Don’t Let Pesky Grass Defilers Conquer Lawn

Yes Virginia, buried out there beneath that thin blanket of dead grass, snow and muck, there is potential for a lovely green lawn. That is, if it wasn’t ravaged by moss, fairy rings or necrotic ring spot last year. If you had any of these grass defilers, you more than likely will have them again this year. To handle them takes fortitude, patience and some ingenuity.

Moss: Though moss gives a rich, earthy flavor to serene shady areas, moss does very little to enhance the beauty of grass. In fact, when it comes to a battle of wills between grass and moss, moss usually wins.

Moss is a shallow-rooted plant that thrives on wet, compacted soil. Compacted soil lacks oxygen that is essential for root growth. Foot traffic, machinery, rain, sun, and overwatering will drive out oxygen and compact the soil.

However, if moss is growing where the soil seems to be light and airy, perhaps the problem was a blanket of ash laid down by the eruption of Mount St. Helens 16 years ago. This gray dust has since worked itself into a thin layer a few inches below the surface of the soil. Because the ash is impervious to water, moisture may be trapped near the surface - a perfect bed for shallow-rooted moss.

So, how do we get rid of it? We can burn moss out with iron (ferric ammonium sulfate). But unless cultural conditions are changed, it will grow back.

Instead, open the soil to air by core aerating or jabbing a spading fork into the soil and moving it back and forth. This will also help break up hidden ash. In flower and vegetable beds, fluff the soil and add organic matter.

Open up shade areas to more light by thinning trees and shrubs. Check the soil. If it’s wet, don’t water until the top two inches are dry. Moss cannot live in dry soil. And finally, if you have bluegrass lawn competing with moss in a shady area, don’t bother trying to eradicate the moss. The moss will always win, so instead, remove the sun-loving bluegrass from this area. Even shade-loving fescue grasses have a difficult time competing with moss if the area is too shady.

Fairy rings: These are brown or deep-green rings in the lawn, often accompanied by mushrooms. Contrary to legend, they are not created by a group of fairies having nightly parties on your lawn.

If you were to remove the dead lawn, you would find gray soil filled with little white hairs. This is the fungus. Like ash, this gray matter is impervious to water. Water simply beads up and rolls off.

Since there are no fungicides registered for fairy ring control, we homeowners have taken it upon ourselves to come up with a cure. Judging from the following list, we’ll try just about anything: disinfecting the ring with bleach, as if the ring wasn’t pale enough; digging out two feet of infected soil and replacing it with new soil, only to have the problem back in a few short weeks; dumping straight Tide over the ring, followed by water; and if all else fails, fertilizing the ring to death with fish fertilizer or stale beer.

The trick to controlling fairy rings is breaking up the gray matter so water can move through the soil.

To date, there is only one treatment that does seem to work if the steps are followed very strictly every three days and not one step is skipped:

1. Poke holes about 2 inches apart and about 3 inches deep. A hand-held core aerator works well.

The holes should incorporate a foot of good grass inside the ring, the ring itself and at least 1 foot of good grass outside the ring.

2. Pour a surfactant over the area. A surfactant is a material that helps pull the water through the soil.

It can be as simple as one teaspoon of dish soap mixed in a bucket of water or special surfactants such as Schaeffer’s Aqua Turf or Oxyfresh cleansing gel.

3. Drench the area with water. Stand there with the hose until your sneakers are sopping wet.

The water, mixed with the surfactant, will move down through the holes, breaking up the fungus.

And you’ll need some good luck, as well.

Necrotic ring spot is a chapter all of its own. It’s such a depressing subject, we’ll discuss it on a cheery day, when the daffodils and tulips are in bloom.

, DataTimes