By: Island County Extension Agent, Donald B. Meehan
HOME LAWN CARE
Many of us look out across our lawn and shudder at the sight. It is all too often covered with weeds or moss and is worn out in various places. It needs mowing and you probably are wondering if it needs fertilizing.
These are only a few of the problems that can be encountered in trying to have a beautiful lawn. Some of the others are damage from European Crane Fly larvae, thatch buildup, Fairy Rings, and disease.
In this column I plan to focus on moss and weed control and choosing the right grass species. Having an understanding of these things will take you a long way toward having that showpiece lawn that both you and your neighbors will admire.
Let's talk about moss control first, since I have more questions on that issue than any other. Mosses are green plants similar to algae, but somewhat more advanced. They are able to manufacture their own food. A key thing to remember about them is that they grow best during the time when your lawn grasses are dormant. That is during the fall, winter and early spring.
Generally we tend to think that moss is there because of excess watering. So, we try reducing our watering rates in the spring and summer so we don't encourage the moss to grow. Unfortunately this never eliminates the moss problem. Moss does like water, but only during its growing season. By holding water back in the spring and summer, the problem is aggravated because the grass is weakened. To reduce the chance that moss will grow, you need to provide a shade-free lawn area and create the most fertile situation for grass to grow. If you have a strong stand of grass, as you enter the fall season, moss will have a difficult time getting started.
If you have moss in your lawn now, you can begin ridding yourself of it by raking as much of it out as possible. The better the job you do the greater the chance you'll be able to eradicate it. Next step is to apply commercial iron compounds. The most common is Ferrous Sulfate or Ferrous ammonium Sulfate. In order for these substances to do their best work, you want your lawn to be as free of moss as possible.
The next step in controlling moss is to have the right grass species planted. Four types of grass are most often used. They are bentgrass, turf-type fescues, turf-type perennial ryegrass and Kentucky Blue grass. In recent years, WSU researchers and turf specialists are finding Kentucky Blue grasses less favorable for Western Washington. The primary reason rests in their inability to fend off winter lawn diseases during their semi-dormant season. The grasses that are finding the greatest favor for low maintenance care and durability are the fescues and perennial ryegrasses. Bentgrass provides a nice textured lawn surface, but tends to form thatch at a faster rate than the others. The fescues are lower maintenance since they require less nitrogen and the perennial ryegrasses tend to green up early in the year and stay that way longer.
Kentucky Blue grass tends to do better in high traffic areas because of its sod forming root structure. Unfortunately Kentucky Blue grass lacks good shade tolerance. The fine leaved fescues are probably the best grasses for shady lawns. Perennial rye grass fits between fescues and Kentucky Blue in shade tolerance. Remember, moss does better in shady areas, so a vigorous species needs to be used, such as a fescue, to compete against the moss.
When selecting a grass seed mixture, determine the conditions that the grass must withstand. Then select a mixture that will favor those special conditions. For the average lawn that you don't want to spend a great deal of time fussing over, select a mixture that has 20% or less of Kentucky Bluegrass. The best mix will be a 50/50 mixture of turf-type perennial ryegrass and fine leaved fescues.
WSU research has found that the variety Manhattan is a good turf-type perennial ryegrass variety. Other successful varieties are Diplomat, Omega, Acclaim and Yorktown II. There are many varieties of fine leaf fescues to choose from. Instead of me trying to list them all, you can contact me for a free copy of a list I've prepared that includes all types of grasses tested by WSU researchers.
Selecting the proper variety o varieties will make a significant difference in the life and appearance of your lawn. If you have a lawn that is a mess now, you may want to go about re-establishing it. This will give you a chance to fit the grass variety to the conditions you have.
The last subject I want to address deals with weed control. Weeds are surely one of the biggest problems I see. The main reason they are a problem is that the grass is not competitive enough to keep them from starting. So the key to a weed-free lawn is to have a vigorous, hardy grass using up all the space, light and water.
Most of the lawn weeds we see are biennials or perennials. In other words, they have an excellent root structure that will provide lots of energy to the plant to keep it growing even if you cut the top off. They can be controlled by pulling them out, but success will be dependent on the vigor and competitive nature of your lawn. If your lawn is mostly weeds now, then you will be fighting a hard to win battle.
Many of us prefer to take the simple way out and use herbicides. There are a great number of them on the market. Most are designed to kill broadleaf weeds and generally contain 2,4-D, Dicamba (Banvel) or MCPP. When using any form of herbicide, whether liquid or granular, be especially careful to read the label on the product container. The herbicides mentioned are most commonly used in the fertilizer and weed killer lawn foods. These same herbicides, which kill your dandelions, may also kill your landscape shrubs or trees. All of them can be absorbed by the roots of plants.
If you plan to spray on a herbicide your problems double. When spraying you want to avoid having the chemical mist drift onto your favorite flower bed. Of course any of these herbicides will also be taken up by the roots, even if sprayed on.
For a show place lawn you will want to have planted the most hardy grass variety for your home's particular growing conditions. You will want to provide your lawn with adequate fertilizer three or four times during the year and you will want to mow it regularly.
There are many questions which I have left unanswered. If you want to learn more about lawn care and maintenance, contact the Extension office for a publication called HOME LAWNS, EB 0482 ($.25) or LAWN WEED CONTROL EB 0607 ($.25). There are approximately twenty different Washington State University publications available on lawns that deal with insect and disease control to lawn renovation. We carry a supply of those, as well.
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