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tracted by the light, and in flying around it drop into the tub and 
are killed by the oil. 
Outdoor plants, such as cabbages, beets, and onions, may be 
protected by the use of poisoned bran mash, the formula for which 
is given on page 155. This should be placed in small piles, about a 
tablespoon ful to a pile, at the bases of the plants. When a field 
which has been in grass is to be planted to vegetables, it is well to 
use the poisoned bran in spring, shortly before planting the crop. 
Dusting or spraying plants with Paris green or arsenate of 
lead is effective against cutworms and safe for most vegetables, but 
not for lettuce. 
It is often easier to pick, brush, or shake off cutworms than to 
destroy them by poison. 
In agricultural practice, early fall-plowing is often helpful if 
done while cutworms are still actively feeding. Their food being 
thus destroyed, many will starve, and others will be too weak to 
survive the winter. On the other hand, if the plowing is delayed 
until the cutworms have pupated, little or no benefit will follow. 
Crop rotation may sometimes be useful, but as very few garden 
plants are unmolested by cutworms, it is not to be relied on. Xev- 
ertheless. if it can be avoided, the more succulent plants should not 
be grown in soil known to be infested by cutworms. 
Clean culture is, of course, important. Weeds and rubbish af- 
ford excellent breeding places for cutworms as well as for many 
other insects. 
The Lettuce Plant-louse 
Macrosiplium lactuccu Kalt. 
(Nectaropliora lactuccu, Siphonophora lactiiccc, Aphis laciuccc) 
The lettuce-louse is probably to be found in every Illinois green- 
house where lettuce is grown. It often becomes very abundant, 
especially in the lettuce heads, and not only stunts the plants, but 
makes the product unsalable because it is impossible to free the 
heads thoroly from the lice. I have also found this louse on celery 
out-of-doors, but never sufficiently abundant to do injury. 
Its life history is the same as that of most other plant-lice; that 
is, the viviparous female reproduces without the intervention of the 
male, and gives birth to living young. Each louse may produce 50 
to 100 young, and because of this great reproductive capacity a 
greenhouse may be almost overrun before the presence of the in- 
sects has been noticed. 
Natural Bncmics. — Fortunately, this species, like most plant- 
lice, is subject to the attacks of many parasitic and predaceous in- 
sects which do much to control it. They are seldom capable of 
