Penetration of Oak Canopies by a Commercial Preparation of Bacillus thuringiensis Applied by Air

1990

S. 173-179

1 Abb., 5 Tab., 14 Lit. Ang.

Unselbständiges Werk

200091737

The volume of spray deposit throughout an oak canopy was measured at a single-leaf resolution. Profiles of deposit (international units per cm2) are compared for upper- and lower-canopy levels and positions within these levels. Droplet sizes and densities are shown for upper- and lower-canopy levels. Artificial targets were used to measure the deposit at ground level, the deposit on a horizontal profile at midcrown, and the deposit over a vertical profile from the canopy top to the ground. No significant differences were found between the levels or positions inthe canopy (P>0.05). However, highly significant variation was shown among sample trees (P<0.001). The distribution of dose among individual leaves was shown to be highly variable with approximately a lognormal distribution.