Table 1.
Estimated amounts of B. thuringiensis subsp. kurstaki applied in Fairfax County, VA, and remaining at the time of sample collection
| Wk sampled | Size (km2) |
B. thuringiensis subsp. kurstakia |
||
|---|---|---|---|---|
| Estimated amt (g) applied | Estimated amt (g) remaining | Estimated no. of spores remaining | ||
| 0 (after spraying) | 0.737 | 5,460 | 5,460 | 1014 |
| 6 | 4,000–5,000 | 1014 | ||
| 12 | 3,000–4,000 | 1014 | ||
| 24 | 1,000–2,000 | 1014 | ||
| 48 | 500–1,000 | 1013 | ||
a
The amount applied assumes 7.4 kg of viable B. thuringiensis subsp. kurstaki per km2, a one-time application. For the amounts remaining, the lower number assumes a 100-day half-life and the higher number assumes a 200-day half-life. The number of spores remaining assumes 1011 spores/g.