Do you have problems with a patchy, browning lawn despite the fact that you have carefully watered, planted, and fertilized the grass? If so, you probably have lawn grubs. Grubs are small, worm-like insects that are actually larval stage Japanese beetles, European beetles, or Oriental beetles. The grubs live under the surface of the ground and feed on the roots of grass. In turn, patches of grass begin to brown and die. If left unchecked, the grubs can easily destroy an entire yard. It is often difficult to completely eliminate grubs, but using these techniques can drastically reduce their numbers and give you a greener yard. Note: All of the treatments mentioned are most effective during the month of August. This is the time when grubs are the weakest and closest to the surface.

Be sure grubs are your problem

A simple way to confirm there are grubs present in your lawn is to dig up a small section of grass and count the grubs you find. A count of more than 20 grubs per square foot usually means there is an infestation. It is normal to have a few grubs in your yard, so if this is the case you may need to look into other sources of dying grass.

Plant a thicker lawn

The adult beetles seek out areas of thinner grass to lay eggs, so your lawn is more likely to remain untouched if it is too thick for the beetles. This can be achieved by seeding the lawn every spring and fall.

Only water when needed

The eggs and larvae need high moisture levels to thrive. Only watering your lawn when it is needed will reduce the population with the added benefit of lower water bills!

Use a natural predator

Parasitic worms called nematodes can reduce a grub population by 50% to 80%. They work by feeding and completing their life cycle inside the grubs’ bodies. Caution should be used as these worms can also eliminate other species of insects. Do plenty of research before trying this method to get rid of grubs.

Kill them with bacteria

Bacillus popilliae, commonly referred to as Milky Spore, can be used to kill grubs that are still relatively young and close to the surface. The best time to apply Milky Spore is around August as this is the time when grubs are the closest to the surface. This will not eliminate all of the grubs, so treatments may need to be administered several years in a row to be completely effective.

Pesticides

The use of regular pesticides on grubs is not considered very effective. It is difficult to apply at the proper time of the year as the grubs may be too large or too deep in the soil for the pesticide to kill them.

By using the strategies outlined above, you can transform your patchy lawn into the lovely, green lawn you’ve always wanted. It will take some time and dedication, but the results will be worth the work.

Image Credit: http://www.ent.iastate.edu/soybeaninsects/node/347