Question
My lawn is infested with grubs.  I live in New Jersey.  I understand that since it is already mid-September, if I am to treat it, I need to do this right away.  I am not entirely sure what type of grass I have.  My questions are 1)How do I know if the lawn is permanently damaged, or if it will come back next Spring?   2)If I treat for grubs now, should I also plant new grass seed, and if so, how long should I wait to plant new grass seed after the grub treatment?   3)If the lawn is permanently damaged, should I just plant the grass seed, and treat for grubs next Spring?   4)What products do you recommend?   Thank you

Answer
Controlling grubs in fall can be very difficult. They are probably too big and mature to be affected. If you decide to control them now make sure it is a product which works on contact. E.g. such as diazinon, isazophos (=Triumph) and trichlorfon (=Dylox, Proxol) have been the most successful. Check lables carefully to ensure you find the right active ingredient (not all products contain the same active ingredients). Be sure to irrigate well after the application in order to keep the grubs near the soil/thatch interface and to wash in the pesticide.

You can resow grass immediately.

Next spring, apply an early preventiative application. Do this in April/May. Use any product which contain imidacloprid (=Merit), or isazophos (=Triumph). Bayer Advanced All Season Long Grub Control or Scott's Grub-X both contain Imidacloprid (Merit). These products are good as preventiative meassures if applied timely. They are not effective in fall, so do not use it now.