How to Get Rid of Lawn White Grubs: A Comprehensive Guide

Are you noticing patches of thinning grass in your lawn? Is your lawn becoming a playground for skunks, raccoons, and moles? These could be signs of a lawn grub infestation. Lawn grubs, the larval stage of certain adult beetles, can wreak havoc on your beautiful lawn if their populations grow out of control. But don’t worry, we’ve got you covered. This comprehensive guide will show you how and when to get rid of lawn white grubs effectively.

Understanding Lawn White Grubs

Before we dive into the methods of getting rid of lawn white grubs, it’s important to understand what they are and the damage they can cause. Grub worms are not actually worms but rather the larval stage of insects such as chafers and beetles. These larvae feed on the organic matter in the soil, including the roots of your grass. As they munch on the roots and crowns of turfgrass, they can kill your plants and create unsightly patches in your lawn. Furthermore, as grown beetles, they can also eat the leaves of any plant they come across, making them a threat to your garden as well.

Signs of a Lawn Grub Problem

While all grass can tolerate some grub feeding, it’s important to be aware of the signs that indicate a problem. Here are some common signs of a lawn grub infestation:

Patches of thinning turf: Dead patches of grass that appear and grow larger each week.
Easy grass removal: Grass that can be pulled out easily from the roots.
Animals digging in the lawn: Skunks, raccoons, moles, and crows digging in search of grubs.
Presence of beetles or moths: Flying insects low to the ground, looking for a place to lay their eggs.
Bouncy feeling when walking on the grass: This indicates that the roots have been damaged.
Signs of drought in the grass: Even though there is sufficient water, the grass shows signs of drought stress.

Scouting for Lawn White Grubs

To be certain that you have a lawn grub problem, it’s important to scout for them. Follow these steps to identify the presence of white grubs on your lawn:

Cut a one-foot section of your lawn using a shovel or a lawn edger in an area where you suspect grub activity.
Peel up the soil from the cut section. If there is grub damage, the grass will peel up easily.
Sift through the soil, counting the number of grubs you find.
Tally the count. If you find 10 or more grubs per square foot, you have a serious grub infestation.
Repeat the process in other areas of your lawn to ensure accuracy.

Preventative Methods to Get Rid of Lawn White Grubs

Prevention is key when it comes to dealing with lawn white grubs. Here are some preventative methods you can employ to keep your lawn grub-free:

Dethatching: Keep thatch to a minimum by fertilizing your lawn with nitrogen only once a year, strategically and judiciously, usually in late October or early November.
Aerate your lawn: Regularly aerate your lawn to break up compacted soil and prevent grubs from infesting the thatch layer. Aeration also encourages root growth.
Mow your lawn strategically: Keep your lawn properly mowed using the highest setting on your mower (around 3.5 to 4 inches). This promotes deeper root growth, making your lawn more resilient to grub damage. If you mow high and use fertilizer in the spring, you may not need to apply a grub killer.
Choose the right turfgrass: Opt for tall fescue grasses, as they are more tolerant of grub populations compared to Kentucky bluegrass and perennial ryegrass.
Deny moisture to the grubs: Keep your lawn dry during July and August, which will cause beetle eggs to dry out and die. If your lawn starts to brown, water more; no residual damage will occur.
Chemical insecticides: Consider using effective preventive grub treatments such as imidacloprid, thiamethoxam, and clothianidin. Apply these pesticides from mid-April to mid-June, depending on your location. It’s important to note that the use of insecticides poses a risk to people and other beneficial insects, so be cautious and consider mowing your lawn just before applying to avoid attracting pollinators to the treated area.

Curative Methods to Get Rid of Lawn White Grubs

If you’re dealing with an active grub infestation, curative methods come into play. Here are some ways to treat grubs on your lawn:

Curative chemical insecticides: Use products like carbaryl and trichlorfon to treat the grubs once you’ve noticed their presence. These are short-lived products that provide immediate results. Treated grubs will turn yellow or brown within a week, so monitor your lawn to assess the effectiveness of the treatment.
Milky spore disease: Consider using milky spore disease as a grub treatment, particularly for Japanese beetles. However, it’s important to note that milky spore disease is a weak pathogen that results in only 20% to 25% infection at best.
Neem oil: Neem oil is an effective and safe pesticide against grubs. Mix neem oil and water according to the label instructions for a DIY solution. Spray your yard with the solution in late summer or early fall.
Natural enemies: Promote the presence of naturally occurring pathogens in the soil, such as fungi, bacteria, and protozoa, which kill or weaken grubs. Ground beetles, ants, parasitic wasps, and flies are beneficial insects that feed on eggs and young grubs.
Beneficial nematodes: Consider using insect parasitic nematodes as a curative lawn grub treatment. However, using nematodes effectively requires expertise and experience, as they are only effective when used in the right way and at the right time.

When to Treat Your Lawn for White Grubs

The best time to apply preventative grub control products is from mid-April to mid-June, or generally during summer or early fall when the eggs have not hatched yet, and the grubs are still small. If you miss this time window, apply a curative treatment as soon as you notice the first signs of grub damage.

When to Call Pest Control Professionals

If you find more than six grubs per square foot in your lawn, it’s a good indication that you should take action and treat your lawn for grubs. Don’t wait until you have a serious infestation. Skunks, raccoons, and other wildlife may not adhere to the threshold and can cause significant damage even with a lower number of grubs. Consider calling local pest control professionals to help you eradicate the grubs and prevent further damage to your lawn.

The Life Cycle of Lawn Grubs

To better understand how to combat lawn grubs, it’s important to familiarize yourself with their life cycle. Here’s a breakdown of the life cycle of lawn grubs:

In summer, insects lay eggs, typically in late June for European chafers and July and August for Japanese beetles.
One to two weeks later, the eggs hatch and the young grubs begin feeding on grass roots.
As the summer progresses, the eggs die off due to dry soils and moisture stress.
In winter, the grubs burrow deep into the soil and overwinter.
In spring, the grubs burrow upwards to the grassroots and resume feeding.

Identifying Lawn Grubs

To effectively combat lawn grubs, it’s important to be able to identify them. Here’s what lawn grubs look like:

White grubs are cream-colored with a brown head, have three pairs of short legs, and a soft body that is usually curled into a C shape.
Adult beetles, which are the mature form of grubs, can be green, tan, brown, or black and range in size from 3/16 of an inch to 1 inch.

Types of Lawn White Grubs

While there are different species of lawn grubs, they all cause similar damage to your lawn. Here are some common types of lawn grubs you may encounter:

Japanese beetle grubs: These widespread invasive insects have white grub larvae found in lawns across the country. Japanese beetles are typically seen mating at their feeding sites during the day.
Asiatic garden beetles: Light brown as adults and white with a brown head as grubs, these beetles are similar to other white grubs. They are known to be overtaking Japanese beetles in some areas of the eastern U.S.
Chafer species: Led by masked chafer beetles, such as the European chafer, these beetles also contribute to white grub infestations. European chafers conduct mating flights at dusk near trees or chimneys.
May beetles: Also known as June bugs, these beetles are part of a large family called scarabs. They can cause significant damage to lawns.
Black turfgrass ataenius: This shiny black adult beetle is mostly found on golf courses but can also infest turfgrass in residential areas.

FAQs about White Grubs

Don’t lawn grubs play a positive part in a lawn’s ecosystem?

While grubs do contribute to the breakdown of thatch and organic matter in the soil, their populations can grow out of control and cause damage to your lawn. They eat the roots and crowns of turfgrass, ultimately killing the plants.

Is lawn damage a sure sign of lawn grubs?

Lawn damage can be an indication of grub infestation, but it’s essential to confirm this by checking if the grass pulls up easily from the roots. Additionally, lots of adult beetles on the lawn in July and wilting and browning areas in August and September are signs of possible grub damage.

Does the browning of a lawn mean there are grubs?

Browning of the lawn can be a sign of grub damage if the grass pulls up easily. However, if the grass is firmly rooted, another underlying issue may be brown patch disease.

Conclusion

Lawn grubs can be a serious threat to the health and appearance of your lawn. By understanding their life cycle, identifying the signs of infestation, and implementing preventative and curative methods, you can effectively get rid of lawn grubs and restore the beauty of your lawn. Remember to monitor your lawn regularly, take action at the right time, and consider seeking professional help if necessary. You can keep your lawn grub-free and thriving all year round with proper care and attention.

Get in touch with EcoLawn now for specialized help with your lawn. We focus on eco-friendly solutions that make your lawn beautiful while being kind to the environment. Visit our website or email admin@ecolawnutah.com to schedule and start making your lawn thrive sustainably!