Lawn Grub in the Domestic Lawn
So you have spent weeks preparing and caring for your lawn, and it is paying off! It has finally become beautifully lush and green, and is like a carpet! A little brown patch appears… you think maybe it just needs a bit of water, or maybe a little bit of fertiliser burn has occurred. No panic… put the sprinkler out for 20 minutes or so and she’ll be right! Over the next few days, the brown patch becomes bigger and bigger and is spreading across your lawn! Every green keeper’s worst nightmare, lawn grub! Now, in Queensland there are a couple of different types worm we commonly refer to as lawn grub, they are White Curl Grub and Army Worm.
White Curl Grub
The first lawn grub is actually scarab beetle larvae which is the juvenile stage of lawn beetle. So really, white curl grub is incorrectly referred to as a ‘lawn grub’ or ‘witchety grub’. These white curl grubs are a serious lawn pest and the signs of infestation are easily confused with other pests, diseases and disorders in turf. The end result of a white curl grub infestation is basically, yellowing to browning and ultimate death. White curl grub will eat away at the root system of turf which in turn causes death, with a serious infestation, you are often able to roll your turf up as the root system is completely destroyed!
White Curl Grub
Every lawn in Queensland at this precise time will have some white curl grub present and an infestation is generally regarded as a problem when there are 25 or more grubs existing per square meter. If less, a normal and healthy lawn with seasonal growth will sustain any damage caused. However, other external influences may likely exacerbate the problem, such as heat or drought conditions. If you have concerns, the best way to check for lawn grub is to grab a hessian bag or piece of old carpet and lay it on the grass in the late afternoon. Wet the bag or carpet thoroughly and leave overnight. The following morning the lawn grub will have been drawn to the surface, and an assessment can be made.
The second lawn grub critter is known as Army Worm. The adult lawn armyworm takes the form of a greyish-brown moth with a wingspan of 35 to 40 mm. Damage from these guys differ slightly from the white curl grub, as they work similar to that of other caterpillars, eating away at the leaves of the turf and damage is often seen as a clear line of dying grass marching across your yard. Often starting closest to the house near external light sources, which attract the adult moth. Determining if you have an Army Worm problem is the same process as above with the white curl grubs. However, be aware that if you have had some reasonable damage occur you will need to be smart with your test placement. Obviously, the grubs will have already moved on from the ‘dead patch’ and will now be working in the green lawn.
Now if your thinking they won’t get you because you care for your lawn and it is the healthiest in the street… I have news for you! These annoying little guys aren’t interested in your neighbours’ unsightly mess of a yard. The lawn grub have champagne taste, and won’t settle for the sparkling wine! So, unfortunately, the house with the nicest lawn is generally who gets hit the hardest!
Acelepryn GR provides ongoing protection from lawn grub for up to 6-months. It can also eradicate cutworms, armyworms and sod webworms. Acelepryn is ideal for larger areas and long-term pest control. This is why we recommend Acelepryn. Acelepryn provides safe and effective control of these bugs while minimising the impact on the environment and non-target organisms, such as bees and earthworms. Therefore, now is a great time to spread it and protect your lawn.
Acelepryn insecticide provides season-long control of grubs and caterpillars in a single application. The efficiency and longevity of performance of this product mean your lawn is free of trouble for longer and because Acelepryn is exempt from poison scheduling, personal protection requirements are reduced. As well, Acelepryn GR is a non-spray option, which means it’s easier to use.
Acelepryn kills the larvae of Black Beetle, which are present from about November to March, so an application of this for treating Black Beetle is best applied in September.
Pests such as insects and caterpillars remain a threat to your lawn through autumn, but they’re easily controlled with the right choice of insecticide. A little knowledge about the lifecycle of these pests aids in the decision. With products such as Acelepryn and Grub Guard, you can protect your lawn against attacks for many months.
Prevention is the key to avoid lawn grub! Unfortunately, most commercially available pesticide is designed to treat an existing problem of lawn grub, rather than prevent it from occurring. Although some of the granular mixes can be present for a little while after application, so will inadvertently prevent… for a short time at least! It’s the old adage, what came first? The chicken or the egg? Well, in this case, the moth! The first place to start is ensuring your eaves, house and fences are all free of moth nests. These range in appearance but mostly look like little cotton-like cocoons. The best attack is with a hose and a broom. This is by no means a guarantee, but at least you are limiting the amount of moths activity around your property.
Now the most effective treatment for an existing infestation of lawn grub is, unfortunately, a chemical approach. Both Bifenthrin and Chlorpyrifos seem to be the most most effective treatments and can be found in ready-to-use hose bottles, liquid concentrates for spaying and a granular form to be sprinkled and watered in. Be extra careful with these forms as they can also be lethal for other animals that may come in contact, including children! The best approach is to treat late afternoon when birds are less active. The birds are attracted the wriggly (and dying) grubs which come to the surface of the lawn after treatment. The most important thing to remember when using ANY chemical type control is to always read the label and apply at the recommending rates. It is important when treating an infestation to break the lifecycle. Treatment is recommended over a 2 week period – once on the first day, again on day 7 and then again on day 11. This breaks the cycle of cocoon – moth – egg – grub – cocoon… etc.
As a little bonus for this treatment, these Active Constituent are often present in many commercially used products for treating Ants and other insect activity. So while you get the benefit of ridding your beautiful lawn of those pesky grubs, you should also see reduced numbers of Ants, lawn Beetle, African Black Beetles and Cockroaches!
A natural approach generally relies upon carnivorous birds. There are a number of methods including flooding with water, and also soapy water, which will encourage the lawn grub to the surface, where they will hopefully be picked off by such birds. As you can imagine, this method can yield some rather sketchy results!
Good luck and remember to keep an eye on your Lawn!