Lawn Insect and Disease Control is one of the most overlooked lawn care issues. Usually lawn insects and diseases cause great damage and frustrate all lawn care or lawn maintenance efforts. Lawn insects can be neatly divided into two distinct groups. Namely insects that feed above the ground, and insects that feed below the ground.
The two groups of insects cause two different types of damage to lawns. Insects that feed above the ground damage lawns by chewing grass plants or by sucking plant juices from grass blades. Insects feeding below the ground usually consume the roots of grass plants.
Numerous insects actually live in lawns and turf and if you observe your lawn carefully, you are bound to see a couple of different insect species. Luckily only a few can cause enough damage to be considered pests that require some form of control.
If we can start with above ground insects, several different types feed on grass by sucking the juices from growing plants. However because grass grows so rapidly, most insects that suck juices from grass never have any visible impact or cause any visible damage on a lawn. However it is worth noting here that the situation is very different when lawns are under one sort of stress or other, or when newly seeded. The visible effects and damage done can then be greater.
Insects that damage lawns include leafhoppers, mites, spittlebugs and chinch bugs. Usually only the last one causes severe enough damage to warrant control.
The leafhopper for example causes the chlorosis disease in lawns which is marked by yellow and white patches on green blades. This is caused by leaf hoppers sucking plant juices from the grass, as they do from all kinds of different plants. It is this sucking of juices that causes the grass blades on the lawn to lose color in patches. Leafhoppers, as the name suggests are long, wedge-shaped insects that hop (or fly) short distances from plant to plant. Leafhoppers will often be brightly colored and will have stripes.
On other occasions you may notice that grass blades on your lawn are blotched or stippled. You may even notice a silk-like webbing. This is usually caused by mites, which also suck plant juices on lawns. One mite pest, called the clover mite, leaves lawns and enters homes in spring or fall and is the only type of mite that may require control albeit inside the house and not on the lawn.
The other type of above ground lawn insect is the Spittle bug, whose name points to its’ action on the lawn. The insect will usually produce a mass of spittle and then hide inside it. Although some folks do not like the look of the spittle on their lawns, it does no harm to the lawn or people.
Let us now move to the most deadly above ground insect. This is the chinch bug, which we mentioned earlier. Adult Chinch bugs are about 1/8 inch long, are black in color and have white wing markings. Young chinch bugs are bright red with white spots across their bodies. This grass-blade-feeding pest lays its’ eggs near the grass roots, but as the grass dies, they move on to areas where the grass is still living. Damage usually spreads rapidly. Although hey prefer bent grass, they will usually feed on any sort of grass. Injury to lawns is most serious in hot dry weather where the lawn is subjected to full sun.
There is a simple test to determine if Chinch bugs are present. Get any can or metal tube with both ends open (you can cut off the other end of a coffee can or any other can). Place the can on the grass in an area where the lawn is in decline or yellowing. Twist and push the can firmly into the soil so that the bottom end goes into the soil by an inch or two. When this is done, fill the can with warm water. If chinch bugs are present, they will float to the surface withion about 5 minutes. You may need to keep on adding water so that the level remains above the grass.
The most effective way to control Chinch bugs is chemically and it is important to force the spray into the turf under high pressure to get the insecticide into the roots. Use Beauvaria Bassianca (a fungus), carbaryl, permethrin or imidacloprid.
Many people consider the sod webworm to be the most serious lawn pest. When fully grown, the sod webworm is about ¾ inch long and is cream or light brown in color. It usually has dark spots on its’ back.
Sod webworms usually live in silken rubes attached to the base of the plant. Signs of webworm disease in your lawn will often be areas of unevenly cropped grass. Later large areas of the lawn turn brown and die. They will usually hide in sheltered spots and only emerge in the early evening and on close examination of an infested lawn you will see them flying above the grass. Females will scatter eggs over the lawn as they fly.
There are to ways of telling the presence of sod webworm on a lawn. If you note large numbers of birds feeding on the lawn, this often indicates the presence of webworm larvae. The other way is a simple test which will conclusively indicate if there is a sod webworm infestation on your lawn.
Just pour a gallon of water containing ¼ cup of household detergent on a square yard of lawn. Webwarm larvae will come to the surface.
Chemical treatment will work best in June. This early season application will prevent build-up later on.
Some insects will cause damage to a lawn by nesting below the ground. These include ants and white grubs,
Ants are probably the most common. Although ants are beneficial soil insects, mainly because of their soil aeration activities and recycling of nutrients, they are also capable of causing great damage to any lawn. Some ants form hills around heir external openings, and ants can also smother grass or destroy grass roots. They also eat grass seeds.
However it is grubs, the larvae of several species of beetles, which are the most harmful below ground lawn pests. In the winter they will burrow deep into the soil but will come out in milder weather ill get closer to the surface and live at the grass root level feeding on the roots and killing the grass.