ure out a way to pull cores at least 4 or 5 times annually as well
as solid tine at least 6 times. Without closing fields! Right now
we only have a brief closure in July and the fields are in play
from March to November.
Additionally, I have been considering which way to best
change the soil physical properties to meet the new, higher
demand. Sand is certainly an option but takes a LOT of
product and a lot of time. It would take about 1,000 tons
of sand to sufficiently modify the rootzone of one soccer
field and we have seven. Not to mention football, lacrosse,
etc. The labor and cost add up to beyond our means. I am
looking at some of the Turface, Zeolite, Axis products as an
alternative. No decisions yet.
The second concern is using growth regulators more
effectively. Labor is always the limiting factor in a municipal
setting (as far as I can tell) and mowing 40 acres of sports
fields three times weekly severely inhibits our ability to meet
other responsibilities. Without growth regulators, I cannot
drop to twice weekly mowing without suffering through grass
clipping problems. So, we use growth regulators every 14 days
to help keep labor free as well as all the other benefits they
provide for turf.
Due to constant seeding of highly used sports fields,
conventional wisdom says not to use Class B PGR's (late GA
inhibitors) like Cutless and Trimmit because of their root
uptake and poa annua killing properties when used on the
label recommended program. Only Class A PGR's (early GA
inhibitors) like Primo are prevalent on sports fields for a con-
tinuous program of growth suppression. The problem with
Primo alone is that it has a life span of only 5-7 days in the
heat of the summer.
Back to the labor issue: it is not practical for us to spray
more than every 14 days. So, through experimentation with
a combination of Class A and low continuous rates of Class
B PGR's tank-mixed, we were able to achieve fairly consistent
suppression on a 14-day spray schedule WITHOUT damag-
ing poa or impeding seed germination throughout 2015. But
only on fields that are predominantly perennial ryegrass or
predominantly Kentucky bluegrass. Fields with a patchwork
of the two grass types did not fare well as the KBG takes much
lower rates to suppress than the perennial ryegrass. So, 2016
will be dedicated to fine-tuning the rates and products to
achieve ideal suppression that allows twice weekly mowing as
well as aesthetically pleasing turf. ■
ST
www.stma.org January 2016 | SportsTurf 39
Without growth regulators,
I cannot drop to twice weekly
mowing without suffering through
grass clipping problems.
— Rebecca Auchter
