Patricia M. Arledge, Sharpe, Kenneth W.
News Article for November 16, 2015:
I am surprised at how lawns are still growing this late into the season. With unusually warm weather and more than adequate moisture grass is still very green and actively growing.
Another consequence of this moderate temperature that I have noticed is the disease brown patch actively growing in St. Augustine grass in the courthouse lawn this past week. Brown patch can be very active in the fall when temperatures moderate and you have moist conditions. It will show up as a yellow or orange colored circle that will expand. You might consider a fungicide treatment to stop brown patch from spreading now. Most treatments will require 3 applications timed 10 days apart. I would spray the infected area plus a few feet of buffer. Recommended fungicides would include Fertilome F Stop, Green Light Fung-Away, Spectricide Immunox, Bayer Advance Fungus Control for Lawns and Bonide Infuse Systemic Disease Control for Lawns.
For those who would like to have a green lawn all winter long I would go ahead and start planting ryegrass now. There are two types of ryegrass that you can use, annual ryegrass or perennial ryegrass. Annual ryegrass is commonly used in pastures and food plots but can be used in lawns. It tends to grow taller and have a wider leaf than perennial but you will have to mow the ryegrass so that is not an issue.
Perennial ryegrass will not come back next year as the name perennial would imply. It is however more attractive because it is finer textured and shorter growing. Perennial ryegrass is used to over seed athletic fields and golf courses and is usually more expensive.
Prior to seeding ryegrass cut your lawn a little shorter than normal, but do not scalp the grass. The shorter grass will allow the seed to more easily reach the soil.
We use a much higher rate of seeding for lawns than we do in pastures because we will continue to mow the grass and it needs to be thick enough to give good coverage at a mowing height of about 2 inches. Over seed ryegrass at a rate of 8-10 pounds per 1000 ft².
Spread the seed evenly over the lawn. I have found that that it easier if you will spread half of the seed in one direction (north and south) and then spread the other half coming across (east and west). Next, either rake or drag the lawn to shake the seed down to the soil and then apply water.
Once the ryegrass seed emerge in a few weeks fertilize with a completer fertilizer such as 13-13-13 or the equivalent at a rate of 6-7 pounds per 1000 ft² and water the fertilizer in.
For area livestock producers the warmer weather has produced an unusual late season infestation of fall armyworms in ryegrass. I have seen damage all over Livingston parish over the past few days. Armyworms are caterpillars that have a ferocious appetite and like well fertilized grasses like ryegrass.
If you think your ryegrass stand looks spotty and you were assuming it was due to all of the rain, go take a good look. I have seen damage ranging from 50-80%. The economic threshold for spraying is usually considered to be 1 to 2 armyworms per square foot.
If small ryegrass seedlings are completely defoliated by armyworms feeding, it may be necessary to do some reseeding. Plants that have a few inches of leaf tissue remaining will usually regrow.