You may not be playing golf on your lawn but that’s no reason it can’t look great
Story by Garry V. McDonald
I’ve never been overly lawn proud; I focus on the flowers. But I do want my turfgrass to be presentable and not a disgrace to the neighborhood. Maybe my turfgrass colleagues have slowly corrupted me? At any rate, after “What do I plant in that spot?” the second most frequently asked question I get is, “What’s wrong with my lawn?” This is a vexing question because so many factors come into play. I try to boil it down to animal, mineral, or vegetable.
By animal, I mean anything that walks, crawls, tunnels, or flies be it two, six, or eight-legged, or no legs. Is the damage caused by eating, digging, or generally just messing things up? Because my garden is an earthworm’s paradise, my lawn is a martyr to moles. Moles feast on earthworms, so they tunnel like mad and create “runs,” which at best, make the surface uneven, or worse, collapse in heavy rain leaving the landscape looking like a WWI battlefield. Repellants are available, but must be re-applied after rain, heavy dew, or irrigation cycle. When I was growing up, farmers used strychnine bait, but more often than not, they poisoned the neighbor’s pets. The best solution might be a good feline ratter or a dog of the terrier tribe.
Speaking of, dogs can be hard on lawns. If Fido is a digger, sometimes creativity is in order. My old three-legged dog insisted on beating a path through a perennial bed to drink from the goldfish tank. So we compromised: I re-arranged a few plants and added a flagstone access path for him. Never had another problem. Another dog was content to dig her foxhole behind a dense shrub, so no harm there. Both were raised as “garden dogs,” so maybe that was the difference. If the pup takes their job as head of garden security seriously and patrols the perimeter, creating a path using soft materials (cedar shavings, bark, or pea gravel) with plantings or lawn on the inside edge of the path can solve the trampled turf problem. Pooping scooping is a must to prevent ammonia salt burn and other unpleasant conditions and parasites.
While white-tailed deer view most of the flower garden as a smorgasbord, they usually aren’t much of a problem for the lawn. But the armadillos! Now that’s a different story. One of God’s more obstinate critters, once they take a notion to dig up the lawn, nothing less than drastic action can dissuade them.
Other lawn munchers include a number of “worms” that are actually caterpillars of various moths and butterflies, such as armyworms. June bugs or other larvae (grubs) such as those of Japanese beetles, feed on root systems, causing irregular bare spots. Grubs can cause significant damage if their numbers get out of hand. Subsoil feeders can be differentiated from most fungal diseases in that the root system is simply gone and the grass can be pulled up in tufts with no sign of roots. Diseases will usually have mushy crowns or roots. Mites or chinchbugs can be a problem on some grass species in hot dry weather. Fire ants present special challenges and constant vigilance. Not only are their mounds unsightly, but they’re a real hazard to man and beast alike. Fire ant control strategies usually consist of a combination of chemicals to knock them back to acceptable levels. I fled fire ant country, but alas, they tracked me down to northwest Arkansas. Unfortunately, it takes chemical firepower to combat these insects in highly managed turf where appearance is paramount.
Mineral problems are usually chalked up to a nutritional or soil pH imbalance: either too much or too little of something. Poor water quality – high in salts – can also cause problems. A yearly soil test will prevent a lot of problems. Most turf species are tolerant of acid or alkaline soils, but a few, such as St. Augustinegrass will show micronutrient deficiencies on high pH alkaline soils while other turf species prefer high pH soils. Nitrogen is usually the limiting element in turf nutrition. To lessen the chance of nutrient runoff, it is best to feed the turf with small amounts of nitrogen over time: a slice of bread rather than the whole loaf. Soil testing reports advise what, how much, and when. And in Arkansas, soil testing is free. Contact your local cooperative extension agent for details. Other problems include elevated salt levels in the soil, which can burn root systems. The most common situation is when de-icing salts from sidewalks have accumulated over the winter. Sodium chloride (de-icing or table salt) is death to most plants. Calcium chloride, a de-icing alternative, doesn’t have the sodium component, but the chloride can be just as bad. Salts can also build up over time in soil in areas with poor water quality. Leaching with rainfall or high quality water is nearly the only long-term solution.
Other abiotic (non-living) factors that affect grass growth include summer drought or cold-weather damage on warm-season grasses during severe winters. Winterkill is common on warm-season grasses in the transition zone between the Gulf Coast and Mid-America, which includes most of Arkansas. Most grasses will recover, but sometimes repair seeding or plugging is needed for high-profile sites.
Vegetable in this case refers to not only weeds, but also pathogenic microorganisms that fall more into the realm of plants than animal or mineral (I can hear the plant pathologists screaming about that, but humor me here). Entire books have been written on the various diseases that affect turf species, so I can only give general advice. Like disease control on most plants, preventing is better than curing. Good air circulation, by reducing surface level humidity, can reduce the incidence of fungal infection by Rhizoctonia and Pythium organisms, which cause the majority of turf diseases. Avoid irrigating the grass late in the day, as free water on the leaves overnight creates prime conditions for infection. Sufficient sunlight should be present to maintain a healthy stand of grass. A thick layer of thatch (accumulated turf clippings) can hold excess moisture and generally provides an environment for diseases. The most common diseases on turf include brown patch, which affects cool-season grasses such as fescue and ryegrass in the early summer. Large patch, caused by the same organism, affects warm-season grasses, such as bermudagrass in the spring and fall when nighttime temperatures are cool. Pythium blight hits grasses in wet damp areas during the summer. All of these diseases manifest themselves as small to large circular spots where the grass loses its green coloring and turns brown. The turf species, time of year, and the size of the infected area will often determine which disease organism is causing the problems. It is important to identify the causal agent and not throw the entire chemical arsenal at the problem, as some diseases require specific treatments.
Weeds are legion, but usually can be effectively controlled by either pre-emergent or post-emergent herbicides – or good ol’ bending over and pulling them, which can be great anger management therapy. The worst offenders in this neck of the woods are dandelions, annual bluegrass, dallisgrass, and crabgrass. But please, be cautious when applying any herbicide, as many plants, apple trees for example, are extremely sensitive to pre-emergent herbicides. Read the label carefully to ensure the product can be used on your specific grass. Many a St. Augustinegrass lawn has been damaged by applying herbicides intended for bermudagrass. Caveat emptor!