Let’s talk about an issue Ive been seeing a lot of lately with all the heavy rains. A condition called Iron Chlorosis, where the grass blades start to become pale yellow to almost white in sever cases. It’s simply a lack of nutrients in the lawn, mainly iron, causing the pale appearance. Many people can confuse chlorosis with a Nitrogen deficiency. However a nitrogen deficiency will leave the blades a more solid yellow color rather than pale. But we will talk about that at a later time.
There are a few different reasons why a lawn can become chlorotic. The most common reason is over watering. Either from running the irrigation system too long, of from too heavy of a rainfall. The excess amount of water will cause the nutrients to wash out of the lawn. If this is the case, a fertilizer containing iron or a sprayable iron treatment can help correct this issue. Always be careful when applying iron products because they will stain non target areas. Check the irrigation system to make sure its not the cause or any treatment will be in vain.
Another common cause is high phosphorus levels in the soil. If the pH level of the soil is too high, it will cause a distortion in the nutrient uptake of the turf leading to this pale color. If this is the case applying a 21-0-0, which is Sulfate if Ammonia, will help balance the pH of the soil, and give the turn some extra nutrients. 5 pounds per 1,000 sq feet is the normal rate for this, but could require a few treatments to get the pH to drop where it needs to be. Make sure to test the pH between treatments to make sure you don’t send it too far the other direction. The pH level for St Augustine you should aim for is 6.5.
With this, and any other issues you have, I recommend seeking the help of a Lawn Care Professional. They will have the products and equipment to properly take care of any issues you may have. If you decide to do it yourself, always remember : THE LABEL IS THE LAW! Make sure to careful read the label of any product you use to make sure its the correct product, and that you apply is correctly. It is against the law to use products outside of the parameters stated on the label.
Lets talk about an issue common this time of year, Sod Webworms. Ive been getting a lot of service calls, and seeing them a lot on my normal services lately. A lot more than I have in past years. You can see them throughout the year given the right conditions, but you will see the most activity from July-August.
Sod webworms are the result of moths laying their eggs in the lawn. These eggs turn to larvae, then pupate in early summer when they begin feeding on the lawn. Many people will see moths in their lawn and automatically assume its Sod Webworms. Even though this could be a sign, its not a for sure thing. There are a lot of different types of moths out there laying eggs for things other than Sod Webworms that won’t damage the turf.
When inspecting an area of the lawn where Sod Webworms are present, you will see green fecal pellets called frass, pictured above. You will also see the worms, which have a green color, also pictured above. They get to be 1/2″ – 3/4″ long, so they are fairly easy to see when inspecting. One way to inspect and area would be to take a couple gallons of water and add dish soap to the area. This will disturb the worms sending them to the top to breathe.
The Sod Webworms, are chewing the grass blades, so it will be easy to see the damage, From afar it will look like an area of the grass was mowed lower than the rest. Looking closer you will be able to see the chew marks on the grass blades. The area will also start turning a little brown from the stress as well. Since its just the grass blades being affected, the damage area will grow back in after a few mowings once the Sod Webworms are gone.
Sod Webworms are pretty simple to control. There are many different insecticides that will take them out. My preferred insecticide is any with the ingredient Bifenthrin since it is useful in controlling many other types of insects as well. Because Sod Webworms eat at night, its best to treat for them late in the afternoon to ensure the product comes in contact with them. As always, remember, THE LABEL IS THE LAW. When using any products make sure to read the label to make sure the problem you are trying to treat is listed on there. I recommend contacting your local Lawn Care Professional to resolve any of your lawn or shrub issues. They will have to proper products and equipment, as well as knowledge, to effectively take care of any of your issues.