By Bob Dailey
Fungal problems are a fact of life in Southeast Texas, where fungus is the main disease vector in plants. Actually, most soils here are full of fungal spores. Some are beneficial. Some, harmless. And some, like the fungi that cause take-all patch, brown spot or dollar spot, are problematic. Given the right circumstances, unwanted fungus can explode into a serious situation.
The most common “right circumstances” are:
Improper mowing, specifically mowing too low. The leaves of any plant are how it makes food. Crew-cutting lawns takes away most of the food-producing grass blades, allows the ground to dry out, and allows too much heat (or cold) to penetrate into the soil, killing beneficial organisms.
Solution: set your lawn mower to the highest mowing level, or ask your lawn service to do it.
Soil begins to compact when deprived of organic material, micro-organisms, earthworms and other beneficial organisms. Compacted soil exists throughout The Woodlands. Solution: Synthetic fertilizers, pesticides and fertilizers disrupt the soil’s ecosystem, and kill the organisms necessary for good soil.
Solution: Apply organic material at least twice a year (mid-April and mid-October are the best times). Spread it about 1/2 to 3/4 inch deep and rake it in with a leaf rake. Use a mulching lawnmower. Since most of the grass’s nutrients are in its blades, mulching it back into the soil re-introduces nitrogen, and other materials into the soil. Finally, if not planning to compost leaves, mulch them into the lawn as well.
Too much fertilizer can cause fungal diseases to activate. It can also kill beneficial organisms. Too much fertilizer will green up a lawn quickly, but will not protect it from fungus.
Solution: Use an organic, slow-release fertilizer on your lawn. And avoid using too much. Follow the instructions on the package exactly.
Watering lawns every day, or giving a lawn more than an inch of water per week is a sure way to encourage fungal diseases.
Solution: For in-ground sprinkler users, put a rain gauge in each zone (or move it around). If each zone measures an inch, then the irrigation system is set correctly. If the lawn receives more than an inch, reset the controller. It may seem counterintuitive, but using an inch of water (or less if it rains) will actually create a deeper root system and stronger, more disease resistant plants. Woodlands Water offers a rebate of 50% on the purchase and installation of water saving devices, such as rain sensors and ET controllers (with a cap of $150).