Question
We live in Texas with lots of Japenese Beatle grubs as well as fire ants.   We were considering using both beneficial nematodes(faster acting) and milky spore (slower acting but last years?) The ad for beneficial nematodes (Antidote trade name) claims they help kill the beatle grubs, as well as fire ants and fleas ( fleas are no problem for us).   Our only concern is are the beneficial nematodes also going to damage the "good critters" such as  earthworms, etc.   If, so then we should probably stick with just milky spore which appears to be grub specific  

Answer
Rod,

Nematodes won't hurt earthworms (see http://www.livingwithbugs.com/ent_nems.html for info). Milk Spore will work for Japanese beetles but it is slow acting (see http://www.livingwithbugs.com/japanese_beetle.html for info about Japanese beetles). The fire ants should be treated separately with baits and individual mound treatments (see http://www.livingwithbugs.com/fire_ant.html and follow the link to control info). I really don't think you'll get a good level of control of fire ants with the nematode product.

Post a follow up if you have questions.

Jack DeAngelis
http://www.livingwithbugs.com