As August seems to be the month high on most people’s list for pests, I think I will concentrate once again this week on dreaded bugs! However, this time lawns are my topic for consideration. Not how to keep them weed-free, but grub free! If you see large patches of brown appearing in your lawn for no apparent reason or if skunks and/or raccoons are tearing up the turf while you sleep – you can rest assured that you have a few grubs munching away on your grass roots.
It is important to understand what grubs are and how their lifecycle works in order to completely eliminate them from your lawn. The most damaging grubs you are likely to encounter in your lawn are the larvae of the European Chafer, Japanese Beetle and June Bug.
You will recognize these grubs by their curled-up ‘C’ shape, creamy-white bodies, brown heads and dark brown tails. These destructive grubs burrow deep down into the soil during the winter months. As the temperature rises in spring they move upwards and start feeding on grass roots. By mid May they move deeper into the soil to pupate, then in June emerge as fully-fledged beetles, only to return once again into the soil to lay eggs beneath the turf.
Each of these beetles is very different to look at. The European Chafer is light tan, Japanese Beetles are green and orange and June Bugs are black and shiny.
Now we come to the time for action. The best time to control the emerging larvae is when they are small and feeding near the surface. If you have recently noticed brown patches in your lawn, especially in areas of strong sunlight, this could be an indication of grub damage. From late July to mid August the newly hatched grubs will feed enthusiastically on grass roots, sometimes also plant roots, and will continue to do so until the cooler weather in the fall forces them to move deeper into the soil.
According to Wilson and C.I.L. in Brantford, an expert on lawn care, if you suspect you have a grub problem a good way to check is to lift a section of your lawn with a spade. You will see them wriggling around in the soil as soon as they are exposed. If you can count five or more grubs per 30cm sq. then you need to consider using a pest control product. If you have less than this, say just one or two, then he suggests you would be better off to concentrate on a good lawn care programme.
They suggest a product called ‘GrubOut’ for effective control this time of year. ‘Grub Out’ is designed to be watered deeply into the root zone where the grubs are feeding. After you apply it, be sure to water your lawn for at least 3 to 4 hours to make sure that the grub control product has moved down to the root zone. This is available in a liquid concentrate or attach-and-spray format. It is important to read the instructions given with the product for advice on coverage and quantities to use for effective control. Proper application of a grub control product in August, with a further application in September to control late developing larvae, will help break the cycle and significantly reduce grub populations in spring.
June Bugs spend two years as a grub. In the third year they complete their life cycle and emerge as a beetle. Japanese Beetles and European Chafers can fly, and have a one-year cycle. In this case control will be required on an annual basis where grub populations are high.
‘GrubOut’ can also be used to control Chinch Bugs and ants (refer to the label once again!).
Chinch Bugs can cause severe damage to your lawn by sucking the juices out of the blades of grass, causing areas of the lawn to totally dry out and die. Test for Chinch Bugs if you notice yellowish-brown, irregular patches in dry sunny areas of the lawn. Remove the top and bottom from a large can, such as an empty coffee tin, press it 3-5cm into the soil at the edge of one of these patches. Fill with water, and keep it filled for approximately ten minutes. The blackish brown insects, 3.5 cm in length with white on their wings that float to the surface of the water, ar
