pounds of a dry, granular material such as the
activated-sludge fertilizer known as "Milorganite." The ten pounds of
mixture is then spread on the 1,000 square feet, half east and west,
half north and south.

If applied in the fall or early spring there will be no beetles coming
out in July and no grubs for several years. DDT at 6 pounds of 10% DDT
to 1,000 square feet will give an even longer grub-proofing effect. Our
plots so treated in 1944 are still grub-free. The possible trouble with
DDT is that it is too nearly permanent, and if you should plow up a
piece of lawn treated with it and try to raise tomatoes or strawberries,
you might find the soil too toxic.

~Biological control in the grub stage:~ The chemical grub-proofing of the
sunny parts of the front or main lawn on a property is desirable for the
reasons stated, but it does not usually stop more than a fifth of the
beetle production around the property, because there are usually plenty
of neighbors' lawns, pastures, public grounds, and other
beetle-producing turf areas nearby. How are you to reduce the beetle
crop on these places, mostly on ground you don't control? Here is where
biological control comes in, something which I feel will appeal to you
in this group. The parasitic insects known as spring Tiphia, imported
from the Orient and well established on hundreds of estates, golf
courses, and cemeteries around Philadelphia and New York, may be
introduced in your vicinity when grubs reach about 5 to the square foot.
The parasites, which are like flying ants, appear above ground in spring
and feed on honey-dew. The female burrows in the soil and attaches her
eggs singly to Japanese beetle grubs. A maggot hatches and consumes the
grub. I have charge of the distribution of these parasites in New York.
I like to liberate at