Let's Talks About Grubs!

By Megan Harrigal |

Let's Talks About Grubs!

Let's talk about bugs! Well... specifically grubs. What are grubs, how do you know if you have them, and how do you get rid of them? Below are some basics for you to learn more and find ways to help solve your grub problem and restore your lawn to its lush and healthy state.

 

First, what even is a grub?

Grubs are the larval stages of different types of beetles including Japanese beetles, June beetles, and European chafers. They are distinguished by their soft, light-colored bodies that curl up when disturbed. Grubs feed on organic matter including grass roots, which can be devastating for your lawn. These larvae lay dormant during winter months, becoming active as the weather starts to warm up and can remain active through the fall. [1][6]

 

How do you know if you have a grub infestation?

There are a few ways to recognize infestations before they become out of control. The most common way to spot if you have grubs is if there is yellowing, drying, or browning of patches of grass in your lawn; some people describe it as if their lawns are drought-stricken. Especially, if these patches grow, despite watering, and you notice other pests digging in your lawn. If you notice these signs, you can test your soil by digging up a one foot square patch of turf around 2"-4" deep and peeling back the layer to reveal the amount of grubs, if any, that you have. One or two grubs alone does not indicate an infestation and can be normal (make sure to retest with another area of soil to confirm); but, if you have more than 10 grubs per sq. foot of turf, you have an infestation and probably should treat your lawn before it gets worse. Usually, your lawn will roll up like a carpet if you have a bad infestation as well, as the grubs feed on the grass' roots. [2][6]

 

How do you get rid of grubs, and prevent them from coming back?

Grubs do not go away on their own, so it is essential that infestations are treated! But, do not worry! There are effective all-natural treatments that disrupt grubs' life-cycles and can help you rid your lawn of these pests for good.

  1. No matter what type of grub infestation you have or the season, dethatching and aerating your lawn can help with all of the following treatment options. Dethatching is best done when your grass is actively growing and the soil is not too dry- For cool season grasses, the best time to dethatch is in the early spring or fall. For warm season grasses, dethatch in late spring to early summer. [3][7]
  1. Grubs LOVE moisture, so we recommend switching from traditional fertilizers and watering your lawn a few times a week, to liquid fertilizers like Gnome's Organic Lawn Fertilizer Plan, to better control your lawn’s moisture and give it only the water it needs.  Added bonus…getting rid of excess moisture can do wonders for not just grub infestations, but also fungi and mold problems. [3]
  1. Depending on where you live, introducing a predator to grubs can be another great option. Some pests, like raccoons and moles will dig up your yard and are more of a symptom than a treatment for grubs. However, birds make a great natural predator! Some people swear by backyard chickens, which will naturally peck at grubs, but other species life woodpeckers, blue jays, and robins will happily eat them for you as well. Adding bird feeders or baths can attract these birds in the wild if chickens are not an option. But beware, these birds need to dig into the ground to get to the grubs. [3] 
  1. Another natural option is introducing milky spore. Milky spore is a bacterium that specifically targets Japanese beetle larva, meaning it will only work on eliminating this species from your lawn. Milky spore can usually be bought at your local garden or farm supply store, and is best applied in fall, when the temperature is between 60° and 70 °F and when your lawn is moist. Note: milky spore can take time to work, and should be applied several times a year for 2-3 years to ensure biological control and to make sure infestations do not come back. Milky spore is non-toxic to kids and pets, but make sure to follow safety instructions for application. [1][4]
  1. The last recommended natural treatments for grubs are more DIY. For smaller infestations, some people simply hand pick at the grubs, which can help the problem, but should not be used as the sole treatment. Additionally, many people may not want to have to resort to this. If using this method, make sure to place grubs in a glass jar with dish soap to ensure the larvae drown. [5]
  1. Some people also report luck with a homemade solution of Borax. For using Borax, add 1 Tbsp of Borax to a spray bottle of warm water (approximately 32 oz) and spray on your lawn. This may provide short term help with infestations but should be used with caution as Borax contains Boron, which can actually kill your grass if used in excess. [3]

If nothing else works, there are pesticides containing chemicals like chlorantraniliprole, carbaryl, and trichlorfon that can greatly aid with infestations, but these only target specific species and need to be applied at certain times of the grub's life cycle to be most effective: generally, chlorantraniliprole in the spring, and carbaryl and trichlorfon in the early fall. Additionally, these pesticides are toxic and need to be treated with caution; it is recommended to leave this up to the professionals for proper application to keep your family safer. [1][2][3]

Finding an effective treatment for your lawn's infestation depends on different factors, and there are pros and cons to each method, which should be considered before treating your lawn. Regardless of season, climate, grub type, or other environmental factors, we recommend dethatching and aerating your lawn as well as limiting the amount of moisture it receives by switching to an organic liquid fertilizer, like Gnome's Organic Lawn Fertilizer Plan. Finally, make sure to recheck your lawn yearly to prevent re-infestation!

 

 

(1) https://www.aphis.usda.gov/plant_health/plant_pest_info/jb/downloads/JBhandbook.pdf

(2) https://extension.unh.edu/blog/2019/09/how-do-i-treat-grubs-my-lawn

(3) https://smithspestmanagement.com/blog/post/how-to-get-rid-of-grubs/

(4) https://lawnlove.com/blog/milky-spore-for-grub-control/

(5) https://www.gardenguides.com/130385-things-kitchen-rid-lawn-grubs.html