DISCUSSION
The lowest plant establishment rates (64% and 53%) were in the earliest and latest planting date,
respectively, and may have been due to weather events surrounding the plantings. In the week of the first
planting date (25-May), northern Vermont had 5.67 inches of precipitation above normal, according to
USDA weather data from Burlington, VT (30-year average from 1961-1990). The week of the second
planting date (1-June), which had the highest emergence rate, also had above average rainfall, but slightly
lower than the observed increase one week earlier (3.92 inches above normal). The final planting date (7-
June) fell within a week that had 7.62 inches of rainfall, or 4.66 inches greater than normal. While the
entire spring planting season had high precipitation (for example, the five weeks between 16-May and 19-
June included 23.45 inches greater than historical averages), significant rainfall events occurred during
the weeks of the first and last planting dates, possibly accounting for lower emergence rates and eventual
populations.