Table 3.

Statistics of girdling time for categories of elms observed to have Dutch elm disease.

CategoryNo.Percent of totalGirdling time (min)
MeanStandard deviation
Convoluted20335.0**2.059
Nonconvoluted
  10-20 in. dbh17282.5**0.881
  21-38 in. dbh24393.5**1.215
All elms611003.71.749
  • a**Means significantly different from each other at the 0.01 level, student’s t test.