I guess the answer to this question depends on your perspective. If you are a homeowner, you hope that it is not a good year for grubs. If you are in the lawn service industry, you want the preventative products you applied earlier in the summer to have worked so the lawns you treated are protected, but you don’t mind the extra revenue that comes from selling grub control treatments, so you are hoping for a good year for grubs. From the grubs’ perspective, I guess they are hoping that it is a good year.
I often check with our franchisees in the areas where grubs are a problem to find out what they are seeing. Our franchisee in Oak Creek, WI, Phil Bowen is seeing active grubs in a couple of his lawns. We are also getting some isolated reports of active grubs in suburbs of Chicago. We have a couple offices in central Iowa and they are experiencing a major drought this year, so they have not seen any grub activity so far. The Mid-Atlantic states may have grubs, but they have had so much rain this year that any grub activity may be masked since the grass is growing well, recovering from any feeding. Damage could be seen if it turns dry for a couple of weeks.
The amount of rain an area receives has a direct effect on grub populations. It is possible that parts of the Midwest that went through a drought last year may have less activity this year as the populations of grubs were down last year. This is because female grubs rely on soil moisture to keep their eggs moist and viable.
Adult female grubs dig a small hole into turf and lay their eggs. If the soil is too dry, the eggs will dry out and die. If this happens over a large area, such as what was experienced last year in parts of the Midwest, the overall populations can be reduced. Granted, there are still many lawns that are irrigated, so plenty of grubs still made it, but overall, the populations can be reduced by drought.
We will just have to wait and see if it will be a “good” or “bad” year for grubs. The cooler spring and early summer may have pushed back the adult emergence, which in turn, may affect when the eggs hatch. Keep an eye out for areas of turf that appear to be turning brown when the rest of the lawn looks good. Do the “tug test” to see if the grass pulls up like a carpet. If so, you may have grubs.