Table 1.

Summaries of 3 TBZ (thiabendazole) efficacy trials showing percentage of canopy with beech leaf disease and percentage of canopy with fine twig dieback. BLD (beech leaf disease).

Study locationTreatment% canopy with BLD1% canopy fine twig dieback2
202220232024P-value3202220232024P-value4
Aurora, OHTBZ (n = 10)70.5 (8.4) a521.0 (8.3)b16.9 (8.0) b0.000112.0 (4.7) a11.7 (2.2) a10.9 (2.4) a0.9704
Nontreated (n = 10)58.0 (10.6) a37.0 (10.2) a44.4 (10.4) a0.40537.5 (2.4) a17.7 (4.3)a18.7 (4.5)a0.0917
Chardon, OHTBZ (n = 10)n/a59.5 (6.6) a9.3 (4.1)b<0.0001n/a20.5 (3.8) a14.0 (3.1) a0.1964
Nontreated (n = 10)n/a69.6 (4.9) a61.5 (8.6) a0.4241n/a17.0 (2.8) a17.0 (4.2) a0.7556
Hillsborough, NJTBZ (n = 10)n/a48.0 (7.0) b80.0 (8.5) a0.0093n/a26.0 (2.7) a7.4 (1.5)b<0.0001
Nontreated (n = 10)n/a36.7 (3.7) b70.3 (6.5) a0.0002n/a25.0 (1.9) b48.8 (8.0) a0.0088

  • ↵1 Average visual estimate of the percent canopy with beech leaf disease symptoms over time where the standard error of the mean for each year is in parentheses.

  • ↵2 Average visual estimate of the percent canopy with fine twig dieback over time where the standard error of the mean for each year is in parentheses.

  • ↵3 P-value is based on a repeated measure analysis of variance (ANOVA)(Aurora, OH) or paired T-test (Chardon, OH, and Hillsborough, NJ) for treatment groups independently at each location across all years where the estimated percent canopy with beech leaf disease symptoms was the response variable.

  • ↵4 P-value is based on a repeated measure analysis of variance (ANOVA)(Aurora, OH) or paired T-test (Chardon, OH, and Hillsborough, NJ) for treatment groups independently at each location across all years where the estimated percent canopy with fine twig dieback was the response variable.

  • ↵5 Letters following each year represent levels that are statistically different based on a Tukey’s HSD (Aurora, OH) or Student’s T-test (Chardon, OH, and Hillsborough, NJ) post-hoc means separations for both % canopy with BLD and fine twig dieback independently for each treatment group at each location.