How to identify and control black beetle damage in lawn

Author: Jon Lamb   Date Posted: 7 March 2018 

At last, a simple and much safer solution for controlling black lawn beetles.

During summer and early autumn, far too many Adelaide lawns are regularly bombarded with chlorpyrifos (an extremely toxic and environmentally damaging chemical) in an often futile attempt to control black lawn beetles and their witchetty grub-like larvae.

The alternative is to spray the lawn with a relatively new but very low toxic systemic chemical containing imidacloprid (Confidor, Bug Kill, Conquest and others). In this case, the aim is to kill the black beetle larvae in spring well before they begin damaging your lawn by feeding on their roots.

Black beetles overwinter in lawn grass before mating and laying eggs anytime during spring. During late spring and early summer, the overwintering generation of beetles dies.  Meanwhile, the grubs or larvae that started life early in spring begin to emerge as lawn foraging beetles. At this stage, it’s possible to have both adults and larvae feeding on your lawn and if the problem is ignored, dead lawn patches quickly appear.

Imidacloprid is new aged technology designed to kill soft bodied and sap sucking insects at a very low concentration.  When it is mixed and ready to spray, it has a very low toxicity to humans and animals. However, being systemic, it is absorbed by the roots of lawn grasses and while it kills all root eating lawn grubs, it has no effect on other beneficial insects in the soil. Imidacloprid remains active in the soil for up to three months.  This is a major breakthrough as an infestation of either lawn beetles or lawn grubs (or both) can occur over an extended period.

Quick guide to lawn beetle attack

A preventative spray with imidacloprid is warranted if

  • You experienced serious damage (bare patches, loose turf (easy to pull)) from either lawn beetles or lawn grubs last season.
  • You observed or observe large numbers of black beetles in your lawn this spring.
  • Large numbers of birds continue to land on your lawn and appear to be feeding (on lawn grubs).
  • You find very large numbers of witchetty grub-like larvae in garden beds adjacent to your lawn (five to six grubs per spadeful).

When to spray

  • The best time to spray your lawn for beetles and beetle larvae is October and March.

What to use

  • The best product on the market for home gardeners is Yates Complete. It contains 2 active ingredients - one being the imidacloprid I have already mentioned for the control of the larvae, and the other is called Cyfluthrin which will conrol the adult beetles.

Is it really lawn beetles?

Bare patches caused by lawn beetles and their larvae are easily confused with a range of management issues including

  • Compacted soil
  • Poor (uneven) watering
  • Annual weeds with a spreading canopy coming to the end of their growth cycle
  • Lawn diseases.

Experienced gardeners are quick to point out your best defence against black beetles is a well managed vigorous lawn. A healthy lawn can tolerate low populations of lawn beetles and their larvae

Comments (34)

Will this product be harmful to birds feeding on t

By: on 25 June 2021
My husband is very keen to get rid of African lawn beetle, but we have crows and magpies feeding on the grubs/beetles. Will this product harm them? Thank you

Paul Munns Instant Lawn Response
Hi Rose Thanks for your query No, the birds will be fine Thank you

Black bettle

By: on 22 March 2021
Large black beetles spotted in February, now March and small black beetles seen. Half of my lawn is dead with large patches of dirt and easily pulled out roots what would be the best product to use? The rest of the grass seems untouched Do I spray all the lawn, including the “healthy” section?

Paul Munns Instant Lawn Response
Hi Shane Thanks for your enquiry We have a product called Yates Complete. I would definitely recommend to spray the whole lawn

Dog Safe?

By: on 16 April 2020
We have a lot of African Army Beetle and my husband has used numerous chemicals to get rid of them to little/no avail. I am starting to think our dog's scratching (he has sensitive skin) may be a result of these chemicals. Is Yates Complete safe to use around dogs? And if not, can you suggest something else that is safe for dogs please?

Paul Munns Instant Lawn Response
Hi Sally Thanks for your query Yes, Yates Complete is safe to use around dogs. Just allow a few hours drying time

Beetle larvae

By: on 15 February 2020
When it rains, i have large amounts of grub like creatures on my sidewalk and porch. The sidewalk is covered. I've been told they are ground beetle larvae. We are having a very warm and wet February. Will this work on them and prevent beetle infestation in the spring??

Paul Munns Instant Lawn Response
Hi Hope Thanks for your query You can use a product called Yates Complete, this will control beetle larvae and last in the soil for up to 3 months and shouldn’t need reapplying until Spring Regards......Andrew

Beetles and larvae in my lawn

By: on 13 January 2020
Hi, was wondering why my lawn had dead patches - and we called in the gardeners. They confirmed that parts of the lawn are infested by lawn beetles. When I was pulling out weeds I can see some larvae as well. Reading the thread above - would using the Yates complete work on these? Thanks and great website.

Paul Munns Instant Lawn Response
Hi Rich Thanks for your question. Yes, Yates complete is the product we recommend to control both the beetle and larvae in your lawn. This will last for 3 months per application. Cheers.....Andrew

Black Beetle

By: on 2 December 2019
What can I use now to kill black beetle. I have dead patches every where on my lawn

Paul Munns Instant Lawn Response
Hi Teresa We recommend using either Yates Complete or Brunnings Lawn Grub and Beetle Killer to control both the Beetle and Larvae. Thank you

black beetle in garden and lawn

By: on 21 September 2019
I believe that by using complete that should look after the lawn, but these beetles are also in my garden, what should I use here. Thanking you in anticipation, John

Paul Munns Instant Lawn Response
Hi John Thanks for your enquiry. Unfortunately this product doesn't mention the use of it in garden beds. So we can't recommend it. There may be other beetle killers out on the market that can. Good Luck.

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