Yesterday I attended a workshop at O.S.U. in Stillwater on Winterkill of
Bermudagrass and Spring Dead Spot. Both are big issues now on bermudagrass
lawns, so the turfgrass department gave us the latest information on both.
Part of the challenges of growing bermudagrass was evident while we were
there, wearing jackets in mid-May due to the temperatures in the 40’s.
Bermudgrass just won’t do much until temperatures get into the 80’s
and 90’s consistently, with nighttime temperatures at least in the
60’s. That’s not been the case this spring, which is the reason
I’ve only had to mow my bermuda lawn once this year so far.
Although it was a long, cold winter, Dr. Martin from O.S.U. stated that
while we’ve had some winterkill, it’s fairly spotty. The bermudagrass
is just having a hard time getting going with the cool weather, and in
some cases the lack of adequate soil moisture. They did visit about the
fact that some varieties of bermudagrass are more susceptible to winterkill
than others, hence the fact that some lawns are affected and some look
just fine. There are many varieties of bermudagrass, and many genetic
differences within certain varieties, such as U3 Common. So just as people
do not all look and perform alike due to genetics, the same is true of grass.
Spring Dead Spot is a fungus disease, again more common on certain varieties
of bermudagrass. That’s why some lawns will have it, and others
will not. While soil fertility, weather, drainage, and turf age are all
factors, genetics is the major factor in disease incidence. One study
that O.S.U. did recently showed that ending nitrogen fertilization on
bermudagrass by mid-September decreased the severity of the disease. That’s
exactly what we do at LawnAmerica, with our final “fall fertilizer”
for bermudagrass applied in August into early September. So while we can
make a lawn dark green and lush with fertilization in late September and
early October, that’s not what we want to prevent Spring Dead Spot
from taking over a lawn. Fertilizing with nitrogen too late in the growing
season also hurts the root system, which makes the grass more prone to
winterkill. So we try to run the turf a little on the lean side as we
go into fall as far as nitrogen and color is concerned.
Even if we do all the right things though, Spring Dead Spot can still come
in and be a factor. In severe cases, O.S.U. recommends two fungicide treatments
in fall, when the Test showing influence of fertility on Spring Dead Spotfungus
is active, to prevent the disease from being severe the following spring.
We can provide that at LawnAmerica with our Spring Dead Spot Fungicide
Treatment, and it does seem to show some decent success. It’s not
perfect, but one can expect to see fewer dead spots the following spring,
and they will fill in faster with healthy bermudagrass. We apply one treatment
in early September, and followup with another 30 days later. The fungicide
does need to be watered into the soil for best results after treatment.
Fungicides are not cheap, so our fee is 2.1X your normal lawn treatment
cost to cover both treatments.