Like every other living thing, lawns can get diseases. They sometimes arise and can cause untold devastation when lawns are stressed and the conditions are right. Most of these diseases occur in the summer, during extended periods of hot, humid conditions. Even the healthiest of lawns may struggle to thrive.
In this article, we will highlight the most common lawn diseases and their causes.
Brown Patch: Mostly found in tall fescue and ryegrass, brown patches affect many cool season grasses and some species of warm season grasses. Brown patches are notable for their distinctive “smoke rings” that are sometimes visible on the outer edges. Brown patches occur during extended periods of heat and humidity, especially when nighttime temperatures remain above 68 F. Poor air circulation, overwatering, over fertilizing and lawn compactions can also make them worse.
Dollar Spot: One of the most common lawn diseases, the dollar spots gets its name from the distinct pattern of dead circular patches about the size of a silver dollar. They can occur when moisture is present during the warm day/cool night patterns of spring and fall. Excessive thatch, poor drainage, overwatering and low soil fertility can all aid in bringing on dollar spots.
Powdery Mildew: Often found on Kentucky bluegrass lawns located in shady areas with limited air movement, powdery mildew looks like a white dust covering the grass blades. Although it can yellow the turf over time, powdery mildew is not likely to cause widespread damage to a lawn. Extended cloudiness can bring on powdery mildew but if the problem is not weather related, conditions may need to be altered for a healthy lawn. Shade tolerant grass species are not likely to attract powdery mildew and pruning or thinning trees can improve air circulation and sunlight to the area.
Fairy Ring: Fairy rings can present themselves as dark circles or partial circles on the lawn, and they may or may not grow mushrooms. There are many stories about digging out fairy rings but the widespread nature of the fungal spores leads to limited success trying to dig the rings up. Maintaining a lush green lawn can blend in the darker color and regular mowing can help control the presence of mushrooms.
Snow Mold: Prolonged snow cover in the spring can lead to grey snow mold or pink snow mold, especially if the ground is not quite frozen. It can also occur on over fertilized lawns and under leaves left over from the fall. Snow mold damage is largely superficial and temporary; the best way to deal with it is to rake it out to help the area dry. New growth will begin and soon the damage will be gone.
Red Thread: A common and relatively harmless lawn disease, red thread usually appears when the lawn is due for fertilizing. Chances are if red thread is present, it’s time to fertilize the lawn. Red thread is noticeable by its distinctive red hairs amongst the turf giving it a pinkish/red appearance from a distance.
Being aware of these diseases and take care of your lawn to avoid them!