By Bill Lamson-Scribner
With all of the heavy rains, Large Patch/Brown Patch is
really giving our Lowcountry grasses a hard time! The cooler nights, lower daylight hours, and
these rains have created an environment favorable for the spread of this
disease. Hopefully, you are all saving
some money and have turned off your irrigation.
If you have discolored grass this time of year, it could be Large
Patch, or I am still seeing plenty of worm (fall army worm, sod web worm)
activity. You must identify what pest
you have because worms are an insect which needs insecticides and Large Patch
is a fungus which requires a fungicide to eradicate.
Where you have Large Patch, there is a dead area in the
center that is outlined by yellow grass.
If you pull on the dead grass or the yellow grass, it will come up very
easily from the runner. At the bottom of
the leaf blade you just pulled up, you will see a dark discolored area. Large Patch is a soil borne fungus that
attacks the grass at the crown of the plant.
The crown of the plant is the areas where the leaf blades go up and the
roots go down. In the dead area, you can
rake up the dead blades of grass with your fingers.
If worms are munching on your turf, the discolored areas
will have half eaten leaf blades. If you
see an area in your lawn that looks like it has been mowed, but you haven’t
mowed in awhile, that could be an area where worms have been feeding. You can also see the worms or their fecal
pellets in the bad grass that borders the good grass.
Moths are very evident in lawns that have worms. If you walk
around your yard at dusk and see moths fly up out of your lawn, there is a very
good chance you have worms on the way. Moths lay eggs. The eggs turn into the
worm that eats your grass. The worms then turn into moths and the cycle
continues. Moths will also hang out in flower beds. They especially seem to
like Liriope (monkey grass).
Large Patch reappears in the same place every year which
makes it easy to control. Large Patch
likes compacted, thatchy, wet and poorly drained areas. Large Patch also likes yards where people run
irrigation all the time regardless of rain.
If you can manage these cultural issues through aeration, de-thatching
and correcting drainage, you should notice a decrease of the fungus in your
yard.
Serenade is an organic fungicide that you can use to control
Large Patch. Applying Natures Blend,
Crab Shell and SeaHume in these areas will increase the bio-diversity and
relieve compaction. Many of our
customers have noticed a great reduction in Large Patch in the areas where they
applied Natures Blend, Crab Shell and SeaHume.
Cleary’s and Disarm products systemically move into the plants and
protect them from disease.
For fungi it is best to treat before your grass gets the
disease. Like the way people get a flu shot, before they get the flu.
Fungicides will help afterwards to prevent further damage; however, the dead
grass will not come back to life.
Sevin is a great product to control worms. Not only will it kill the worms, but it will
also kill other things in the soil that moles feed on. Bifen or Bug Blaster
will work too. If you would rather go organic, Thuricide is a Bt product that
will help kill the worms. Applications
every 2 weeks is not uncommon.
Always read, understand and follow
product label. The product label is a Federal Law.
