GRAIN APHIDS IN NEW BRUNSWICK: III. APHID POPULATIONS IN HERBICIDE-TREATED OAT FIELDS

Abstract

From similar initial populations, aphid infestations became higher in herbicide-treated areas of oats than in similar untreated areas. Fewer coccinellids were present in these treated areas. The inclusion of an aphicide with the herbicide applications held subsequent populations of aphids to the level of those in untreated plots. Although populations as high as 250 aphids per tiller occurred, no reduction in yields of grain or straw was found in 1962 or 1963.