the Fate of Field Paspalum Control - The Paginator

stocks on golf courses after December
31, 2013, will be prohibited. The EPA
also has restricted the use of MSMA
to spot applications, and other restrictions
apply (U.S. EPA, 2009).
MSMA and DSMA were the only
known effective and selective herbicides
for use on many cool-season
grasses for control of dallisgrass, field
paspalum and other Paspalum spp.
Hence, new herbicides need to be
identified for controlling these turfinvading
Paspalum spp.
Our research
The search for alternative herbicides
for control of field paspalum began
at the University of Maryland Paint
Branch Turfgrass Research Facility
in College Park in 2009. We conducted
three separate field studies in
2009 and 2010. In 2009, we assessed
Fusilade II T&O (fluazifop-P), Segment
(sethoxydim) and Round-up
(gylphosate) in an unimproved site of
perennial ryegrass and Kentucky bluegrass.
In 2010, we evaluated Fusilade
II, Velocity (bispyribac-sodium),
Dismiss (sulfentrazone) and Certainty
(sulfosulfuron) in a mature stand of
tall fescue (Festuca arundinacea).
Also in 2010, we assessed Tenacity
(mesotrione) and Tupersan (siduron)
as preemergence treatments in springseeded
stands of tall fescue, hard
fescue (F. brevipilia) and perennial
ryegrass (Lolium perenne).
In both 2010 studies, the herbicide
treatments were applied for purposes
other than targeting field paspalum.
Once some level of field paspalum
control became evident in the 2010
sites, however, data were collected
despite paspalum not being the
main target.
Herbicides were applied in 50 gallons
of water per acre using a CO2
powered (35 psi) backpack sprayer
Photo 1. Field paspalum is a warm-season perennial bunchgrass.
Photo 2. Field paspalum on a bentgrass tee.
Summary of Key Findings
• Fusilade II appears to be an alternative
to MSMA for postemergence
control of field paspalum
in tall fescue turf.
• Fusilade II also is known to be
safe to use in hard fescue, but
more research needs to confirm
if other turfgrass species are
tolerant of the herbicide.
• More research is needed to identify
effective Fusilade II label use
rates and timings. The Fusilade II
label would have to be amended
to include Paspalum spp.
• Postemergence applications of
Certainty, Dismiss and Velocity
alone were ineffective in controlling
field paspalum, but a tank
mix of Velocity + Dismiss showed
some promise.
• Preemergence applications of
Tenacity and Tupersan to spring
seedbeds provided significant
reductions of field paspalum
development from seed, but
many plants did escape.
• Certainty was extremely phototoxic
to tall fescue and is labeled
for selective tall fescue control
in Kentucky bluegrass turf.
SUMMER 2011
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