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Sunday, 9 February 2020

How to get rid of white grubs in your lawn?

White Grubs

White grubs are larvae of beetles, such as the June beetle or the Japanese beetle, which feed on grassroots and organic matter in the soil. Over time, these worms turn into adult beetles, mate and lay their eggs in early summer. Most of these beetles have a life cycle of one year, but this can vary depending on the species and regions.

The eggs of these white grubs are incubated for two or three weeks and once born, they immediately feed on grassroots. Generally, they tend to live between 1 cm to  6 cm below the ground.

How do you detect the presence of white grubs?

  • Grass that is damaged by white grubs will start to turn yellow and die.
  • One way to tell if they are present is to observe the surface after the lawn watering because some worms will rise to the surface to breathe.
  • You will notice patches of dead grass appearing at random locations on your property. When grassroots are damaged, the lawn cannot absorb water properly which causes it to dry out and discolor.
  • Your lawn will be spongy and easy to lift. When grassroots are damaged, you can roll up the grass like a carpet. Look below to see if there are worms.
  • Your lawn will be very vulnerable to drought and other stressors.
  • Another sign of white grubs in your lawn is an increase in the presence of raccoons, skunks, and birds on your property. They feed on it.

Prevention tips

The best way to prevent a white grub infestation is to adopt good cultural practices to keep your lawn healthy. The healthier your soil, the less vulnerable it will be to an infestation.

Here are some preventive methods to adopt:

  • Add different types of grasses and clover to your lawn. White grubs love grassroots so if you add a variety of seeds, your land will be less attractive to these small insects.
  • Abundant but infrequent watering. This will allow the roots to grow deep so your lawn will be more resistant.
  • Mow your lawn to the ideal height.
  • Be sure to mow your lawn when it is dry, not when the soil is wet. Leave grass clippings on the ground!
  • Do not use chemical pesticides.
  • Promote natural fertilizers.
  • Aerate your lawn and apply a layer of compost in spring or late summer

How can you determine the level of white grub infestation?

Inspect your lawn to check for white grubs and determine the extent of the infestation. A healthy lawn can support up to five worms per square foot. Make small holes in different sections of your land and if you don’t find more than 5 worms per square foot, treatment will not be necessary unless birds or animals dig the soil to feed on it. If you find more than 5 worms, you will need to control the infestation. We also recommended that you take the worms you find and submerge them in a container filled with soap and water.

How do you control a white grub infestation?

  • Install a bird feeder to attract birds to your garden. They will take care of eating the white grubs in your yard.
  • Purchase nematodes, which are small organisms that feed on white grubs. They won’t damage your lawn. They should be applied towards the end of August or the beginning of September. Applying nematodes will reduce your infestation problem, but this method will get rid of all the worms!

Careful: Make sure to read the instructions carefully so that you know how to apply them to your lawn!

  • You can also apply milky spores, a natural solution that comes in the form of granules. It creates a bacterial environment in the soil known as milky spore disease. This solution works best to get rid of the Japanese beetle larvae.

Good to know: Milky spore disease is not an immediate solution. Indeed, it can take between 1 to 3 years before the effects start to be noticed. It’s an effective long-term solution though!

  • Avoid watering your lawn too often. White grubs need a lot of moisture to grow and survive. Deep and infrequent watering is recommended. 
  • The best way to get rid of white grubs in your garden is to contact a lawn care specialist.

If you have a white grub infestation, contact Forever Green and our team of professionals will set up a control plan to get rid of these insects quickly and efficiently!