Great advice from Orrin Clayton:
Just thought that this information may be of use to you since our lawns have been torn up by the crows (and other creatures) digging for the grubs in our lawns.
There was an interview on CFRA this morning and the message was that application of the nematode to the lawn should occur only when the ground temperature exceeds +15C. In the mean time it appears that we will have to rake off the dead grass and reseed. The following may be of interest to you

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