74 BULLETIN 479, U. S. DEPARTMENT OF AGRICULTURE. 
near the surface of the soil. They feed at night, concealing them- 
selves in the soil or under rubbish during the day. Scratching the 
soil about an injured plant to a depth of one or possibly two inches 
usually reveals the worms, and this method of hand destruction of 
the larvae may be practiced in small areas where the infestation is 
scattering. 
Cutworms may be destroyed also by means of a poisoned bait 
prepared and applied as follows: Mix 50 pounds of bran with 4 
pounds of lead arsenate and 2 gallons of low-grade molasses until 
the mass is made into a stiff dough. The chopped oranges or lemons 
mentioned in the bulletin referred to (see footnote) are not always 
essential, but the molasses is absolutely so. In semiarid regions it 
is advisable to add water to prevent rapid desiccation and to dis- 
tribute the bait toward evening. About a tablespoonful of the bait 
should be placed every foot or two along the nursery row. In case 
of migration from an adjoining field, the nursery may be protected 
by running a narrow band of the poisoned bait entirely around the 
edge or along the side nearest the source of infestation. A ditch 
constructed around the Savenac Nursery proved somewhat effective 
in trapping some of these larva? which were migrating from an ad- 
jacent clover field. 
WHITE GRUBS. 1 
White grubs, the larvae or young of beetles commonly known as 
May beetles or " June bugs," are often a serious menace to nursery 
stock, especially conifers, injuring or killing the seedlings and 
transplants by cutting off the smaller and girdling the larger roots. 
Most of the May beetles have a three-year life cycle, and except the 
one or two months (usually May and June) during which the beetles 
appear above ground to mate and feed, this entire period is spent 
underground, and two years of the three are spent in the grub stage. 
In the extreme northern limits of the United States, that is, in 
northern Wisconsin and Minnesota, where the grubs are important 
enemies of conifer seedlings and transplants, this insect has a four- 
year cycle, due to the shorter seasons. The grubs occur at various 
depths in the soil, and their proximity to the surface is largely 
dependent on the temperature and moisture conditions. They are 
found deeper during the winter months and more often quite near 
the surface in early fall. Plowing or cultivating the soil at this 
time, therefore, is of value, especially if done the year following the 
most severe summer injury, which would be the season the insects 
are transforming from grubs to beetles, at which time disturbances 
1 For further information on these insects, see U. S. Dept. Agr. Farmers' Bulletin 
543. 
