February, ’23] 
CORY: DUSTING FOR PEA APHIS 
81 
the tops, causing them to turn yellowish white, wilt and die, thus stunt¬ 
ing the growth of the onion. 
During 1915, 1916 and 1917 they were extremely abundant in the 
vicinity of Olney. When one approaches infested plants the capsids 
scurry to the ground and seek shelter under rubbish or in cracks in the 
ground, and so abundant were they when these observations were made 
that they almost covered the ground in the garlic fields as one walked 
through them. Figure 4 will give some idea as to their abundance on 
the plants. 
They were seen at various other points in the southern half of the 
State, but serious injury was noticed only at Olney. Wherever garlic 
fields are present the insect may well become a limiting factor in the 
protection of onions. 
Whale oil soap used at the rate of one ounce to a gallon of water killed 
both adults and nymphs almost instantly. And where garlic fields had 
been burned over or plowed under in the fall, practically no capsids were 
present the following year. 
President Sanders resumed the Chair. 
President J. G. Sanders: Thenexton our program is “Pepper Mag¬ 
got, a New Pest of Peppers and Egg Plants,” by Alvah Peterson. 
PEPPER MAGGOT, A NEW PEST OF PEPPERS AND 
EGG PLANTS 
By Alvah Peterson, New Brunswick , N. J. 
(Withdrawn for publication elsewhere) 
President J. G. Sanders : We will now listen to a paper on “Dusting 
for the Pea Aphis,” by E. N Cory. 
DUSTING FOR THE PEA APHIS 
By Ernest N. Cory, State Entomologist, College Park , Md % 
Abstract 
Dusting is most promising for pea aphis control. The principal tests were to 
determine the most effective percentage of nicotine. A high nicotine content and 
not less than 30 lbs. of dust per acre are preferable. The use of a trailer of can¬ 
vas is advised. There should be at least 50 percent of the vines infested when 
dusting is begun. 
Dusting seems to hold the greatest promise in the economical control 
