I used to have such a severe grub problem that they practically destroyed my yard. And besides the grubs, moles came looking for an easy and plentiful meal thus helping to tear up my yard. I researched and talked to anyone who knew anything about the blasted creatures. A VA Tech extension agent suggested that in order to get rid of the moles I had to get rid of their food source which were grubs. He said that Milky Spore would rid my yard of grubs and would last for up to 15 years. Milky Spore is rather expensive but I gave it a try. You can apply it anytime but I would not apply it during the dry summer months. It will not hurt plants or animals since it is organic. Guess what, the stuff really works. I applied it to my yard about 14 years ago and have had no grub or mole problem since. Am getting ready to bit the bullet and pay for another treatment. You can buy it in powder or grandular form. I purchased powder and had to drop a teaspoon of the stuff every 3 feet in my yard. It then needs to be watered into the ground. Just Google Milky Spore and it will take you to web sites where it can be purchased. Its also available at many garden centers.