Black pineleaf scale density per meter of ponderosa pine needles.
| Needle age | |||
|---|---|---|---|
| Treatment | 2002 | 2001 | 2000 |
| Control | 97.75 (s.e. 27.28) | 178.25 (s.e. 37.26) | 113.50 (s.e. 19.99) |
| October 2001 | 39.18* (s.e. 13.03) | 91.47* (s.e. 16.60) | 119.82 (s.e. 27.50) |
| March 2002 | 22.06* (s.e. 6.87) | 70.00* (s.e. 15.21) | 87.59 (s.e. 16.45) |
↵* Significantly different from control (2002: p < 0.006; 2001: p < 0.027).