The winds of spring 2013

Last week, a colleague was looking at the Environment Canada daily weather data for Ridgetown for April and May 2013.  He noticed that there were very few days where the maximum gust was less than 31 kph (the cutoff they use for publishing maximum gust values).

The factsheet Pesticide Drift from Ground Applications states that to avoid drift, we should not be spraying when wind speeds are below 2.0 or above 9.6 kph.  Graphs of the hourly wind speeds for April and May 2013 shows that there have been very few windows of opportunity for spraying this spring. On these graphs, the horizontal bars show the minimum and maximum wind speeds for responsible spraying and the vertical lines are midnight.  Not surprisingly, most of the periods of calmer winds occurred closer to midnight.

Horticultural crop producers are often the losers in a spring like this.  Again this year, we are likely to see too many incidents of crop damage due to spray drift.  Perhaps someone said it best in a tweet that I saw on May 15. “Even the no-till fields are blowing across the road today. Yet my competition is still spraying. Bunch of jack***es.”