Growers need to be on alert for apple scab infection period this week. (Photo: K. Peter)
Protection is needed for vulnerable green tissue; a copper spray will be useful for trees not at green tip.
The Polar Vortex the last couple of weeks gave us a little bit of a reprieve…but now, Mother Nature can no longer be held back. Spring has sprung: many trees are showing green tissue and the scab spores are mature and releasing.
There most likely will be a couple of dry times in between to allow for spraying.
The average temps will be on the warmer side, which will lessen the number of leaf wetness hours needed for scab spores to cause infection. Green tip is a vulnerable time for scab and it is important to be vigilant, especially in blocks with known history. Once scab gets established, it is very challenging to get ahead of the disease.