As part of our lawn maintenance programs we will monitor your lawn for the presence of chinch books and grubs and other insect pests and diseases. If we find them, we have orgainc ways of controlling them as well as recommendations for you, the homeowner, to avoid them in the first place. .
Grubs
Grubs live underground and feed on grass roots. Damage appears as dead grass that can be lifted like a piece of carpet. Grub damage usually shows up in August and into September; damage will first occur in the sunniest, driest locations of the lawn and can spread very quickly during dry conditions. To check for grubs, cut and turn over 1″ section of grass at the edge of a brown area. Grubs will be found within the top couple cm of soil. The grubs are milky white with a brown head and a darker tail. They will be curled up in a C shape and approximately ¾” long. You may also detect grubs when a hungry raccoon or skunk discovers them in your lawn and rolls up the grass to get at them..
Our method of killing grubs in your lawn organically involves applying beneficial nematodes to your lawn. Nematodes are microscopic worms that will kill the grubs. They are harmless to pets, cats, people, plants and anything except grubs. Nematodes are not selective and therefore attack a wide range of over 250 different root zones pests.
The Lite Gardener will apply the nematodes using water. Immediately following application, the lawn has to be heavily watered to wash the nematodes down into the soil where they can attack the grubs. The home owner must keep the soil moist for about three weeks after application because nematodes need water to survive. Nematodes die in sunlight and so we do the application early in the morning or early in the evening. We recommend aerating the lawn before an application of nematodes since it will help the nematodes get down into the soil to attack the grubs.
Chinch Bugs and Other Insects
As part of our lawn maintenance program we will keep an eye out for surface-feeding insects called chinch bugs. Adults are approximately ⅛” long and black with white wings and black triangle where their wings overlap. Larvae are tiny, bright red and have a white stripe on their back. The damage will first be noticed in dry sunny areas and spread out in irregular brown patches. They attack the grass in middle to late summer usually during dry conditions.
If we spot this kind of damage we will part the grass and look for chinch bugs on the soil and in thatch. We will look at how quickly the chinch bugs move since, earlier chinch stages are less mobile than later stages.
You can help avoid the chinch bugs by keeping the lawn watered in the summer. Chinch bugs need hot dry conditions for survival and reproduction and they don’t tolerate a large amount of water. As always, though, avoid over watering.
If chinch bugs are discovered early enough, soaking the sod with a solution of 75ml biodegradable soap mixed with 40 L of water per 5.5 ft², and covering the grass with a flannel sheet will help control the bugs which will will crawl to the tip of the grass.
If chinch bugs still continue to be a concern the Lite Gardener would recommend overseeding the entire lawn with resistant grass seed.
We would over-seed the lawn with a specially designed perennial ryegrass mixture. Perennial Ryegrass provides improved resistance to several grass insects and many grass diseases. Chinch bugs, in particular, do not like to eat perennial Ryegrass.
As a less preferred alternative, diatomaceous earth (DE) is approved for use against chinch bugs and certain other pests. DE absorbs the waxy layer on insects’ cuticle, causing dehydration and death. It also works abrasively to rupture insect cuticles, allowing cell sap to leak out and, if ingested, it disrupts the insect’s breathing, digestion and reproduction. There are no formal studies on application rates and effectiveness on chinch bugs. DE should be applied over the effected are, it takes several weeks or months to control pests. DE is non- toxic to humans but dust can irritate eyes and lungs so we would have to wear a mask when using it.