Gray Leaf Spot: Should You Be Concerned?

grass

Gray Leaf Spot is beginning to show activity on St. Augustine lawns in the south and southeastern parts of the country. This is an important infectious disease and can also occur on cool-season grasses, Tall Fescue and Perennial Ryegrass, although it generally shows up on those grasses later in the summer.

This disease shows up on St. Augustine when the weather becomes hot and humid. It affects the turf by severely blighting and defoliating the leaves of the grass, but does not affect the roots. It is more of a problem on lawns that receive excessive amounts of nitrogen fertilizer during the summer months, so be careful about adding too much nitrogen to your lawn in the heat of the summer.

5 Contributing Factors:

  1. Soil compaction
  2. Improper irrigation practices
  3. Watering at night – the disease can spread rapidly when it has temperatures of 85° or higher.
  4. Humidity
  5. Time of the year: specifically, June through September

Characteristics:

On St. Augustine, symptoms of the disease include leaf spots with reddish brown borders. The center of the spot takes on a tan color and they may grow together to form large blighted areas. It gets its name from the gray fungal growth, that resembles gray velvet, which appears on these spots during wet, humid weather.

gray leaf spot

When the spots become numerous, the entire leaf may wither and die.  The turf will take on a blighted or scorched look. Some patches will develop more of the disease than other areas of the lawn. These spots can be confused with drought stress or even insect activity.

Treatments:

There are disease control treatments that can be applied if the disease is caught early. Once the grass blades start to die off, it becomes much harder to help the lawn recover. One thing to remember is that the grass blades that have the disease will need to drop off. New grass blades that grow in their place will have less or none of the disease symptoms present.

Sometimes customers ask about the amount of fertilizer that is applied to a lawn and ask whether it is causing the particular type of disease to occur. It is a very good question. Spring-Green’s lawn care programs are adapted to the type of turf grass that is being treated.

We have worked with university consultants, product manufacturers and industry experts to put together lawn and care programs that meet the needs of the turf and provide the results that our customers desire. It is never a good idea to try to supplement our programs by adding additional fertilizer on your own. We guarantee results for our full program customers. If you are unhappy with results, contact us and we will work with you to make it right or we will refund your money for that application.

Monitor your lawn for this serious disease. If you suspect your lawn has Gray Leaf Spot, contact your neighborhood lawn care professional at Spring-Green to check your lawn and they can advise you on treatment options.

Should You Be Seeding Your Lawn This Spring?

big lawn

Occasionally a customer will ask if they can seed their lawn in the spring. For those who live in the south, the grasses that grow in your area are usually not started from seed. Therefore this article is mainly directed at areas where cool-season grasses grow.

In most cases, seeding your lawn in the spring is not a good idea. The main reason for this is that weed control cannot be applied before or after the lawn is seeded. This is true for the pre-emergent weed control products that are designed to inhibit annual grassy weeds from germinating. Likewise, it will keep desired grass seed from germinating as well.

Sometimes a lawn is just in bad shape and needs help to get going again. If your lawn is thin and weedy, it is better to get the weeds under control. Try to increase the density of the grass that is growing by fertilizing it then try seeding it and hopefully your new grass will out-compete the stronger, more established weeds. Keep in mind that it is better to get weeds in check in summer and fertilize your lawn to get it healthy and then re-seed in late August to early September.

Choose a product that has a crabgrass preventer included with the granular fertilizer. Be sure to follow the directions on the label as to the amount of product to apply per 1,000 sq. ft. Determining the size of your lawn care can be difficult, but it can be done using a plat of survey. Be sure to make allowances for landscape beds, pool and decks or patios.

I suggest using a liquid weed control product to control the weeds in your lawn. Be sure to read and follow the directions before using the product. Also, make sure you choose a product that only controls broadleaf weeds, and not weeds and grasses.

Depending on the species of turf in your lawn, you should continue making applications of fertilizer throughout the summer. Bluegrass and perennial ryegrass should receive about 3 to 4 pounds of nitrogen per year whereas tall fescue should receive about 2 to 2.5 pounds of nitrogen per year. All of these grasses do better when higher amounts are applied in early spring and fall and less in the summer.

When late August rolls around, it is time to core aerate your lawn. After doing so, spread grass seed across your lawn after aerating. Here are the recommended amounts of grass seed to sow per 1,000 square feet:

After you have seeded, make another application of fertilizer at the ¾ pound N rate after seeding. Be sure to keep the new seed watered for 3 to 4 weeks. Make a late season fertilizer application in October through November, depending on where you live. But of course, the easiest way of caring for your lawn is to contact your local Spring-Green office.

Is Your Lawn Mower Turning Orange? You May Have Lawn Rust Problems

Orange color on shoes from lawn rust disease

My lawn was doing great. We enjoyed a wetter-than-normal summer and the temperatures have been warm, but not blazing hot. About three weeks ago, that all changed and we shifted into a normal hot and dry summer. If you live in the Midwest and your lawn has perennial ryegrass in it, you may have noticed your lawn mower turning orange after you mow your lawn. Your shoes also seem to have taken on an orange-ish sheen. This is all happening due to a common turf disease that has been aggravated into activity by a change in the weather—Lawn Rust.

Now, the first thing to know about Lawn Rust Disease is that the spores of this disease are already present in your lawn, as well as just about every other lawn in your neighborhood. The disease becomes active due to the environment, which lately is the perfect concoction for Lawn Rust to develop. Just like a fire needs three components to develop – fuel, heat and oxygen – diseases occur when three conditions are all present: pathogen, host plant and environment. Since those three were all present, Lawn Rust developed in the grass.

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The best way to tell if your lawn has Rust is to look at the individual grass blades. You can usually tell the areas where the disease is more prominent, since that area of your lawn will look slightly yellow. If you scuff your feet across the area, a cloud of orange dust will rise up from the lawn. Pick up a few of the grass blades and you will see orange colored spore sacks, called pustules, in parallel rows on the grass blade. Applying a disease control material at this time will have little to no effect on Lawn Rust, as the disease has run its course and is now producing “seeds.”

Treating Lawn Rust Disease is fairly simple, actually. The best thing to do if you lawn has Rust is to fertilize it to stimulate new growth, and provide it with about an inch of water per week. It is also a good idea to collect clippings for two or three weeks to reduce the number of spores that are left on the lawn. It may take a few weeks, but your lawn will look great again.

For more information about Lawn Rust Disease and ways you can keep your lawn healthy, contact your local Spring-Green professional.