Kr. Day et A. Cameron, EFFECT OF CONTEMPORARY INFESTATION BY THE SPRUCE APHID (ELATOBIUM-ABIETINUM) ON ROOT-GROWTH IN SITKA SPRUCE TRANSPLANTS, Forestry, 70(1), 1997, pp. 1-5
The short-term relative effects on root growth of aphids living on the
needle leaves of spruce transplants were examined experimentally. Ult
imately, aphids cause the loss of foliage and so defoliation was simul
ated in two of the treatments. Aphid populations at a density frequent
ly reached in forest conditions, caused no relative inhibition in root
growth over a 62-day period. Aphids were expected to have a longer te
rm impact, however, since artificial defoliation had significant effec
ts on root development.