Welcome back to the Wonderful World of Weed Man! This week we are continuing our bugs series, “I Found an Alien in My Lawn!” Last week we began our series with an article about chinch bugs, “Treat Chinch Bugs with a Shop Vac!” This week we will be writing about grubs.
Grubs, aka White Grubs, aka Billbugs – are the #1 cause of insect damage on lawns in the Treasure Valley. Grubs are small, plump, white larvae which chew on grass roots. They are the offspring of billbugs – a type of beetle. Although the billbug itself as an adult won’t damage the lawn, their offspring will. If you are seeing a lot of billbug beetles in the spring, you can be sure of potential problems in the summer.
The life cycle of a grub will depend on the time of year it hatches. A late hatching in the year, will often overwinter in the soil as larvae. In the spring it will emerge, continue to feed again, then become an adult beetle. The adult will repeat the cycle. There can be up to 3 hatchings each summer.
As grubs continue to grow and feed the damaged area becomes larger. Once the roots are destroyed the lawn will have patches of yellow appear. It looks like the beginnings of a lawn drying out. Unfortunately, the grubs are actively feeding on the lawn during the warmer parts of the year. The combination of time of year and how the damage presents results in many homeowners assuming that their lawn just needs more water.
By assuming it needs more water, you will up your watering times or the number of times you water – which could result in a whole host of other lawn problems. Your lawn will begin to look worse by allowing the grubs to continue to damage the lawn and potentially introducing fungus/disease in your lawn by over-watering. You can see the quandary you will have on your hands that needs to be remedied.
Here are some examples of grub damaged lawns:
So how can you tell that you have grubs? One of the signs you have an issue would be animals! Your friendly neighborhood raccoon might be visiting your lawn for what they would consider a tasty treat! Skunks, raccoons, and birds will show up to your lawn looking for a meal. Grubs are a natural food source for these critters. Although it is nice that animals will eat the grubs, but they will damage the lawn in the process – so the natural way to treat grubs isn’t the best option for your lawn.
Another way you can tell you have grubs is from the damaged area itself. When you begin to see the yellowing in the lawn, you want to inspect the damaged area. If you can pull up on the damaged area and it peels up like freshly rolled sod, something has been chewing on the roots. The roots are no longer there to connect it into the soil. A good way to compare if it pulls up easier than normal is to go to a healthy part of the lawn and pull with the same force to see how different it feels.
Typically, if you inspect the damage area where it meets the healthy part of the lawn you will have a greater likelihood of seeing the grubs when you roll up the grass. This is an example of what you might see when you look:
So you found grubs, now what? Well, the best option is to treat preventatively. There are preventative grub controls available. This is ALWAYS the best option. Think of it as an immunization for the lawn. It won’t prevent billbugs from entering your lawn. It won’t prevent billbugs from laying their eggs in your lawn. It won’t prevent the eggs even from hatching. However, it will take out the grubs once they start feasting on your lawn. It will knock them out quickly as well. Preventative Grub Control is a preemptive first strike on grubs! If you can take care of them before they damage the lawn you will save yourself a lot of time and headache fixing the damage they could have caused.
It is important to know that If you have had grubs in the past you have an 80% chance of having grubs again in the future. Many grubs will return to the same area they were hatched in to lay their eggs. Even if you have never had grubs in the past, it is still important to get a preventative treatment. Your neighbor may have had grubs. Grubs are no respecter of property lines. In fact, the adult billbug can travel up to ¼ mile in a day. You never know when they might show up.
If you failed to do a preventative treatment for grubs, or if some still slipped through the preventative treatment you will begin to see damage on your lawn. At this point you want to take care of the cause of the damage before it spreads or becomes worse. A curative treatment will be needed to take care of the grubs.
It is very important to realize that a curative treatment for grubs will do nothing for the lawn other than kill the grubs so they do not continue to feed on the lawn. IT will not repair the damage. If your grass is healthy and the damage is limited, it may fully recover on its own. If the damage is severe, you will need to think about over-seeding your lawn in the fall. We have a great article on how to repair your lawn: “Lawn Repair or Replace”.
If you think you have a grub problem on your lawn, give us a call! www.weedmanboise.com 208-888-9911 #wecareforyourlawn