My lawn is being ruined as there are areas where the grass is going yellow and dying. I've discovered that birds are pecking at the lawn and retrieving big white grubs, which I think may have caused the patches. Our local groundsman tells me there is nothing I can do to kill these grubs. Is he right?
Brad: As you have already discovered, the chafer grubs (the larval stage of the chafer beetle) will eat the roots of the lawn grasses, causing the grass to turn yellow and die out in patches (often very large areas). The trouble is that, once the local bird population know where the grubs are, they will dig up the lawn to find and eat them - making matters worse.
The groundsman you spoke to would have been right in the past – there used to be nothing you could use to get rid of them, as there were no chemicals gardeners could use to control these pests, until now. The best way to eradicate the grubs (and stop birds visiting) is to use the system insect control Provado Lawn Grub Killer from Bayer Garden, which is harmelss to children, pets and wildlife. It consists of a chemical which is applied to the soil, but can only be taken up by grass roots, and kills the grubs as they touch it or feed on the roots. The good thing is that you only need to apply this once a year, usually as soon as you notice the damage.