available but need to be improved, particularly for the cabbage 
aphid. 
Onions 
The most destructive pests of onions are the onion thrips, which 
draws the sap from the leaves and damages the blossoms, and wire- 
worms and the onion maggot, which feed on the bulbs. Any one of 
these insect species may cause crop failure. Prior to 1914 no 
satisfactory contrel measures were available, and the damage by 
the onion thrips alone was estimated at about 27 percent of the 
crop. Since that time the widespread use of DDT has greatly ree 
duced these losses. For example, grewers of onion seed report 
that under conditions of heavy, thrips infestation they could pre- 
duce from 200 to 00 pounds of seed per acre before DDT was used, 
but by using DDT they can produce from 1200 to 1500 pounds. The 
yield of bulb onions has been increased as much as 10,090 pounds 
per acre. On the basis of these increased yields, it is estimated 
that the loss due to onion thrips was reduced to about 10 percent 
during the period 196851. The average loss for the period 19))2—51 
was about 17 percent, or about $10,527,000 annually. No data are 
availeble on losses from wireworms or the onion maggot, 
Peas 
The pea _ aphid is the major widespread pest of peas in the United 
States. It sucks the sap from the leaves and trensmits several 
mosaic diseases. In 1938 it caused losses ranging from 5 to 0 
percent in different parts of the ccuntry. 
Some of the other insects that damage peas, usually in limited 
areas, are the pea weevil, pea moth, beet armyworm, cutworms, seéde 
corn maggot, thrips, and leaf miners. The pea weevil is probably 
the most important, as its grub feeds in the immature seeds, making 
the green and dry edible peas unsuitable for the market and the 
seed peas nonviable. Pea weevil damage is limited chiefly to areas 
where large acreages of peas mature in the field. In Washinetor 
and Oregon where most of the dry edible peas are grown, the loss 
amounts to 2.); percent of the crap, or about $636,000 each year, 
In addition, it costs about $12);,000 annually for insecticides, 
and $90,000 for application. The annual loss from damage to the 
vines by application equipment averages about $160,000, 
Peppers 
Peppers are attacked by many of the insects that attack tomatoes 
and potatoes. The principal pests are cutworms, flea beetles, and 
the green peach aphid. The pepper weevil, which formerly was very 
destructive in Californias, caused relatively little damage during 
the period of 192-51 owing to imprceved control messvres estinated 
to have given California growers a net profit of $594,000 in 19h1 
alone. However, this weevil spread to Georgia during the nericd, 
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