Zorro zoysia is a popular variety of zoysia grass that was developed at Texas A&M University. The appealing characteristics of the grass include its medium blade texture, shade tolerance and heat resistance, which is common to all zoysia types. Although zorro zoysia is resistant to a wide variety of insects and diseases, you can still encounter problems with zorro zoysia. Most issues that trouble zoysia are the result of poor lawn-culture practices.
Determine if animals have access to your lawn. These may include your own or neighbor's pets. Pets can cause nitrogen burns by urinating on your lawn. Signs of nitrogen burn from pet stains include round yellow spots of grass on your zoysia. To solve pet nitrogen burn, water the burned areas more frequently to leech the excess nitrogen from your lawn.
Dig up a plug of grass from your lawn and examine the cross section. If your zoysia lawn has a layer of roots and grass clippings that is more than 1 inch deep, it has developed a thatch problem. Thatch may be caused by too many fertilization sessions. Water and air cannot penetrate this layer of thatch. To remove the thatch in your Zorro zoysia lawn, run a dethatching machine over the lawn. A dethatching machine, which can be rented from many lawn stores, operates similarly to a lawn mower.
Time the amount of shade that your zoysia grass receives if it appears patchy in shaded areas. Zorro zoysia is a very shade-tolerant variety of grass, but it will not stand up well to full shade. Patchy areas should be overseeded with a full-shade tolerant grass.
Examine your lawn for low drainage areas. Areas of poor drainage can cause large brown patches that result from excessive moisture in the soil. Improving your drainage can remove these large patches.
Dig through the soil to find insects such as billbugs or lawn caterpillars. Billbugs look like tiny white grubs. They attack the roots of zoysia and cause it to turn brown in patches across your lawn. To remove billbugs and caterpillars, use an insecticide. B.T. is an insecticide that works particularly well on caterpillars. Insect parasitic nematodes may be released into your lawn to remove billbugs.