In his weekly Call of the Land report Alberta Agriculture pest specialist Scott Meers says that diamondback moths could be a season-long threat, especially in southern Alberta where emergence was so early this year. The first adults of the new generation have been spotted around Lethbridge this week.
"This is really early, these generations will get faster as the weather gets warmer so we could easily see three generations and possibly into the fourth this summer," Meers said.
Meers said that is less likely further north where diamondback development has been slower, but this is a scenario for significant crop damage, as each generation gets larger and the population is higher. However parasitic insects and diseases could reduce the population, and some adults of parasitic moths are being spotted.
"It’s going to be an interesting study on how this population plays out," Meers said.
He said there are still reports of cutworm damage. The threat is diminishing as southern crops advance, " But in central Alberta we need to be… keeping our eyes open for those bare patches that may develop due to cutworms."
Scouts looking for cutworms have been finding a white grub with distinct legs and a brown head. Meers said this is not a cutworm but the larval stage of the dung beetle. Its presence is related to high organic matter, manure in three fields and and beet residue in another. They will start disappearing over the next few weeks, Meers said.