VARIEGATED CUTWORM (Peridroma margaritosa).
This is a climbing cutworm damaging to both garden and greenish crops. The ash-
colored to brown larva is mottled with darker brown and has a pale yellow
dot on most segments. It winters as a pupa, and in spring the gray-brown
moth lays masses of eggs on stems or leaves of low plants, on twigs,
or on buildings. The larvae climb up stems to eat holes in buds, flowers,
leaves, or fruits.
Control. If you are setting out only a few plants, a stiff paper collar
around each stem, extending an inch into the soil and 2 inches above, will
keep them from harm. Working 10% chlordane into the soil before planting has been helpful. Plants can be sprayed or dusted with DDT. Many
cutworm baits are on the market, most of them having Paris green or
sodium fluosilicate as a base, but in using them there is some danger of
poisoning birds or pets.
Damping-off is the name given to collapse and death of young seedlings
just before or soon after they emerge from the ground. Several soil fungi
are responsible. Seed can be started in vermiculite or sphagnum, which
are practically sterile as far as harmful organisms are concerned. Ordinary garden soil used for starting seedlings in flats can be disinfected by
sprinkling 21/2 tablespoons commercial formaldehyde mixed with a cup of
water over a bushel of soil. Mix it very thoroughly, fill the flats, let
stand 24 hours, plant seed, and then water.
For outdoor planting we usually treat the seed, a slight coating of
chemical on the seed coat holding the fungi in immediately surrounding
soil in abeyance until the little seedlings get a good start in life. Seed
treatment is insurance. If soil is friable, temperature favorable, and seeds
germinate quickly, there will often be a good stand without treatment.
But if the weather is damp and cold and it takes the seedlings a long
time to come through the ground, they are very likely to damp-off. Lima
beans almost never do well without a seed protectant. Semesan, a mercury compound, was formerly popular as well as red copper oxide, but
now two or three newer materials, Arasan, Phygon XL, and Spergon (now
given the common name of chloranil) suffice for most purposes. The
amount of chemical used is very small, not over 54 teaspoon per pound
of seed. For a packet of seed take just a bit on the end of a knife point, add
it to seeds in a jar, shake well until every seed is lightly coated, then
turn out on a screen to remove excess dust.