Document ID: EPA-HQ-OPP-2002-0009-0005
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2005-12-28T05:00Z

­
1­
Propargite
12/
06/
05
Response
to
Public
Comments
on
the
Reregistration
Eligibility
Decision
Comments
regarding
requests
for
exemptions
from
the
proposed
restricted­
entry
intervals
(
REIs)

Comment
#
1:
The
registrant
requested
a
1­
day
REI
exemption
for
handweeding
of
almonds.

Response:
No
crop­
specific
documentation
was
submitted
in
support
of
this
request.
According
to
the
Agency's
research,
weed
control
in
almond
orchards
is
accomplished
entirely
through
preand
post­
emergence
herbicide
applications
and
mechanical
mowing.
There
is
no
mention
of
handweeding
in
any
of
the
sources
consulted.
However,
in
the
unlikely
event
that
handweeding
is
planned
for
a
small
orchard,
the
Agency
believes
that
this
activity
could
be
readily
planned
around
a
scheduled
propargite
application.
Therefore,
the
Agency
is
not
approving
the
requested
REI
exemption
for
handweeding
of
almonds.

Comment
#
2:
The
registrant
requested
a
1­
day
REI
exemption
for
handweeding
and
thinning
of
dry
beans.

Response:
No
crop­
specific
documentation
was
submitted
in
support
of
this
request.
In
general,
weed
control
in
beans
begins
with
a
pre­
plant
tillage
operation,
followed
by
a
pre­
plant
incorporated
or
preemergence
herbicide
application.
The
herbicides
provide
4
to
6
weeks
of
residual
activity.
Weeds
emerging
after
that
time
are
controlled
by
cultivation
and/
or
herbicide
applications
between
rows.
According
to
the
Agency's
research,
handweeding
does
not
appear
to
be
a
common
practice
in
commercial
bean
production.
However,
to
the
extent
that
hand
weeding
may
be
required
in
isolated
instances,
the
Agency
does
not
believe
that
a
9­
day
REI
(
a
2­
day
increase
over
the
current
REI)
will
be
a
significant
impediment
to
bean
production.

Beans
are
generally
precision
seeded
with
specialized
planters
to
obtain
the
desired
uniform
plant
spacing
and
prevent
the
need
for
subsequent
thinning.
As
for
hand
weeding,
hand
thinning
does
not
appear
to
be
a
common
practice
in
commercial
bean
production
either.
It
is
unlikely
that
a
two
day
increase
in
the
current
propargite
REI
would
affect
the
timing
of
any
existing
hand
thinning
operation
to
the
extent
that
bean
production
is
affected.
Therefore,
the
Agency
is
not
approving
these
requested
REI
exemptions.

Comment
#
3:
The
registrant
requested
1­
day
REI
exemptions
for
handweeding
and
thinning
of
carrots
grown
for
seed.
­
2­
Response:
No
crop­
specific
documentation
was
submitted
in
support
of
this
request.
Unlike
carrots
grown
for
the
fresh
market,
which
fully
rely
on
herbicides
for
weed
control
and
may
often
depend
on
precision
seeding
to
reduce
the
need
for
labor­
intensive
thinning,
carrots
grown
for
seed
often
require
hand
weeding
and
hand
thinning.
However,
it
is
highly
unlikely
that
the
2
day
REI
proposed
in
the
RED
would
interfere
with
any
required
hand
weeding
or
hand
thinning
practice
in
carrots
grown
for
seed,
especially
since
this
represents
a
reduction
from
the
current
7
day
REI.
Therefore,
the
Agency
is
not
approving
these
requested
REI
exemptions.

Comment
#
4:
The
California
Grape
and
Tree
Fruit
League
requested
1­
day
REI
exemptions
for
irrigation,
scouting,
and
handweeding
of
cherries
(
foliar
application
after
harvest).

Response:
Requirements
regarding
early
entry
for
conducting
irrigation
activities
are
addressed
in
the
Worker
Protection
Standard
(
WPS),
and
scouting
activities
conducted
by
certified
crop
advisors
or
persons
under
their
direct
supervision
are
exempted
from
the
WPS
altogether;
therefore,
the
Agency
is
not
issuing
separate
REI
exemptions
for
those
activities.

According
to
the
Agency's
research,
post
harvest
cultural
activities
for
cherries,
other
than
scouting
and
irrigation,
include:
mowing/
disking,
pruning/
topping,
pesticide
applications,
fertilizing,
vertebrate
control,
and
tree
removal.
Hand­
weeding
is
not
listed
as
a
post­
harvest
activity
in
any
of
the
sources
found
by
the
Agency.
To
the
extent
that
handweeding
may
in
fact
be
necessary
in
isolated
instances,
the
Agency
believes
that
the
2­
day
REI
proposed
in
the
RED
will
not
be
a
significant
impediment
to
cherry
production.
Therefore,
the
Agency
is
not
approving
these
requested
REI
exemptions.

Comment
#
5:
The
registrant
requested
1­
day
REI
exemptions
for
handweeding
and
thinning
of
clover
grown
for
seed.

Response:
No
crop­
specific
documentation
was
submitted
in
support
of
this
request.
Thinning
is
not
mentioned
as
a
practice
in
the
literature
EPA
has
been
able
to
locate
on
this
crop.
Weeds
are
a
potentially
devastating
type
of
pest,
since
even
low
levels
of
seed
contamination
can
render
the
harvest
unmarketable.
However,
as
with
the
other
crops,
weed
control
appears
to
be
typically
done
with
herbicides,
of
which
a
variety
are
registered.
While
handweeding
is
listed
as
an
option
for
weed
control
in
some
production
guides,
it
is
presented
as
one
of
several
"
mechanical
cultivation"
strategies.
At
least
one
such
guide
states
that
weeds
can
be
managed
with
mechanical
cultivation
performed
every
10
to
14
days.
This
suggests
that
virtually
all
growers
can
continue
to
use
handweeding
in
those
(
probably
rare)
instances
where
they
prefer
it
over
the
less
labor
intensive
practices
of
mechanical
disking
or
herbicide
application
­
even
after
propargite
application.
Furthermore,
growers
have
the
option
of
using
bifenthrin
or
hexythiazox
instead
of
propargite
if
they
know
they
need
to
have
a
short
REI
to
control
weeds
concomitantly.
In
light
of
these
management
options,
the
Agency
believes
that
while
hand
weeding
does
occur
(
to
an
unknown
extent)
in
clover
seed
production,
an
exception
to
the
proposed
9­
day
REI
for
this
­
3­
activity
is
not
necessary.

Comment
#
6:
The
registrant
requested
a
1­
day
REI
exemption
for
scouting,
handweeding,
thinning,
and
irrigation
of
corn
(
field,
pop,
and
sweet).

Response:
As
stated
above,
requirements
regarding
early
entry
for
conducting
irrigation
activities
are
addressed
in
the
WPS,
and
scouting
activities
conducted
by
certified
crop
advisors
or
persons
under
their
direct
supervision
are
exempted
from
the
WPS
altogether;
therefore,
the
Agency
is
not
issuing
separate
REI
exemptions
for
those
activities.

No
crop­
specific
documentation
was
submitted
in
support
of
this
request.
According
to
the
Agency's
research,
handweeding
and
thinning
are
impractical
in
the
large
commercial
fields
that
produce
most
of
the
corn
in
the
USA,
and
thus
virtually
never
occurs.
Weeds
are
managed
with
herbicides,
of
which
a
variety
are
registered
for
use
in
all
corn
types,
or
disking
and
mowing
at
appropriate
times
in
the
year.
Therefore,
the
Agency
is
not
approving
these
requested
REI
exemptions.

Comment
#
7:
The
registrant
requested
1­
day
REI
exemptions
for
scouting,
handweeding,
thinning,
and
irrigation
of
cotton.

Response:
As
stated
above,
requirements
regarding
early
entry
for
conducting
irrigation
activities
are
addressed
in
the
WPS,
and
scouting
activities
conducted
by
certified
crop
advisors
or
persons
under
their
direct
supervision
are
exempted
from
the
WPS
altogether;
therefore,
the
Agency
is
not
issuing
separate
REI
exemptions
for
those
activities.

No
crop­
specific
documentation
was
submitted
in
support
of
this
request.
Given
that
the
Agency
has
proposed
to
lower
the
current
7­
day
REI
for
cotton
to
6
days
in
the
RED,
the
need
for
a
1­
day
exemption
for
handweeding
and
thinning
has
not
been
established.
Therefore,
the
Agency
is
not
approving
these
requested
REI
exemptions.

Comment
#
8:
The
registrant
requested
a
1­
day
REI
exemption
for
handweeding
and
irrigation
of
citrus
crops.
Florida
Citrus
Mutual
requested
2­
day
citrus
REI
exemptions
for
scouting
and
activities
carried
out
with
tractor
drawn
equipment.

Response:
As
stated
above,
requirements
regarding
early
entry
for
conducting
irrigation
activities
are
addressed
in
the
WPS,
and
scouting
activities
conducted
by
certified
crop
advisors
or
persons
under
their
direct
supervision
are
exempted
from
the
WPS
altogether
;
therefore,
the
Agency
is
not
issuing
separate
REI
exemptions
relating
to
those
activities.
Similarly,
the
Agency
believes
­
4­
that
under
many
circumstances
the
WPS
"
no
contact"
exemption
will
apply
to
tractor
drawn
agricultural
activities.
No
crop­
specific
documentation
was
submitted
in
support
of
the
request
for
an
REI
exemption
for
handweeding.
Agency
research
indicated
that
handweeding
appears
to
be
virtually
nonexistent
in
conventional
commercial
U.
S.
citrus
production
systems.
Weeding
is
typically
carried
out
using
pre­
emergent
herbicides,
disking,
and
mowing
row
middles,
and
growing
leguminous
cover
crops,
depending
largely
on
the
growing
region.
The
Agency,
therefore,
does
not
believe
an
exemption
for
hand
weeding
is
necessary.

Since
completion
of
the
RED,
new
worker
exposure
data
for
citrus
has
become
available.
This
data
has
been
reviewed
and
accepted
by
the
Agency.
As
a
result,
estimated
worker
risks
are
significantly
lower,
and
the
Agency
is
able
to
reduce
the
REIs
for
all
citrus
activities
from
the
proposed
36
days
to
20
days.
Given
that
this
is
an
8­
day
reduction
from
the
present
28
day
citrus
REI,
the
Agency
believes
that
this
new
REI
will
provide
growers
with
sufficient
flexibility
to
conduct
critical
field
activities
for
citrus.

Comment
#
9:
The
California
Grape
and
Tree
Fruit
League
and
the
registrant
requested
a
1­
day
REI
exemption
for
handweeding,
pruning,
scouting,
and
irrigation
of
grapes.

Response:
As
stated
above,
requirements
regarding
early
entry
for
conducting
irrigation
activities
are
addressed
in
the
WPS,
and
scouting
activities
conducted
by
certified
crop
advisors
or
persons
under
their
direct
supervision
are
exempted
from
the
WPS
altogether;
therefore,
the
Agency
is
not
issuing
separate
REI
exemptions
relating
to
those
activities.

No
crop­
specific
documentation
was
submitted
in
support
of
the
requested
exemptions
for
handweeding
and
pruning.
Agency
research
does
not
indicate
a
critical
need
for
these
activities
given
that
the
REIs
proposed
in
the
RED
are
already
12
days
shorter
than
the
current
REI
for
table
grapes
and
5
days
shorter
than
the
current
REI
for
all
other
grapes.
Moreover,
with
a
1
day
REI
exemption,
the
Agency
would
have
concerns
for
worker
risks
for
these
high
contact
activities.
Therefore,
the
Agency
is
not
approving
these
requested
REI
exemptions.

Comment
#
10:
The
registrant
requested
a
1­
day
REI
for
scouting,
irrigation,
and
handweeding
of
hops.

Response:
As
stated
above,
requirements
regarding
early
entry
for
conducting
irrigation
activities
are
addressed
in
the
WPS,
and
scouting
activities
conducted
by
certified
crop
advisors
or
persons
under
their
direct
supervision
are
exempted
from
the
WPS
altogether;
therefore,
the
Agency
is
not
issuing
separate
REI
exemptions
relating
to
those
activities.

No
crop­
specific
documentation
was
submitted
in
support
of
the
REI
exemption
request
for
­
5­
handweeding.
Agency
research
indicates
that
handweeding
is
rarely,
if
ever,
practiced
in
commercial
hops
production.
While
weeds
can
be
a
significant
pest
problem,
mechanical
cultivation
of
row
middles
is
the
typical
control
strategy.
Mulch
is
also
applied
to
suppress
weed
germination.
Various
herbicides
are
also
available
for
efficacious
chemical
control
of
weeds.
Therefore,
EPA
believes
that
an
exemption
for
hand
weeding
is
unnecessary
for
this
crop.

Comment
#
11:
The
mint
growers
association
requested
a
7­
day
REI
for
irrigation.

Response:
Based
on
a
reduction
in
maximum
labeled
application
rate
offered
by
the
registrant,
the
estimated
worker
risk
estimates
for
all
mint
activities
have
been
reduced.
As
a
result,
the
Agency
is
reducing
the
mint
REI
applicable
to
all
activities
from
the
proposed
9
days
to
7
days.

Comment
#
12:
The
registrant
requested
a
1­
day
REI
for
shaking,
irrigation,
and
handweeding
of
walnuts.

Response:
As
described
above,
provisions
of
the
WPS
address
the
needs
for
early
entry
for
irrigation
activities,
therefore
a
separate
REI
exemption
for
this
activity
is
not
being
approved.
No
crop­
specific
documentation
was
submitted
in
support
of
the
request
for
an
REI
exemption
for
handweeding.
The
Agency's
own
research
on
this
indicates
that
weeding
is
typically
handled
with
herbicides,
therefore
there
does
not
appear
to
be
a
critical
need
for
a
handweeding
exemption.
Agency
research
did
indicate,
however,
that
the
proposed
30­
day
REI
could
significantly
interfere
with
walnut
harvesting.
Since
tree
shaking
is
a
relatively
low
contact
activity,
worker
risks
would
all
remain
withing
acceptable
levels
with
an
REI
of
21
days
to
match
the
current
pre­
harvest
interval.
Therefore,
the
Agency
is
granting
a
21­
day
REI
exemption
for
tree
shaking.

Comments
on
Other
Issues
in
the
Proposed
Propargite
RED
Comment
#
13:
The
National
Potato
Council
requested
a
reinstatement
of
the
14
day
preharvest
interval.

Response:
The
proposed
reregistration
eligibility
document
did
not
change
the
existing
preharvest
interval;
it
will
remain
at
14
days
.

Comment
#
14:
The
National
Potato
Council,
citing
concerns
of
pacific
northwest
growers,
requested
removal
of
language
requiring
a
water
body
spray
buffer
zone
or,
if
a
spray
buffer
is
to
be
required,
that
irrigation
canals,
ditches,
and
furrows
be
excluded
from
such
requirement.

Response:
The
spray
buffer
label
language
is
as
follows:
­
6­
"
Do
not
apply
by
ground
within
50
ft.
or
by
air
within
75
ft.
of
lakes,
reservoirs,
rivers,
permanent
streams,
marshes,
or
natural
ponds;
estuaries
and
commercial
fish
farm
ponds."

The
Agency
believes
that
a
blanket
exclusion
from
the
spray
buffer
requirement
for
potato
fields
is
not
warranted;
however,
EPA
does
not
believe
that
spray
buffers
around
irrigation
systems
are
necessary
to
prevent
significant
exposures
to
aquatic
life
in
waters
adjacent
to
those
fields
because,
due
to
the
high
cost
of
supplying
irrigation
water
in
areas
where
propargite
is
used,
growers
generally
employ
extensive
methods
to
prevent
irrigation
water
from
leaving
their
fields.
Therefore,
the
Agency
is
not
requiring
spray
buffers
around
irrigation
canals,
irrigation
ditches,
or
irrigation
furrows.

Comment
#
15:
The
National
Potato
Council
requested
clarification
of
the
label
language
regarding
where
measurements
of
wind
speed
needed
to
be
made
prior
to
aerial
applications,
and
regarding
the
prohibition
of
pesticide
applications
when
heavy
or
sustained
rainfall
is
forecasted.

Response:
The
Agency
has
amended
the
label
language
to
state
that
measurements
may
be
made
adjacent
to
the
spray
area.
Regarding
the
application
restriction
when
rainfall
is
forecasted,
the
National
Potato
Council
was
concerned
about
potential
liability
to
growers
resulting
from
unanticipated
rainfalls.
The
Agency
believes
that
the
existing
wording
clearly
establishes
that
the
prohibition
is
tied
to
the
rain
forecast
rather
than
the
rain
itself;
thus,
no
liability
would
accrue
from
an
intense
or
sustained
rainfall
that
was
not
forecast.

Comment
#
16:
The
National
Potato
Council
requested
that
the
proposed
seasonal
limit
of
3.7
lbs.
of
active
ingredient
per
acre
("
ai/
A")
be
restored
to
4.1
lbs
ai/
A
(
2
applications
of
2.05
lbs
ai/
A).

Response:
Agency
data
from
over
a
10­
year
period
indicate
that
the
average
usage
for
propargite
on
potatoes
is
1.5
lbs
ai/
A
applied
once
per
season.
The
Agency
has
reviewed
this
request
to
restore
the
application
rate
to
2
applications
of
2.05
lbs
ai/
A
and
agrees
that,
although
rarely
needed,
a
second
application
at
maximum
labeled
rate
is
required
on
occasion
to
control
major
mite
infestations.
Based
on
the
exposure
modeling
described
in
the
environmental
risk
assessment,
the
Agency
believes
that
an
occasional
application
of
an
additional
.4
lbs
ai/
acre
on
an
annual
basis
is
unlikely
to
appreciably
increase
environmental
risk.
Moreover,
given
that
propargite
exhibits
low
toxicity
to
predator
mites
and
other
beneficial
insects,
the
Agency
believes
that
providing
growers
with
the
ability
to
apply
it
a
second
time
at
maximum
rate
is
an
important
component
of
an
integrated
pest
management
program.
Therefore,
the
Agency
is
granting
this
request
to
permit
2
applications
to
potatoes
at
a
rate
of
2.05
lbs
ai/
A.

Comment
#
17:
The
Washington
State
Potato
Commission
and
the
Mint
Industry
Research
Council
requested
that
the
proposed
21­
day
spray
intervals
be
reduced
to
14
days.
­
7­
Response:
During
development
of
the
RED,
the
registrant
agreed
to
institute
spray
intervals
of
21
days
for
several
crops
to
help
reduce
the
environmental
loading
of
propargite.
Potatoes
and
mint
were
among
the
crops
slated
for
a
21­
day
spray
interval
under
the
proposed
RED.
Recent
reports
from
potato
growers
in
Washington
State,
however,
have
indicated
that
although
1
application
of
propargite
is
typically
sufficient
to
control
spider
mites,
some
infestations
during
the
hot
and
dry
summer
months
have
required
a
second
application,
and
that
waiting
21
days
between
applications
has
resulted
in
significant
crop
losses.
Mint
growers
in
the
Pacific
Northwest
have
reported
similar
experiences
with
spider
mites.
These
mites
produce
especially
high
numbers
of
female
offspring
during
hot
and
dry
periods,
resulting
in
very
rapid
replenishment
of
mite
populations.
Mites
also
frequently
migrate
to
mint
fields
from
adjacent
potato
and
corn
fields
during
dry
summers.
These
factors,
combined
with
mint's
greater
susceptibility
to
mite
damage
during
drought
conditions,
underscore
the
importance
of
providing
growers
with
maximum
flexibility
in
treating
severe
mite
infestations
during
summer
months.
Although
the
Agency's
screening­
level
risk
model
indicates
a
reproductive
concern
for
some
bird
species
on
occasions
when
multiple
propargite
applications
are
needed,
instituting
a
14­
day
spray
interval
will
decrease
the
overall
risk
because
currently
no
spray
intervals
are
listed
on
propargite
labels.
Moreover,
the
coordinator
of
the
Washington
State
IPM
program
confirmed
the
importance
of
propargite
in
general
as
a
critical
IPM
tool
due
to
its
low
toxicity
to
predatory
mites
and
other
beneficial
arthropods.
For
these
reasons,
the
Agency
approves
the
requests
to
reduce
the
proposed
spray
intervals
for
potatoes
in
Washington
state
and
mint
from
21
days
to
14
days.