Document ID: EPA-HQ-OPP-2006-0201-0027
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2006-04-20T04:00Z

UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON
D.
C.,
20460
April
12,
2006
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
MEMORANDUM
SUBJECT:
Alternatives
Assessment
of
the
Organic
Arsenical
Herbicides
Used
in
Residential
and
Golf
Course
Turfgrass,
and
Cotton
(
DP
Barcode:
309117)

FROM:
William
Phillips,
II,
Ph.
D.,
Agronomist
Biological
Analysis
Branch
Derek
Berwald,
Ph.
D.,
Economist
Elisa
Rim,
Economist
Economic
Analysis
Branch
Biological
and
Economic
Analysis
Division
(
7503C)

THRU:
Arnet
Jones,
Chief
Biological
Analysis
Branch
Timothy
Kiely,
Acting
Chief
Economic
Analysis
Branch
Biological
and
Economic
Analysis
Division
(
7503C)

TO:
Lance
Wormell,
Chemical
Review
Manager
Special
Review
and
Reregistration
Division
PRODUCT
REVIEW
PANEL:
April
5,
2006
SUMMARY
As
part
of
the
re­
registration
eligibility
decision
(
RED)
of
the
organic
arsenic
(
OA)
herbicides,
BEAD
is
providing
an
assessment
of
alternative
herbicides
for
the
major
use
sites.
Based
on
the
available
data,
cotton
and
turfgrass
(
homeowner
and
golf
course)
are
the
major
use
sites,
comprising
greater
than
80
percent
of
the
use
of
the
OA
herbicides
CAMA
(
calcium
methanearsonate),
DSMA
disodium
methanearsonate),
MSMA
monosodium
methanearsonate),
and
cacodylic
acid
(
hydroxydimethylarsine
oxide).
2
Many
turf
grasses
are
tolerant
to
the
OA
herbicides
CAMA,
DSMA,
and
MSMA,
and
the
OA
herbicides
offer
effective
control
of
several
difficult
to
control
grass
species
and
several
broadleaf
weed
(
BLW)
species.
In
addition,
cacodylic
acid
can
be
used
as
a
selective
weed
control
in
bermudagrass
(
Cynodon
spp.)
turf
and
is
often
formulated
with
MSMA
to
broaden
the
control
spectrum.
In
agronomic
production,
DSMA
and
MSMA
are
used
as
postemergence
control
in
cotton,
and
cacodylic
acid
is
used
as
a
pre­
plant
burn
down
weed
control
and
as
a
cotton
harvest
aid.

The
use
of
the
OA
herbicides
in
homeowner
turfgrass
is
primarily
for
postemergence
control
of
the
annual
grass
weeds
Large
and
Smooth
Crabgrass
(
Digitaria
ischamum
and/
or
sanguinalis).
These
products
are
sold
as
a
concentrated
liquid
to
be
broadcast
applied
through
a
hose­
end
sprayer
(
HES),
or
as
a
spot
spray
from
a
pre­
diluted
ready­
to­
use
(
RTU)
spray
bottle.
Most
often
these
products
are
a
mix
of
several
postemergence
herbicides
chosen
to
broaden
the
weed
spectrum
of
the
respective
products.
Currently,
the
only
herbicides
available
to
homeowners
for
the
postemergence
control
of
grass
weeds
in
turfgrass
are
CAMA,
DSMA,
and
MSMA,
as
well
as
fluazifop
and
dithiopyr.
Without
the
availability
of
the
OA
herbicides,
homeowners
would
need
to
rely
primarily
on
fluazifop
and
dithiopyr
for
postemergence
control
or
apply
preemergence
(
e.
g.,
dithiopyr,
pendimethlin)
crabgrass
weed
control.
Preemergence
active
ingredients
(
ai)
are
very
efficacious
at
controlling
crabgrass
seedlings.
Given
that
crabgrass
germinates
at
soil
temperatures
greater
than
50
º
F,
continued
education
of
the
public
to
the
earlier
application
timing
of
these
preemergence
herbicides
will
remain
important;
these
herbicides
require
application
prior
to
the
beginning
of
routine
homeowner
spring
turfgrass
maintenance.
BEAD
has
provided
a
table
that
contains
alternatives
currently
available
to
homeowners
for
specific
weed
control
within
each
turf
species
supported
by
the
registrant
(
Table
1).

Weed
control
in
golf
course
turfgrass
maintenance
has
many
competing
products
both
post­
and
preemergence.
Specifically,
for
grass
weed
control
in
golf
course
turfgrass
there
are
several
competing
herbicide
ai.
However,
these
alternative
herbicides
either
have
a
narrow
spectrum
of
weeds
that
they
control,
or
they
do
not
control
the
more
difficult
grass
weeds
like
dallisgrass
(
Paspalum
dilatatum)
(
Elmore
et
al.,
2003).
By
contrast,
the
OA
herbicides
have
a
broad­
spectrum
of
grass
weed
control,
which
includes
several
of
the
more
difficult
to
control
grass
weeds.
Due
to
this
broad
spectrum,
and
species,
of
weeds
controlled
by
the
OA
herbicides,
it
requires
that
several
herbicides
be
listed
as
alternatives
in
order
to
achieve
comparable
weed
control.
This
broad­
spectrum
weed
control
presents
a
unique
challenge
when
determining
alternatives,
as
there
is
no
herbicide
that
can
be
considered
a
direct
replacement
for
the
OA's.
As
a
best
case
scenario,
BEAD
has
developed
alternatives
herbicide
treatments
using
two
to
three
herbicides;
the
number
of
herbicides
is
dependant
upon
the
turf
specified
(
Table
2).

In
cotton,
the
predominant
uses
of
the
OA
herbicides
are
as
postemergence
applications
for
many
difficult
to
control
weeds.
Cacodylic
acid
is
a
pre­
plant
burn
down
herbicide,
and
it
is
often
used
as
a
desiccant
to
aid
harvest.
OA
use
in
cotton
has
been
declining
since
the
mid
1990'
s
(
USDA
NASS
Pest
Management
Database).
This
decline
has
been
fueled
by
the
increase
in
the
planting
of
the
transgenic
glyphosate­
tolerant
cotton
varieties.
The
use
of
the
OA
herbicides
in
cotton
production
has
consistently
decreased
since
1995.
Cacodylic
acid
use
as
a
desiccant
has
also
decreased
in
use
since
1997
(
USDA
NASS
Pest
Management
Database
).
Cotton
alternative
herbicides
are
in
Table
4,
and
their
associated
costs
can
be
found
in
Table
7.
Also,
lists
of
cotton
defoliants/
desiccants/
boll
ripeners
are
included
in
Table
5.
The
alternative
herbicides
are
typically
more
expensive
than
the
organic
arsenicals.
In
addition,
because
in
many
cases
one
treatment
of
organic
arsenicals
must
be
replaced
with
3
multiple
different
alternatives,
the
additional
cost
to
the
grower
can
be
significant.
The
financial
impacts
of
alternatives
vary
from
a
savings
of
about
a
dollar
for
Diuron
to
an
additional
cost
of
$
13
per
acre
for
pyrithiobac­
sodium.
We
provide
an
example
calculation,
using
a
representative
situation
in
Mississippi,
that
shows
the
alternatives
to
be
about
$
11
per
acre
more
expensive
that
the
organic
arsenical
MSMA.
This
results
in
a
decrease
in
net
revenues
from
cotton
sales
over
direct
costs
of
about
48
percent.
When
we
include
government
payments
to
growers,
the
increased
costs
of
organic
arsenical
alternatives
reduces
grower's
net
revenues
by
about
5.8
percent.

Within
the
scope
of
the
major
uses,
the
alternative
herbicides
for
the
OA
herbicides
range
from
numerous
to
none
at
all.
There
exist
a
number
of
alternative
herbicides
for
both
turfgrass
markets;
however,
the
alternatives
picture
for
cotton
is
not
a
clearly
defined.
When
determining
alternatives
for
herbicides
several
factors
were
considered,
and
among
them
were
efficacy,
crop
selectivity,
and
weed
spectrum.
Within
this
assessment,
every
effort
has
been
made
to
include
relevant
alternatives
based
on
university
recommendations
as
well
as
other
credible
sources.

BEAD
believes
that
there
is
a
trend
in
herbicide
usage
away
from
the
organic
arsenicals
and
toward
glyphosate.
Due
to
the
development
of
glyphosate
resistant
weed
biotypes,
this
decreasing
use
trend
has
probably
reached
a
minimum
and
perhaps
may
begin
to
show
future
signs
of
increasing.
BEAD
advises
caution
in
the
increased
reliance
on
a
small
group
of
herbicides,
or
herbicide
families,
as
problems
such
as
resistance
and
environmental
loading
have
the
potential
of
becoming
issues.

TURFGRASS
There
are
three
methods
for
homeowners
to
maintain
lawns
free
of
grass
weeds
such
as
crabgrass.
The
easiest
way
to
accomplish
this
is
to
use
cultural
practices
that
help
to
maintain
a
thick,
well­
groomed,
lawn.
As
most
grass
weeds
require
sunlight
to
germinate,
the
establishment
and
maintenance
of
a
healthy
lawn
is
the
best
method
to
have
a
crabgrass
free
lawn
(
Dernoeden,
1996).

The
second
way
to
maintain
a
lawn
free
of
troublesome
grass
weeds,
and
broadleaf
weeds,
is
to
apply
preemergence
herbicides
in
the
early
spring
prior
to
the
soil
reaching
~
50­
55oF
for
a
period
of
seven
to
ten
days.
While
this
method
of
crabgrass
control
is
simple
and
long
lasting,
it
often
is
not
used
due
to
the
timing
of
application.
Crabgrass
begins
to
germinate
early
when
the
soil
surface
begins
to
warm.
This
means
that
in
many
temperate
climates,
applications
need
to
be
made
prior
to
landscape
green­
up.
This
timing
is
usually
far
too
soon
for
most
homeowners
to
entertain
working
in
the
landscape,
however
for
professional
lawn
maintenance
personnel
this
type
of
work
is
routine.
As
a
result,
most
homeowners
do
not
think
of
crabgrass
herbicide
applications
until
they
see
crabgrass
growing
in
the
lawn.
At
this
time,
only
a
postemergence
herbicide
will
work.

The
last
method
of
crabgrass
control
is
the
use
of
postemergence
herbicide
applications,
which
include
the
organic
arsenicals.
The
primary
selective
postemergence
OA
herbicides
applied
by
the
homeowner
are
either
MSMA
or
the
calcium
salt
formulation
of
the
OA
MSMA
called
CALAR,
CMA
or
CAMA.
The
Ca
formulation
was
developed
for
the
enhanced
tolerance
of
turf
grasses
over
either
of
the
sodium
salt
formulations.
The
most
common
form
of
the
OA
herbicides
used
in
professional
turfgrass
maintenance
is
MSMA.
4
To
obtain
single
application
control
of
a
difficult
weed
species
such
as
crabgrass,
the
OA
herbicides
must
be
used
immediately
following
germination.
Once
established
crabgrass
control
is
difficult
to
achieve
with
a
single
application
of
a
postemergence
OA
herbicide;
as
a
result
multiple
applications
must
be
made
throughout
the
spring
and
summer.
Without
the
use
of
a
preemergence
herbicide,
multiple
applications
of
the
OA
will
be
required
every
10­
14
days
throughout
the
spring
and
early
summer
for
crabgrass
control.

In
addition
to
crabgrass
control,
cacodylic
acid
is
available
as
a
total
vegetation
killer/
lawn
edger.
When
sold
to
homeowners,
products
like
Liquid
Edger
®
provide
an
alternative
to
other
total
vegetation
herbicides
for
use
in
lawn
renovation
as
well
as
vegetation
removal
around
driveways
and
parking
areas.
In
general,
homeowners
and
professional
golf
course
groundskeepers
tend
to
use
one
of
the
glyphosate
herbicide
products
for
nonselective
weed
control.

The
subject
of
co­
occurrence
of
OA
herbicides
is
significant
in
two
ways
that
are
based
on
geographic
regions.
First,
in
the
temperate
regions,
it
is
conceivable
that
an
application
of
either
CAMA
or
MSMA
could
be
made
to
a
turf
with
a
concomitant
application
of
cacodylic
acid
as
an
to
the
edges
of
the
turf,
or
as
spot
sprays
for
difficult
to
control
weeds
within
the
turf.
This
would
limit
the
cooccurrence
of
the
OA
herbicides
in
homeowner
lawns.
However,
in
the
warmer
regions
of
the
country
co­
occurrences
would
occur
due
to
package
mixtures
of
products
for
weed
control
in
a
bermudagrass
turf.
These
package
mixtures
include
products
such
as
ferti°
lome
Bermuda
Grass
Weeder
®
.
These
premixed
products
are
for
applications
to
lawns
for
the
selective
control
of
grass
and
BLW
in
bermudagrass.
Ferti°
lome
Bermuda
Grass
Weeder
®
contains
a
mixture
of
cacodylic
acid
and
MSMA.

HOMEOWNER
/
RESIDENTIAL
USES
Homeowner
turf
weed
control
is
most
often
centered
on
crabgrass
control.
This
focus
on
crabgrass
weed
control
is
a
result
of
the
off
color,
rapid
germination,
emergence,
and
growth,
as
well
as
its
aggressive
sprawling
growth
habit.
The
numerous
products
and
their
marketing
have
made
crabgrass
herbicides
very
popular
with
homeowners
wanting
a
picture­
perfect
lawn.
In
current
years,
the
most
common
herbicides
for
the
control
of
crabgrass
weeds
have
become
those
that
are
applied
pre­
weed
emergence
and
are
sometimes
packages
in
weed­
n­
feed
products.
However,
these
products
can
often
be
applied
too
late
in
the
season
requiring
a
follow­
up
application
of
a
postemergence
herbicide.

ALTERNATIVES
The
homeowner
market
for
turfgrass
weed
control
is
composed
of
many
herbicide
and
weed­
nfeed
products.
The
use
of
OA
herbicides
in
homeowner
turfgrass
is
primarily
for
postemergence
control
of
crabgrass
species
through
the
application
of
concentrated
liquid
in
a
hose­
end
sprayer
(
HES)
or
ready­
to­
use
(
RTU)
spray
bottles.
Still,
there
are
several
products
to
control
grass
weeds
in
turfgrass,
however,
these
products
contain
only
one
of
a
few
active
ingredients.
Preemergence
grass
weed
control
herbicides
for
use
in
turfgrass
will
predominantly
contain
one
of
the
two
ai
dithiopyr
or
pendimethalin.
In
addition
dithiopyr
can
offer
postemergence
control
of
very
small
crabgrass
(>
4
leaf
growth
stage)
(
Dernoden
1999).
Herbicide
products
available
to
the
homeowner
for
postemergence
control
of
grasses
in
a
turfgrass
contain
MSMA/
CAMA,
dithiopyr
and
fluazifop
(
Table
1).

Products
to
control
broadleaf
weeds
in
a
turfgrass
are
numerous,
but
the
number
of
ai
are
somewhat
limited.
However,
these
ai
are
not
as
limited
as
those
for
grass
control
(
Table
1).
The
ai
for
5
broadleaf
weed
control
represents
herbicides
from
a
few
chemical
families,
which
reduces
the
selection
for
resistant
species.
The
relative
importance
of
the
OA
herbicides
for
broadleaf
weed
control
by
homeowners
is
of
low
importance.

In
general,
alternatives
to
MSMA/
CAMA
that
are
available
in
the
homeowner
applied
turfgrass
market
consist
technically
of
only
two
postemergence
controls
for
crabgrass.
First
there
is
fluazifop
for
grass
control
in
tall
fescue
or
zoysia
turf.
Next,
for
all
other
species
of
turfgrass1
dithiopyr
is
the
only
postemergence
option
as
long
as
the
plants
are
treated
very
early
(
Table
1).
Given
the
restriction
of
weed
size
for
the
postemergence
use
of
dithiopyr,
practically
speaking
there
would
be
no
other
postemergence
grass
weed
herbicide
with
the
exceptions
of
those
herbicides
listed
for
tall
fescue
and
zoysiagrass.
Given
this,
the
role
of
preemergence
herbicides
would
become
more
important.
This
new
emphasis
placed
on
preemergence
herbicides
will
require
continued
education
regarding
the
narrow
window
for
treatment
timings.
In
addition,
the
ongoing
education
by
universities
and
others
regarding
the
maintenance
of
a
healthy
turf
will
remain
important.

While
the
OA
herbicides
are
not
primarily
applied
to
control
BLW,
their
weed
spectrum
does
include
several
BLW
species.
As
for
alternative
broadleaf
weed
control
in
residential
turf,
there
already
exists
in
the
market
place
a
few
herbicide
ai
(
2,4­
D
and
atrazine)
that
are
formulated
as
sprays
or
as
one
of
many
weed­
n­
feed
products.

1
There
are
label
restrictions
as
to
which
cultivars
may
not
be
tolerant.
6
Table
1.
Examples
of
Homeowner
Available
Preemergence
Herbicides.
Alternative
Herbicides
Active
Ingredient
Examples
of
Available
Products
Product
Active
Ingredient
Concentration(

s)
Application
Intervals
(

Days)
Applications
Year­

1
Formulated
Product
Rate
Pests
Grass
Weeds
Broadleaf
Weeds
Cacodylic
Acid
+

MSMA
Ferti°
lome
Bermuda
Grass
Weeder
®
1
33.97%

+
9.1%
7
­
14
NA
2
oz.

/
1000
ft2
Selective
Herbicide
for
Grasses
and
Broadleaf
Weeds
in
Bermudagrass
Turf
dithiopyr,
pendimethalin
(
Premergence)

dithiopyr
(
Very
Early
Postemergence)
2,4­
D,
dicamba,

triclopyr
(
Postemergence)

Cacodylic
Acid
(
Sodium
cacodylate
+

Dimethylarsenic
acid)
Liquid
Edger
®
2
0.09%
+

0.53%
NA
25
1
gallon
/
300
ft2
Most
Vegetation
diquat,
glufosinate,

glyphosate
diquat,
glufosinate,

glyphosate
CAMA
Ortho
Weed
B
Gone
®
Concentrate3
8.4%
7
NA
1gallon
/
6,800
ft2
Grasses,

BLW&
Nutsedge
Atrazine
(
St.
Augustine
and
Zoysia
only)

dithiopyr,
pendimethalin
(
Premergence)

dithiopyr
(
Very
Early
Postemergence)

fluazifop
(
Postemergence)
atrazine
(
St.
Augustine
and
Zoysia
only)

2,4­
D,
dicamba,
MCPA,

MCPP,
propanoic
acid
,

triclopyr
(
Postemergence)

MSMA
All­
in­
One
Weed
Killer
for
Lawns
®
Concentrate4
9.81%
14
2
1
gallon
/
42,668
ft2
Grasses,

BLW&
Nutsedge
atrazine
(
St.
Augustine
and
Zoysia
only)

dithiopyr,
pendimethalin
(
Premergence)

dithiopyr
(
Very
Early
Postemergence)

fluazifop
(
Postemergence)
atrazine
(
St.
Augustine
and
Zoysia
only)

2,4­
D,
dicamba,

MCPA,
MCPP,

propanoic
acid,
triclopyr
(
Postemergence)

1Voluntary
Purchasing
Groups,
Inc.,
Bonham,
Texas
75418
4Bayer
Advanced
LLC,
1500
Urbana
Center
Drive,
Birmingham,
AL
35242
2Value
Garden
Supply,
LLC.,
5927
Paint
Bank
Road,
New
Castle,
VA
5This
restriction
applies
to
lawn
rejuvenation
and
not
spot
treatment
or
edging.

3
The
Ortho
Group,
P.
O.
Box1749,
Columbus,
Ohio
43216
7
GOLF
COURSE
USES
The
maintenance
of
golf
courses
is
important
to
providing
a
consistent
product
for
customers.
While
golf
courses
can
be
found
throughout
the
country,
a
survey
of
golf
course
locations
found
that
the
state
of
Florida
ranks
first
in
the
number
of
courses
(
L.
Q.
Ma
et
al.,
2002).
The
majority
of
golf
courses
in
Florida
are
concentrated
in
the
central,
west
central
and
southeastern
parts
of
the
state.
Within
these
three
regions,
six
counties,
Palm
Beach,
Sarasota,
Collier,
Hillsborough,
Lee
and
Polk,
contain
73
percent
of
the
state's
total
number
of
courses
(
L.
Q.
Ma
et
al.,
2002).

In
a
survey
conducted
by
L.
Q.
Ma
et
al.
(
2002),
99
percent
of
the
155
Florida
respondents
stated
that
the
"
major
turfgrass
type"
grown
on
their
facility
was
Bermuda,
with
the
next
highest
being
Bermuda/
Perennial
Rye.
When
questioned
about
problems
on
these
golf
courses,
25
percent
of
the
respondents
stated
that
weeds
were
among
their
management
problems.
Of
the
weeds
in
Florida
golf
courses,
approximately
61
percent
of
respondents
stated
that
dallisgrass
was
considered
to
be
the
most
prevalent
species,
while
crabgrass
was
second
at
35
percent.

Control
of
grass
weed
species
in
turfgrass
can
be
difficult
under
any
circumstances.
The
primary
manner
in
which
grass
weeds
such
as
crabgrass
and
dallisgrass
can
be
effectively
controlled
is
through
the
maintenance
of
a
high
quality
turf
such
as
is
the
case
in
almost
all
golf
courses.
However,
when
chemical
control
of
grass
weeds
is
required
there
are
only
a
few
herbicides
that
can
accomplish
this
selectively.
Selective
grass
control
in
a
golf
course
turf
includes
an
organic
arsenical
herbicide,
MSMA,
as
well
as
one
of
a
few
preemergence
herbicides.
Within
a
commercial
turfgrass
maintenance
program
such
as
in
a
golf
course
business,
accurate
timing
for
preemergence
weed
control
applications
is
the
norm
rather
than
the
exception.

ALTERNATIVES
Alternatives
to
the
OA
herbicides
in
golf
course
maintenance
include
many
ai,
both
preemergence
and
postemergence.
There
is,
however,
no
direct
replacement
for
the
DSMA/
MSMA
selective
control
of
broadleaf
and
grass
weeds
in
golf
course
turf.
Table
2
includes
OA
alternatives
based
on
the
turf
species
designated
by
the
registrant
as
those
that
will
be
supported
in
re­
registration.
Table
2
lists
the
alternatives
to
control
the
weed
species
for
which
80
percent
of
the
reported
golf
course
acreage
was
treated
with
DSMA/
MSMA;
within
each
type
grass,
broadleaf
and
sedges
were
controlled
(
EPA
Proprietary
Data).

In
determining
alternatives
for
MSMA
in
a
specific
turf
species,
Table
2
lists
herbicides
that
can
be
applied
based
upon
the
two
categories
of
weeds,
broadleaf
and
grasses
and
nutsedge.
The
herbicide
combinations
listed
for
each
turfgrass
species
would
be
considered
the
best
case
scenario
(
Table
2).
The
herbicide
scenarios
listed
assume
that
all
of
the
weeds
listed
for
Table
2
would
be
present
and
would
require
some
level
of
control.
This
is
highly
unlikely
since
golf
courses
are
well
maintained
and
rely
on
preventative
measures
to
remain
so.
It
is
likely
that
MSMA
would
be
used
to
treat
only
few
species.
While
there
still
remains
questions
as
to
whether
there
is
any
herbicide
that
can
control
dallisgrass
and
bull
paspalum,
MSMA
does
seem
to
offer
some
level
of
control.
Without
MSMA,
there
would
not
be
an
herbicide
that
offers
any
level
of
control.

A
comprehensive
economic
analysis
was
not
attempted
due
to
the
lack
of
information
on
golf
course
economic
data.
Operating
costs
and
revenues
of
golf
courses
remain
confidential
business
8
information
therefore
only
a
comparison
of
the
average
chemical
costs
per
acre
are
highlighted
in
Table
3.

Table
2.
MSMA
alternative
herbicides
used
in
commercial
turfgrass
for
selective
weed
control
of
goosegrass,
crabgrass,
dallisgrass,
crowfootgrass,
bahiagrass,
annual
bluegrass,
bull
paspalum,
clover,
dandelion,
dollarweed,
and
yellow
nutsedge.

Alternatives
Turfgrass
Species1
Preemergence
Postemergence
Additional
Information
Cool
Season
Turfgrasses
Ryegrass
Kentucky
Bluegrass
Tall
Fescue
Bentgrass
Fine
Fescue
prodiamine
or
oxadiazon
2,4­
D2;
halosulfuron
Warm
Season
Turfgrasses
Bermudagrass
2,4­
D3
St.
Augustine
atrazine5
Zoysiagrass
napropamide
&
oryzalin
atrazine
 
Crowfootgrass
and
Goosegrass
are
common
names
for
Eleusine
indica6.

 
Dallisgrass
occurring
in
turfgrass
has
no
selective
controls
other
than
DSMA/
MSMA.
Nonselective
controls
such
as
diquat,
glufosinate,
glyphosate
and
are
the
only
alternative.

 
"
Dallisgrass
[
Paspalum
dilatatum
Poir.]
Field
Paspalum
[
Paspalum
laeve
Michx.]
Thin
(
or
Bull)
Paspalum
[
Paspalum
setaceum
Michx.]
This
group
of
paspalums
resemble
one
another
very
closely,
and
field
paspalum
and
thin
paspalum
are
often
mistakenly
called
dallisgrass.
All
three
are
perennials
and
management
is
the
same.
They
are
common
and
are
some
of
the
more
difficult­
tocontrol
weeds
in
turfgrasses.
The
only
proven
way
to
selectively
remove
this
group
of
paspalums
is
multiple
applications
of
arsonate
herbicides
in
the
early
spring
in
tolerant
turfgrass
species."
(
Bruneau,
A.
H)

Source:
(
Anonymous,
2006a;
Boehm
et
al.
2004;
Bruneau
ed,
2005;
Burgess;
Dernoeden,
1996,
1999,
2004;
Elmore
et
al.,
2003,
2005;
Fresen;
Landschoot,
2004,
2006;
McCarty,
1995;
McCarty
et
al.,
1999a;
McCarty
et
al.,
1999b;
Unruh
and
Brecke,
1998;
Uva
et.
al.,
1997)
1Of
the
total
golf
course
area
treated
with
MSMA
and
DSMA,
80%
were
treated
for
these
targeted
pests
within
each
type
(
Grass,
Broadleaf
and
Sedges).
2
2,4­
D
provids
fair
control
for
some
of
the
clovers;
dollarweed
control
is
rated
fair
to
excellent
(
McCarty
et
al.,
1999b)
3
Safe
to
Intermediate
for
these
species
based
on
University
of
Florida,
IFAS
Extension
guidelines
(
Unruh
and
Brecke,
1998)
5
Not
registered
in
California
for
this
use
(
Elmore
et
al.,
2003)
6
Uva,
R.
B.,
J.
C.
Neal,
and
J.
M.
DiTomaso.
1997.
Weeds
of
the
Northeast.
Cornell
University
Press.
Ithaca,
NY
14850
9
Table
3.
Average
Cost
of
Organic
Arsenicals
and
its
Alternatives
Active
Ingredient
Average
Cost
Total
Area*
($/
acre)
Change
in
Cost
($/
acre)**
(
between
MSMA
and
Alternatives)
MSMA
$
9
$
0
Organic
Arsenical
DSMA
$
11
$
2
2,4­
D
$
5
­$
4
ATRAZINE
$
5
­$
4
HALOSULFURON
$
85
$
76
ORYZALIN
$
41
$
32
OXADIAZON
$
104
$
95
Alternatives
PRODIAMINE
$
38
$
29
*
Source:
EPA
proprietary
data.
**
Assuming
a
one
to
one
substitution.

COTTON
WEED
CONTROL
Weed
control
in
cotton
grown
in
the
southern
United
States
and
California
often
includes
one
of
the
OA
herbicides.
When
used
in
cotton,
MSMA
and
DSMA
can
be
applied
as
a
burn­
down
application
prior
to
planting,
or
postemergence/
post­
directed
in
a
tank
mix
with
preemergence
herbicides.
Many
applicators,
farm
managers,
and
university
researchers
think
of
MSMA
and
DSMA
as
directly
interchangeable.
While
these
two
herbicides
are
distinctly
different
active
ingredients,
for
simplification
this
discussion
will
treat
DSMA/
MSMA
as
analogous
to
"
DSMA
and
MSMA"
or
either
of
the
two
individuals.

Currently,
there
is
not
a
single
alternative
available
to
replace
DSMA/
MSMA,
with
the
exception
of
glyphosate
applied
to
glyphosate
tolerant
cotton.
Table
4
lists
the
weed
species
for
which
80
percent
of
the
DSMA/
MSMA
treated
cotton
acreage
was
treated.
The
remaining
20
percent
of
the
weed
species
were
not
considered
to
be
a
major
focus
for
DSMA/
MSMA
weed
control.
In
addition,
this
table
also
includes
a
list
of
the
alternatives
available
to
control
these
weeds.
An
example
of
an
herbicide
treatment
to
replace
DSMA/
MSMA
for
preemergence
weed
control
in
cotton
could
include
metolachlor
and
diuron.

The
alternatives
listed
in
Table
4
have
some
limitations,
however.
As
mentioned
above,
postemergence
treatments
of
glyphosate
can
only
be
use
if
glyphosate
tolerant
cotton
is
planted.
EPTC
controls
red
root
pigweed,
sicklepod,
and
prickly
sida,
but
only
at
high
rates
under
conditions
suitable
for
germination.
Halosulfuron­
methyl
controls
broadleaf
weeds,
but
not
sicklepod,
prickly
sida,
or
bristly
starbur.
Norflurazon
provides
only
suppression
for
nutsedge,
bermudagrass,
cocklebur,
morningglory,
pigweed,
and
sicklepod.
It
does
not
provide
control
or
suppression
of
bristly
starbur.

HARVEST
AID
Cacodylic
acid
is
used
in
cotton
primarily
as
a
harvest
aid.
As
a
defoliant/
desiccant,
it
causes
rapid
drying
of
leaf
tissue
and
also
defoliation
prior
to
harvest.
In
addition
to
these
two
functions,
cacodylic
acid
offers
the
added
benefit
of
"
ripening",
or
desiccating
the
bolls
to
the
point
that
they
crack
open.
When
applied
as
a
harvest
aid,
cacodylic
acid
also
acts
as
a
contact
weed
control
for
any
weeds
remaining
in
the
field
that
may
get
caught
in
the
harvester,
thus
reducing
harvest
and
staining
the
lint.
Alternatives
chemistries
that
offer
the
same
functions
as
cacodylic
acid
are
listed
in
Table
5.
10
Data
on
cacodylic
acid
use
are
less
reliable
than
for
the
other
organic
arsenicals.
Table
6
shows
all
of
the
observations
on
cacodylic
acid
use
available
from
the
National
Agricultural
Statistics
Service
from
1999
 
2003.
Although
the
National
Agricultural
Statistics
Service
does
not
report
data
on
pesticide
use
on
cotton
every
year,
there
are
fewer
observations
of
cacodylic
acid
use
than
the
other
organic
arsenicals.
Based
on
the
data
in
Table
6,
and
earlier
data
from
the
same
source
that
is
not
shown
in
the
table,
cacodylic
acid
use
appears
to
be
concentrated
in
California.
Data
on
pesticide
use
in
California
is
also
available
from
the
California
Department
of
Pesticide
Regulation.

Table
4.
Weed
species
controlled
by
organic
arsenical
herbicides
in
agronomic
production
Alternative
Herbicides
Organic
Arsenical
Herbicide
Weed
Common
Names1
Preemergence
Postemergence
Sedges
&
Grasses
MSMA
Nutsedge
EPTC3,4
metolachlor
norflurazon6
pendimethalin
prometryn
pyrithiobac­
sodium
trifuralin
fluometuron
glyphosate2
halosulfuron­
methyl5
MSMA
Barnyardgrass
MSMA
Bermudagrass
MSMA
Crabgrass
MSMA,
DSMA
Johnsongrass
MSMA
Signalgrass,
Broadleaf
diuron
EPTC3,4
norflurazon6
pendimethalin
trifluralin
clethodim
fenoxaprop
Fluazifop
glyphosate2
halosulfuron­
methyl5
Broadleaf
Weeds
MSMA,
DSMA
Cocklebur
MSMA,
DSMA
Morningglory
MSMA,
DSMA
Pigweed,
Redroot
MSMA,
DSMA
Sicklepod
MSMA
Sida,
Prickly
MSMA
Starbur,
Bristly
diuron
EPTC3,4
norflurazon6
prometryn
fluometuron
glyphosate2
halosulfuron­
methyl5
pyrithiobac­
sodium
Source:
Bacheler
et
al.,
2005;
Culpepper
and
Brown,
2005;
Keddig
et
al.,
2005;
Keddig
et
al.,
1994;
McCarty
et
al.,
2002;
Ware,
1994
1Targeted
pests
for
80%
of
the
total
agronomic
crop
area
treated
with
MSMA
and
DSMA;
within
each
weed
type
(
Grass,
Broadleaf
and
Sedges).
2Only
for
use
with
transgenic
crops.
3Preplant
Incorporated
(
PPI).
4
Red
Root
Pigweed,
Sicklepod,
and
Prickly
Sida
only
at
high
rates
under
conditions
for
germination.
5
Cocklebur,
Morningglory,
and
Red
Root
Pigweed
only.
6
Nutsedge,
Bermudagrass,
Cocklebur,
Morningglory,
Pigweeds,
Sicklepod,
suppression
only.
Bristly
Starbur
is
not
controlled
or
suppressed.
11
Table
5.
Alternative
harvest
aids
for
cacodylic
acid
in
cotton.
(
Hutmacher,
R.
B.
et
al.
2003;
Vencill
ed,
2002;
Ware,
1994).
Alternative
Chemistries
Organic
Arsenical
Desiccant
Desiccant
Defoliant
Boll
Ripening
diquat
dimethipin
dimethipin
endothall
ethephon
ethephon
paraquat
paraquat
sodium
chlorate
thidiazuron
cacodylic
acid
sodium
chlorate
Source:
Hutmacher,
R.
B.
et
al.
2003;
Vencill
ed,
2002;
Ware,
1994.

Table
6.
Cacodylic
Acid
Use
1999
 
2003*

State/
Area
Year
Active
Ingredient
Applied
(
pounds)
Percent
Crop
Treated
Application
Rate
(
pounds
AI
per
Acre
per
Year)
All
Program
States***
1999
46,000
**
0.41
All
Program
States
2000
108,000
1
0.72
All
Program
States
2001
95,000
**
0.92
California
1999
36,000
11
0.55
California
2000
82,000
12
0.9
Source:
USDA
NASS
Database:
http://
www.
pestmanagement.
info/
nass/
*
No
data
were
reported
for
2003
for
this
chemical,
even
though
cotton
pesticide
data
was
reported.
**
Not
available
***"
All
Program
States"
are
those
states
which
USDA
NASS
survey
for
pesticide
use
on
a
given
crop.
They
try
to
survey
the
largest
states
in
order
to
cover
the
area
that
accounts
for
at
least
80%
of
the
total
production.

Table
7
shows
use
of
cacodylic
acid
on
cotton
in
California,
based
on
data
from
the
California
Department
of
Pesticide
Regulation.
The
use
of
cacodylic
acid
in
California
has
been
trending
downward
sharply,
beginning
in
the
late
1990s.
Before
the
downward
trend,
California
was
the
only
state
that
showed
significant
use
of
cacodylic
acid
on
a
regular
basis
based
on
NASS
data.
While
data
from
NASS
are
not
available
in
every
year,
the
California
Department
of
Pesticide
Regulation
reports
pesticide
use
annually
(
California
Department
of
Pesticide
Regulation).
These
data
also
show
a
downward
trend
in
use,
with
current
use
very
close
to
zero.
In
2004,
only
100
acres
of
cotton
were
treated
with
a
total
of
115
pounds
of
cacodylic
acid
in
California.
Because
of
the
very
minimal
use
data
for
cacodylic
acid
in
cotton,
we
will
not
analyze
it
further
in
this
document.

Table
7.
Pounds
of
Cacodylic
Acid
Used
in
California
1994
­
2004
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
43,685
43,275
31,417
26,060
17,379
15,930
16,093
3,983
1,795
207
115
Source:
California
Department
of
Pesticide
Regulation
12
ECONOMIC
ANALYSIS
CROP
PRODUCTION
Cotton
is
a
major
crop
in
the
United
States,
with
a
total
value
of
production
averaging
over
$
4.5
billion
(
see
Table
8).
There
are
two
categories
of
cotton
grown
in
the
U.
S.
Upland
cotton
is
grown
from
Texas
in
the
west,
throughout
the
southeast
to
the
Atlantic
Coast,
extending
as
far
north
as
Kansas
and
Missouri.
Pima
cotton
is
a
more
valuable,
longer
staple
cotton
grown
in
California,
Texas,
Arizona,
and
New
Mexico.
Table
8
shows
the
area
harvested,
production,
and
the
value
of
production
for
both
types
of
cotton,
averaged
over
the
years
2001
 
2005.

ORGANIC
ARSENICAL
USE
ON
COTTON
Use
of
the
organic
arsenicals
MSMA
and
DSMA
in
cotton
has
been
trending
downward,
particularly
since
the
late
1990s.
Data
on
the
total
pounds
of
active
ingredient
applied
to
cotton
from
USDA
NASS
(
USDA
NASS
Pest
Management
Database)
was
used
to
construct
use
indices
for
MSMA
and
DSMA
used
on
cotton.
The
indices
represent
the
use
of
each
chemical
(
measured
as
total
pounds
of
active
ingredient
applied
to
cotton),
relative
to
the
use
in
1990
(
the
first
year
for
which
data
are
available).
Figure
1
shows
the
value
over
time
of
an
index
created
for
each
organic
arsenical,
relative
to
the
total
pounds
of
active
ingredient
applied
in
1992.
There
is
a
clear
downward
trend
in
the
use
of
both
arsenicals,
beginning
in
the
late
1990s.
Because
of
the
longer
time
series
(
extending
back
to
the
1990)
the
trend
is
less
obvious
visually,
but
value
of
the
indices
are
provided
for
the
last
available
data
point
in
2003.
For
DSMA,
use
in
2003
is
just
above
2
percent
of
the
use
in
1990.
For
MSMA,
use
in
2003
is
about
43
percent
of
the
use
in
1990.

There
is
a
clear
downward
trend
in
the
use
of
both
MSMA
and
DSMA,
beginning
in
the
late
1990s.
In
cotton,
the
herbicide
that
has
replaced
the
organic
arsenicals
has
been
glyphosate.
Glyphosate
market
share
has
steadily
increased
since
the
introduction
of
glyphosate
tolerant
cotton
in
the
mid­
1990'
s.
13
Table
8.
Cotton
Area
Harvested,
Production,
and
Value:
2001
­
2005
Average
Area
Harvested
Production
Value
of
Production
1,000
Acres
1,000
Bales*
1,000
Dollars
Texas
4,810
5,955
1,221,090
Georgia
1,324
1,971
431,468
Mississippi
1,228
2,191
451,680
Arkansas
974
1,917
410,207
North
Carolina
838
1,261
267,356
California
734
2,088
677,228
Louisiana
590
961
204,751
Tennessee
567
958
201,810
Alabama
548
795
167,303
Missouri
395
744
156,329
Arizona
242
649
148,033
South
Carolina
239
338
73,504
Oklahoma
195
258
54,325
Florida
101
122
27,058
Virginia
92
152
30,906
Kansas
66
71
15,841
New
Mexico
62
114
29,828
United
States
13,003
20,547
4,568,718
Source:
United
States
Department
of
Agriculture,
National
Agricultural
Statistics
Service:
Crop
Production
2003
Summary,
Crop
Production
2005
Summary,
Crop
Values
2003
Summary,
Crop
Values
2005
Summary.
*
A
standard
bale
weighs
480
pounds.
14
Table
9
shows
average
use
of
the
organic
arsenicals
MSMA
and
DSMA
on
cotton
for
each
state
for
which
NASS
reports
data,
from
1991
 
2003.
Typically,
data
are
not
reported
for
every
state
each
year,
so
the
number
of
observations
is
also
included.
The
table
shows
that
organic
arsenical
use
in
cotton
is
concentrated
in
only
a
few
states.
DSMA
and
MSMA
are
used
in
many
cotton
growing
states,
although
use
of
these
herbicides
is
also
declining
over
time,
as
shown
in
figure
1.
MSMA
and
DSMA
use
is
concentrated
in
four
states:
Mississippi,
Georgia,
Arkansas,
and
Louisiana.
The
averages
in
the
table
are
calculated
over
a
long
period:
1991
 
2003.
Even
in
these
states
where
organic
arsenicals
are
used
heavily,
use
has
been
trending
down,
so
the
averages
in
the
table
overstate
current
use.
Figure
1:
Organic
Arsenical
Use:
Index,
1990
=
100
43.03
2.05
0
100
200
1990
1992
1994
1996
1998
2000
2002
2004
Source:
Constructed
using
data
from
the
USDA
NASS
Pest
Management
Database
Index
MSMA
DSMA
15
Table
9.
DSMA
and
MSMA
Use
on
Cotton
by
State,
1991
­
2003
Average.

Active
Ingredient
Applied
(
pounds)
Applications
per
Year
Application
Rate
(
pounds
AI
per
Acre)
Percent
Crop
Treated
Number
of
Observations*
DSMA
Mississippi
258,000
1.1
1.6
11
5
Arkansas
201,111
1.2
1.2
14
9
Louisiana
188,750
1.2
1.4
13
4
Georgia
132,000
1.0
1.2
7
2
Tennessee
128,500
1.1
1.7
14
2
Alabama
90,333
1.0
1.0
15
3
MSMA
Mississippi
880,750
1.5
0.9
54
12
Georgia
755,714
1.2
1.1
41
7
Arkansas
566,083
1.5
0.9
40
12
Louisiana
527,583
1.6
0.8
50
12
North
Carolina
322,200
1.1
1.1
33
5
Alabama
194,200
1.1
1.2
27
5
Texas
177,000
1.2
0.9
3
5
Tennessee
139,800
1.1
0.9
28
5
South
Carolina
118,000
1.3
1.0
35
2
Missouri
38,667
1.1
0.6
15
3
Arizona
18,000
1.0
0.9
6
1
Source:
Calculated
from
USDA
NASS
database,
which
can
be
queried
here:
http://
www.
pestmanagement.
info/
nass/
*
NASS
does
not
report
data
for
every
state
for
every
year.
The
number
of
observations
is
the
number
of
years
for
which
data
are
reported
for
that
state.
16
ANALYSIS
OF
ALTERNATIVES
FOR
MSMA
AND
DSMA
In
this
section,
we
provide
estimates
of
the
costs
of
alternative
chemicals
to
MSMA
in
cotton.
We
do
not
provide
any
estimates
for
cacodylic
acid,
because
it
is
rarely
used.
Estimates
for
alternatives
to
DSMA
are
also
not
provided,
since
DSMA
and
MSMA
control
many
of
the
same
weeds,
and
DSMA
use
is
much
lower
than
MSMA
use
in
cotton.
Table
10
shows
the
relative
costs
of
MSMA
and
the
alternative
chemicals
identified
in
Table
4.
In
the
table,
the
weeds
that
are
controlled
by
MSMA
are
sorted
into
three
categories:
broadleaf
weeds,
grassy
weeds,
and
nutsedge.
Within
a
category
of
weeds,
all
of
the
weeds
can
be
controlled
by
the
listed
alternatives.
The
estimated
cost
of
the
chemicals
in
the
table
are
costs
for
the
chemical
only,
and
do
not
include
any
other
costs,
such
as
application
costs.
According
to
EPA
proprietary
data2
the
cost
of
MSMA
is
about
$
3
per
acre
nationwide,
although
costs
vary
from
state
to
state.
The
alternative
chemicals
in
the
table
are
more
expensive,
with
the
exception
of
Diuron.
In
addition
to
being
more
expensive,
the
alternatives
have
a
further
disadvantage
relative
to
MSMA.
MSMA
can
control
all
of
the
weeds
listed
in
Table
4,
and
can
be
used
as
both
a
pre­
and
postemergent
herbicide,
while
almost
all
of
the
alternatives
control
2
of
the
3
weed
types
at
best,
and
none
of
them
can
be
used
both
pre­
and
post­
emergence.
To
control
the
entire
weed
spectrum
currently
controlled
by
the
organic
arsenicals,
one
treatment
of
an
alternative
will
not
be
sufficient.
The
likely
outcome
is
that
one
treatment
of
two
or
even
three
different
alternative
chemicals
will
be
used.

Glyphosate
can
be
used
against
all
three
weed
types,
but
its
use
also
requires
the
planting
of
genetically­
modified
glyphosate­
resistant
cotton.
Planting
genetically
modified
cotton
requires
the
grower
to
pay
an
additional
fee
to
the
owner
of
the
technology,
which
is
not
included
in
the
table.
Glyphosate­
resistant
cotton
is
popular
with
growers,
and
it
is
available
in
varieties
that
have
also
been
genetically
modified
to
be
resistant
to
insect
pests,
as
well.
The
availability
of
herbicide
tolerant
cotton
(
beginning
in
the
mid
to
late
1990s)
probably
accounts
for
the
downward
trend
in
organic
arsenical
herbicide
use
over
that
time.
In
2005,
about
79
percent
of
all
upland
cotton
acres
were
planted
with
genetically
modified
varieties.
About
61
percent
of
all
upland
cotton
acres
were
planted
to
varieties
that
give
resistance
to
glyphosate
(
USDA
NASS,
2005).

FARM
LEVEL
IMPACTS
OF
ORGANIC
ARSENICAL
ALTERNATIVES
Most
of
the
alternatives
(
the
exception
is
diuron)
to
MSMA
will
be
more
expensive,
even
when
not
including
extra
costs
associated
with
multiple
applications.
To
provide
an
example
of
the
impact
that
will
have
at
the
farm
level,
we
use
crop
budgets
from
Mississippi
to
evaluate
the
impact
of
replacements
for
organic
arsenicals
on
cotton.
Sample
costs
for
cotton
production,
available
from
Mississippi
State
University
(
2005)
from
the
basis
of
the
economic
analysis
in
this
section;
Mississippi
was
chosen
because
there
is
more
organic
arsenical
use
in
Mississippi
than
any
other
state;
we
assume
it
is
representative
of
other
upland
cotton
producing
states.
These
crop
budgets
are
designed
to
reflect
the
costs
and
returns
for
a
typical
grower,
but
they
are
not
based
on
statistical
sampling
methods
or
surveys.
They
specify
a
chemical
program,
which
may
not
be
the
one
used
by
every
farmer,
but
they
provide
a
baseline
for
the
analysis.
In
the
Mississippi
crop
budgets,
there
are
14
scenarios,
with
different
cotton
traits
(
conventional,
or
genetically
modified
herbicide
tolerant
and/
or
Bt
varieties),
locations,
tillage
practices,
and
equipment
used.

2
EPA
proprietary
data
are
data
on
pesticide
use
purchased
from
private
sector
firms.
17
Table
10.
Estimated
Costs
of
MSMA
Alternatives
on
Cotton
Pre­
emergence
Post­
Emergence
Weeds
Controlled
Active
Ingredient
Estimated
Cost
($/
Acre)
Active
Ingredient
Estimated
Cost
($/
Acre)

MSMA
$
3
MSMA
$
3
Nutsedge
EPTC
**
Metolachlor
10
Fluometuron
7
Norfluzaron
9
Glyphosate*
7
Pendimethalin
5
Halosulfuron­
methyl
**
Prometryn
6
Pyrithiobac­
sodium
14
Trifuralin
4
Grassy
Weeds
Diuron
2
Clethodim
12
EPTC
**
Fenoxaprop
4
Norfluzaron
9
Pendimethalin
5
Fluazifop
11
Trifluralin
4
Glyphosate*
7
Halosulfuron­
methyl
**

Broadleaf
Weeds
Diuron
2
Fluometuron
7
EPTC
**
Glyphosate*
7
Norfluzaron
9
Halosulfuron­
methyl
**
Prometryn
6
Pyrithiobac­
sodium
14
Source:
EPA
Proprietary
Data
*
The
use
of
glyphosate
for
weed
control
requires
the
planting
of
a
genetically
modified
glyphosate­
resistant
cotton,
which
would
require
an
additional
fee.
**
There
are
not
enough
observations
on
EPTC
and
halosulfuron­
methyl
use
to
estimate
costs.

This
analysis
is
based
on
sample
costs
for
production
of
8­
row
conventional
cotton,
using
conventional
tillage
in
the
Delta
area.
The
analysis
focuses
on
conventional
cotton
because
MSMA
is
not
used
heavily
in
herbicide
tolerant
cotton.
18
In
this
scenario,
MSMA
was
used
for
a
late
post­
emergence
treatment
(
as
indicated
by
the
crop
budgets),
so
in
the
table
we
assume
it
will
be
replaced
with
fluometuron
and
fenoxaprop,
which
would
give
control
over
nutsedge,
grassy
weeds,
and
broadleaf
weeds.
Depending
on
the
weed
conditions
in
a
particular
field,
a
different
combination
of
alternative
chemicals
may
be
more
appropriate.
We
assume
that
there
is
no
yield
or
quality
loss
with
the
alternative
chemicals.

The
price
and
yield
data
in
Table
11
are
five­
year
historical
average
prices
and
yields
for
Mississippi.
Also
included
in
Table
11,
but
not
the
Mississippi
crop
budgets
are
estimated
government
payments
to
cotton
growers.
To
estimate
the
government
payments,
we
use
information
available
from
the
United
States
Department
of
Agriculture
Economic
Research
Service
(
USDA
ERS).
Growers
receive
payments
based
on
historical
yields
and
acreage
grown.
The
base
yield
for
the
program
is
93.5
percent
of
the
1998
 
2001
average
yield.
We
approximate
that
by
multiplying
the
assumed
yield
in
the
table
(
870
pounds
per
acre)
by
0.935.
Growers
receive
payments
on
a
maximum
of
85
percent
of
their
base
acreage.
We
approximate
that
by
multiplying
again
by
0.85,
which
gives
us
the
pounds
of
cotton
per
acre
that
are
eligible
for
government
payments
of
0.935*
0.85*
870
=
691
pounds
per
acre.
The
target
price
for
upland
cotton
is
$
0.724
per
pound,
and
growers
also
receive
$
0.0667
per
pound
direct
payments.
To
approximate
these
payments,
we
multiply
the
cotton
eligible
for
government
payments
by
$
0.0667
(
to
represent
the
direct
payment)
plus
the
difference
between
$
0.724
and
the
average
cotton
price
of
$
0.50
(
to
represent
the
difference
between
the
target
price
and
the
market
price).
In
this
example,
the
government
payments
are
estimated
to
be
about
691*((
0.724
 
0.503)
+
0.0667)
=
$
199
per
acre3.
We
did
not
estimate
the
revenue
from
the
marketing
loan
program,
because
cotton
prices
are
close
to
the
loan
price.

Our
baseline
scenario,
where
MSMA
is
used
results
in
returns
to
the
grower
of
about
$
138
per
acre4.
Using
a
combination
of
fluometuron
and
fenoxaprop
in
place
of
MSMA
results
in
an
increase
in
herbicide
costs
of
about
$
8
per
acre,
assuming
only
one
treatment
of
each.
The
alternatives
are
over
three
times
more
expensive
than
MSMA,
and
in
the
increase
in
total
herbicide
costs
is
about
14
percent.
The
increase
in
total
operating
costs
from
the
alternatives
is
only
about
1.4
percent,
but
results
in
a
drop
in
returns
from
growing
and
selling
cotton
of
over
48
percent.
Government
payments
are
a
significant
portion
of
grower
revenues.
When
we
include
estimated
government
payments,
alternatives
to
MSMA
cause
net
cash
returns
to
the
grower
to
be
reduced
by
about
5.8
percent.

3
The
calculation
shown
is
inexact,
due
to
rounding.
4
Without
including
government
payments,
the
returns
to
the
grower
would
be
negative.
19
Table
11.
Gross
returns,
production
costs
and
net
cash
returns
for
organic
arsenical
alternatives
in
Mississippi
cotton.

Base
Scenario
Alternative
Herbicide
MSMA
Fluometuron
Fenoxaprop
Both
Cotton
Production
(
pounds/
acre)
870
870
870
870
Cotton
Price
($/
pound)
$
0.50
$
0.50
$
0.50
$
0.50
Cottonseed
Production
(
pounds/
acre)
1395
1395
1395
1395
Cottonseed
Price
($/
pound)
$
0.04
$
0.04
$
0.04
$
0.04
Gross
Returns
($/
acre)
$
498
$
498
$
498
$
498
Herbicides
MSMA
($/
acre)
$
3
Alternative
Chemical
($/
acre)
$
7
$
4
$
11
Percent
Change
133.3%
33.3%
266.7%

Other
Herbicide
Costs
($/
acre)
$
54
$
54
$
54
$
54
Other
Direct
Costs
($/
acre)
$
501
$
501
$
501
$
501
Total
Operating
Costs
($/
acre)
$
558
$
562
$
559
$
566
Estimated
Government
Payments
($/
acre)*
$
199
$
199
$
199
$
199
Net
Cash
Returns
($/
acre)
$
138
$
134
$
137
$
130
Percent
Change
­
2.9%
­
0.7%
­
5.8%
Source:
Mississippi
State
University
(
2005),
EPA
Proprietary
Data,
and
calculations
from
USDA
NASS
(
2006a,
2006b,
2004a,
and
2004b).
Totals
may
differ
from
sum
of
components
due
to
rounding.
*
The
grower
receives
payments
from
the
government,
which
we
approximate
as
(($
0.724
 
$
0.503)
+
$
0.067)
per
pound
of
cotton.
This
payment
is
received
on
79.5%
of
production,
because
growers
only
receive
payments
on
the
yield
from
85%
of
their
base
acreage,
and
program
assumes
yields
of
93.5%
of
the
base
yield.
See
the
text
for
more
explanation.
20
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LABEL
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(
INCLUDES
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