Plant Diseases in Arkansas
Dollar Spot
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Audio/Video Script:
Dr. Steve Vann
Extension Urban Plant Pathologist
Dollar Spot is a very common disease of turfgrasses that we see every year
virtually, and especially this time of year when temperatures get quite a bit
warmer than normal.
This disease is actually caused by a fungus that attacks
most all of our turfgrass species that grow here in Arkansas. However, we
primarily see it on Bermuda & zoysia grasses.
Now this disease is actually
caused by a fungus that will attack the above ground parts of the plant. The
typical symptoms that we see for the homeowner are going to be small dead
patches usually two or three inches in diameter that occur out in the lawn
during these hot dry periods of time during the summer time. We usually
don’t see this disease, in other words it’s not very obvious until several of
these patches actually grow together, then we see large areas of the lawn
that appear to be browning out.
One of the diagnostic characteristics for this
disease is that homeowners can actually go out in their lawn first thing in the
morning and examine these dead areas, and actually see a white fuzz that
resembles cobwebs growing on those dead areas. That’s very diagnostic for
Dollar Spot.
Closer examination of those individual plants of your turf shows a
very characteristic banding of light and darker bands of color. Again this is
very diagnostic for Dollar Spot.
This disease is oftentimes associated with turfgrasses that are poorly maintained. In other words, turfgrasses that may be
running out of fertilizer or appropriate water in the soil, so this is one of
the reasons we see it in the summertime.
So it’s one of these diseases that we
call a stress related disease. So one of the best ways to manage this disease is
to make sure that your turfgrass is being irrigated properly, number 1, and it’s
being fertilized correctly.
Fertilizer or fertilization practices are going
to need to be based on a recent soil test. That’s the best way to make sure that
your turf is getting the appropriate amount of fertility.
As far as irrigation
practices go, it’s always a good idea to irrigate your yard early in the
morning. Primarily between the hours of four a.m and eight a.m. This reduces
the chances of other turf diseases getting started and allows that grass to dry
out by at least mid to late morning. So it’s always a good idea to do this.
So
this particular disease can be managed by good fertility, good soil moisture.
It’s also a good idea to maintain the appropriate cutting height of your
individual grass. We have fact sheets available on our website that will
give you the appropriate cutting height. Because if we tend to cut our grasses
too short, this may make them susceptible to a lot of infectious diseases. So
it’s real important.
There are several chemicals that can be used to control
this particular disease. Those that contain the active ingredient of propaconazol, mycabutanil or tridemafon are effective for this disease. One of
the options for a homeowner may include the fungicide called fertalome liquid
systemic fungicide, is labeled for this particular disease. Also another
homeowner product is called inninox and it’s effective for Dollar Spot as well.
Announcer:
To learn more, contact your county extension agent and follow the links in this
section.
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