UNITED
STATES
ENVIRONMENTAL
PROTECTION
AGENCY
WASHINGTON,
D.
C.
20460
March
23,
2005
OFFICE
OF
PREVENTION,
PESTICIDES
AND
TOXIC
SUBSTANCES
Memorandum
SUBJECT:
Benefits
Assessment
for
Dicofol
on
Apricots,
Peaches,
and
Nectarines
FROM:
Don
Atwood,
Entomologist
Biological
Analysis
Branch
Stephen
Smearman,
Economist
Elisa
Rim,
Economist
Economic
Analysis
Branch
Biological
and
Economic
Analysis
Division
(
7503C)

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

Peer
Review
Panel
Date:
November
24,
2004
TO:
Mika
Hunter,
Chemical
Review
Manager
Reregistration
Branch
2
Special
Review
and
Reregistration
Division
(
7508C)

SUMMARY
BEAD
was
asked
by
SRRD
to
determine
the
biological
and
economic
impact
of
proposed
dicofol
label
changes
based
on
worker
related
issues
identified
by
HED.
BEAD
believes
that
extending
the
restricted
entry
intervals
(
REI)
for
dicofol
from
12
hours
to
33
days
on
apricots,
peaches
and
nectarines
is
not
likely
to
have
biological
or
economic
impact
on
production
of
these
crops.
While
the
extended
REI
will
impact
field
activities,
there
are
other
miticides
available
which
are
as
efficacious
and
economical
as
dicofol
for
mite
control
in
California
stone
fruits.
As
the
alternative
miticides
are
currently
used
to
treat
more
acres
annually
than
dicofol,
there
is
not
likely
to
be
either
a
biological
or
economic
impact
on
California
producers.

BACKGROUND
2
Apricot
The
apricot
(
Prunus
armeniaca
L.),
family
Rosaceae,
is
a
small
to
medium­
sized
tree
with
a
spreading,
dense
canopy,
generally
kept
under
18
feet
by
pruning.
Apricots
grow
best
on
deep,
fertile,
well­
drained
soils,
and
are
moderately
tolerant
of
high
soil
pH
and
salinity.
Apricot
culture
is
most
successful
in
mild,
Mediterranean
climates
where
risk
of
spring
frost
is
limited
and
disease
pressure
is
low.
Most
apricots
ripen
in
early
to
mid­
summer.
Apricot
cultivation
is
similar
to
peaches,
requiring
good
light
exposure
for
fruit
color
development.
Common
spacing
for
trees
is
20­
24
feet.
Most
new
growth
is
removed
each
year,
exposing
spurs
to
maximal
sunlight.
Furrow
irrigation
is
most
common.

Apricots
for
drying
are
harvested
when
fully
ripe.
Apricots
for
fresh
consumption
are
hand
harvested
when
firm.
Firmness
is
a
reliable
indicator
for
ripeness.
The
number
of
days
from
full
bloom
is
a
fairly
reliable
index
given
the
relatively
stable
growing
conditions.
However,
proper
flavor
never
develops
in
fruit
picked
prior
to
physiological
maturity.
Apricots
are
usually
harvested
2­
3
times
during
the
growing
season.
Fresh
apricots
are
shipped
in
shallow
containers
to
prevent
crushing
or
bruising.
Apricots
have
an
extremely
short
shelf­
life
(
1­
2
weeks)
at
00
C
and
90%
relative
humidity.

Peaches
and
Nectarines
Peaches
and
nectarines
(
both
Prunus
persica)
are
in
the
family
Rosaceae
and
originated
in
China.
The
only
important
difference
between
the
peach
and
the
nectarine
is
that
nectarines
have
smooth
skins
and
peaches
are
fuzzy.
They
come
from
identical
trees.
Nectarines
often
originate
from
peach
seeds,
and
peaches
may
come
from
nectarine
seeds.
Botanists
are
unsure
of
which
originated
first.
It
is
impossible
to
tell
which
seeds
from
nectarine
trees
will
produce
nectarine
bearing
trees,
so
commercial
growers
graft
nectarine
producing
branches
onto
peach
trees.
The
branches
will
continue
to
produce
nectarines.
In
appearance,
nectarine
trees
are
virtually
indistinguishable
from
peach
trees.
Tree
size
and
shape,
leaves,
and
even
buds
look
the
same.
Nectarine
fruit,
however,
is
smaller
than
the
peach
and
smooth
skinned
(
looking
more
like
plums),
a
golden
yellow
with
large
blushes
of
red.
There
are
over
100
varieties
of
nectarine,
both
freestone
and
clingstone
varieties,
the
same
as
for
peaches.
Freestone
flesh
separates
from
the
pit
easily,
while
clingstone
flesh
clings
to
the
pit.
Nectarines
are
hand
harvested,
as
the
fruit
need
more
delicate
handling
than
peaches
because
they
are
bruised
more
easily.

PRODUCTION,
USE,
AND
USAGE
DATA
Apricots
The
top
producing
states
of
apricots
in
2001
through
2003
were
California
(
94%),
Utah
(.
2%),
and
Washington
(
1.7%).
There
are
over
200
different
varieties
of
apricots
in
the
U.
S.

Over
the
past
4
years,
dicofol
has
been
used
over
a
relatively
samll
acreage
for
apricot
production
in
California.
Nationally,
the
percentage
treated
acres
with
dicofol
was
5.6%
in
2001,
3
2.9
in
2002,
and
0%
in
2003.
The
most
widely
used
insecticides
for
apricots
in
2003
were
esfenvalerate
(
67%),
petroleum
distillate
(
32%),
and
Bacillus
thuringiensis
(
4%).
Table
1
illustrates
the
dicofol
use
and
usage
for
apricots
in
California
from
1999
to
2002.

Table1:
Dicofol
Use
and
Usage
for
Apricots
in
California
State
Year
Total
Bearing
Acres
Grown
Treated
Acres
Lbs.
Of
Dicofol
Applied
%
Crop
Treated
Application
Rate
California
1999
18,871
1,518
3,451
8.0%
2.3
2000
18,681
762
1,005
4.1%
1.3
2001
17,575
998
1,207
5.7%
1.2
2002
15,725
489
789
3.1%
1.6
4
yr
average
17,713
942
1,613
5.2%
1.6
Source:
California
Department
of
Pesticide
Regulation
Pesticide
Use
Reporting
data:
1999,
2000,2001,
and
2002.

Peaches
The
top
peach
producing
states
in
2001
through
2003
were
California
(
73%),
Georgia
(
5%),
South
Carolina
(
5%),
New
Jersey
(
3%),
Pennsylvania
(
3%),
and
Washington
(
2%).
Two
types
of
peaches
have
been
produced
in
the
United
States:
clingstone
varieties
and
freestone
varieties.
There
are
over
200
different
varieties
of
peaches
in
the
U.
S.

Over
the
past
4
years,
dicofol
has
been
used
for
peach
production
in
California.
Nationally,
the
average
percentage
acres
treated
with
dicofol
from
1999
to
2002
was
5%
in
2001,
0.3%
in
2002,
and
0.4%
in
2003.
The
most
widely
used
insecticides
on
peaches
in
2003
were
petroleum
distillate
(
43%),
esfenvalerate
(
39%),
phosmet
(
37%),
imidacloprid
(
23%),
and
chlorpyrifos
(
21%).
California
accounts
for
more
than
50%
of
the
total
acres
treated
with
dicofol
in
the
United
States.
In
2003
in
California
the
top
three
insecticides
in
terms
of
percent
treated
acreage
were
petroleum
distillate
(
50%),
esfenvalerate
(
38%),
phosmet
(
18%).
Dicofol
only
accounted
for
2%
percent
treated
acres.
Table
2
illustrates
the
dicofol
use
and
usage
for
peaches
in
California
from
1999
to
2002..
4
Table
2:
Dicofol
Use
and
Usage
for
Peaches
State
Year
Total
Bearing
Acres
Grown
Treated
Acres
Lbs.
Of
Dicofol
Applied
%
Crop
Treated
Application
Rate
California
1999
74,160
3,674
5,324
5.0%
1.4
2000
71,813
3,638
5,207
5.1%
1.4
2001
70,992
5,036
7,278
7.1%
1.4
2002
70,658
2,149
2,715
3.0%
1.3
4
yr
average
71,906
3,624
5,131
5.0%
1.4
Source:
California
Department
of
Pesticide
Regulation
Pesticide
Use
Reporting
data:
1999,
2000,2001,
and
2002
Nectarines
Over
90%
of
the
nectarines
grown
in
the
United
States
are
grown
in
California.
There
are
over
175
different
varieties
of
nectarines
in
the
U.
S.

The
most
widely
used
insecticides
for
nectarines
in
2003,
in
regards
to
percent
crop
treated,
were
petroleum
distillate
(
48%),
esfenvalerate
(
41%),
phosmet
(
44%),
formetanate
hydrochloride.
(
35%),
and
chlorpyrifos
(
31%).
Table
3
illustrates
the
dicofol
use
and
usage
for
nectarines
in
California
from
1999
to
2002.

Table3:
Dicofol
Use
and
Usage
for
Nectarines
State
Year
Total
Bearing
Acres
Grown
Treated
Acres
Lbs.
Of
Dicofol
Applied
%
Crop
Treated
Application
Rate
California
1999
36,122
1,940
2,654
5.4%
1.4
2000
32,987
790
1,091
2.4%
1.4
2001
34,565
1,460
2,139
4.2%
1.5
2002
34,251
471
602
1.4%
1.3
4
yr
average
34,481
1,165
1,622
3.3%
1.4
Source:
California
Department
of
Pesticide
Regulation
Pesticide
Use
Reporting
data:
1999,
2000,2001,
and
2002
TARGET
PEST
FOR
DICOFOL
IN
APRICOTS,
PEACHES,
AND
NECTARINES
Mites
can
cause
serious
problems
in
apricots,
peaches,
and
nectarines.
The
most
important
are
the
web
spinning
mites
(
two­
spotted
mite
and
Pacific
mite).
These
pests
may
occur
anytime
during
the
year
(
winter,
spring,
and
in­
season).
Winter
and
spring
populations
should
be
5
monitored
to
prevent
buildup
of
economically
damaging
numbers
later
in
the
year.

Stone
fruits
can
tolerate
some
mite
leaf
feeding
damage,
particularly
on
water
sprouts
(
suckers
that
grow
straight
up
from
the
main
limbs)
in
the
center
of
trees.
However,
high
populations
can
result
in
leaf
drop
and
poor
fruit
sizing.
If
defoliation
happens
early
in
the
season,
fruit
fails
to
size
properly,
and
limbs
and
fruit
may
be
exposed
to
sunburn.
In
addition,
high
mite
populations
in
apricots
may
also
cause
decreased
production
in
the
year
following
and
outbreak.

Web
spinning
spider
mites
overwinter
as
adult
females
in
protected
places
on
the
tree
or
in
the
litter,
trash,
and
weeds
on
the
orchard
floor.
The
mites
become
active
in
early
spring
soon
after
trees
leaf
out
and
begin
feeding
on
weeds
or
in
the
lower
part
of
the
trees.
Both
species
are
favored
by
hot,
dry
conditions,
and
as
the
weather
becomes
warmer,
they
increase
in
numbers
and
move
up
the
center
of
the
tree
until
the
entire
tree
is
infested.
Females
can
complete
a
generation
in
as
little
as
10
days
during
the
hottest
part
of
summer.
There
may
be
from
8
to
18
generations
of
spider
mites
per
year
depending
on
temperature.

ALTERNATIVE
MITICIDES
FOR
USE
IN
APRICOTS,
PEACHES,
AND
NECTARINES
Mites
can
be
effectively
controlled
using
insecticidal
soaps
and
oils.
During
the
spring
(
dormant/
delayed
dormant),
motile
mites
may
also
be
controlled
using
dicofol
or
pyridaben.
Bifenazate,
clofentezine,
and
hexythiazox
are
effective
ovicides.
Esfenvalerate,
a
synthetic
pyrethroid,
is
also
effective
but
may
cause
mite
outbreaks
through
disruption
of
the
beneficial
insect
and
mite
population.

In
season
control
of
mite
populations
is
essential
to
manage
plant
stress
during
the
hot
summer
months.
Oil
is
an
excellent
miticide
if
applied
early.
Abamectin
and
bifenazate
are
excellent
miticides.
Hexythiazox
is
an
effective
ovicide.
Clofentezine
is
also
an
effective
ovicide
but
has
a
prohibitive
PHI.
Dicofol
and
pyridaben
are
only
considered
fair
to
good
for
in
season
mite
control.

California
recommendations
for
control
of
spider
mites
on
apricots,
peaches
and
nectarines
do
not
include
dicofol.
Narrow
range
oil
is
the
only
recommended
control
during
the
dormant
and
delayed
dormant
period.
The
miticides
recommended
for
post
bloom
control
are
narrow
range
oil,
fenbutatin
oxide,
clofentezine,
and
hexythiazox.

BIOLOGICAL
AND
CULTURAL
CONTROL
OF
SPIDER
MITES
Biological
Control
­
Several
species
play
a
large
role
in
mite
control,
including
the
western
predatory
mite
,
the
six­
spotted
thrips,
the
spider
mite
destroyer,
the
brown
lacewing,
and
the
green
lacewing.
The
western
predatory
mite
is
the
most
reliable
mite
predator.
It
is
the
same
size
as
spider
mites,
but
lacks
spots
and
ranges
in
color
from
cream
to
amber
red.
This
predator
maintains
good
control
unless
the
proportion
of
leaves
with
spider
mites
is
higher
than
the
proportion
of
leaves
with
predatory
mites.
6
Cultural
Control
­
Mite
populations
can
be
impacted
by
field
conditions.
Mite
populations
can
be
suppressed
by
oiling
or
watering
roadways
and
maintaining
a
groundcover
to
prevent
the
dry
dusty
conditions
in
which
they
thrive.
Prevention
of
water
stress
in
the
trees
can
also
reduce
mite
populations
as
this
condition
results
in
higher
mite
densities
and
intensified
damage.
Mites
may
also
be
organically
controlled
using
biological
control
and
narrow
range
oil
sprays.
Proper
pruning
and
adequate
amounts
of
fertilizer
to
maintain
tree
vigor
will
also
discourage
two­
spotted
and
Pacific
mites.

BIOLOGICAL
IMPACT
OF
INCREASED
RESTRICTED
ENTRY
INTERVALS
The
current
REI
for
dicofol
application
on
stone
fruits
in
California
is
12
hours.
New
proposed
REI's
to
mitigate
worker
exposure
are
26
days
for
low
contact
field
activities
(
thinning)
and
33
days
for
high
contact
activities
(
hand
labor,
harvest)
at
the
average
application
rate
now
being
used
in
California
(
1.5
lb
AI/
acre).
Appendix
A
provides
information
on
miticide
applications
in
nectarines
and
peaches.
In
general,
apricots
follow
the
same
schedule
and
field
practices
as
nectarines
but
with
an
earlier
harvest.
Field
activities
which
are
concurrent
with
miticide
application
are
irrigation,
summer
pruning/
leaf
thinning
and
harvest.

Extension
of
the
REI
for
dicofol
to
26
days
could
make
it
difficult
for
stone
fruit
producers
to
work
applications
into
other
field
activities,
particularly
in
relation
to
summer
pruning.
It
is
likely
that
producers
will
move
to
an
alternative
miticide
in
instances
where
the
dicofol
REI
is
restricts
other
activities.
Irrigation
is
exempt
from
the
REI
restrictions
due
to
the
lack
of
contact
with
treated
trees.
Harvest
would
be
impacted
for
all
crops.
However,
due
to
different
crop
timing
for
different
peach
production
areas
in
California,
the
impact
on
harvest
will
be
variable.
Regardless,
sufficient
efficacious
miticides
with
an
acceptable
REI
are
available
for
mite
control
immediately
prior
to
harvest.

No
biological
impact
would
be
expected
from
the
extension
of
dicofol
REI's.
There
are
sufficient
numbers
of
registered
alternative
miticides
with
acceptable
efficacy
and
less
restrictive
REI's
to
fill
any
gap
in
which
dicofol
could
not
be
applied.

ECONOMIC
IMPACT
OF
INCREASED
RESTRICTED
ENTRY
INTERVALS
A
minimal
economic
impact
would
be
expected
from
the
extension
of
REI's
for
dicofol
on
stone
fruits
in
California.
Sufficient
alternative
miticides
are
available
with
comparable
pricing
to
dicofol
and
which
currently
dominate
the
market.
Currently
dicofol
is
used
on
5%
of
the
acres.
The
Table
4
below
illustrates
a
comparison
of
the
cost
per
acre
for
alternatives
to
dicofol.
The
alternatives
listed
below
include
those
that
may
be
considered
biological
alternatives
but
did
not
have
cost
information
available
due
to
a
lack
of
reported
use.
If
the
remaining
exclusive
dicofol
use
is
converted
to
the
next
best
alternative
the
following
cost
impacts
may
be
expected.
For
apricots
peaches
and
nectarines,
the
next
best
alternative
that
is
currently
in
use
is
fenbutotin
oxide.
For
apricots,
if
the
average
acreage
using
dicofol
is
converted
to
fenbutotin
oxide
the
estimated
increase
in
cost
will
be
approximately
$
49,500.
For
peaches,
the
estimated
average
7
increase
in
cost
is
approximately
$
157,500.
For
nectarines,
the
estimated
average
increase
in
cost
is
approximately
$
49,800.
The
aggregate
average
impact
is
estimated
to
be
$
256,800
annually.

Table
4.
Dicofol
Control
Alternatives
Cost
Per
Acre
Treatment
Control
AI
Product
Name
Product
Cost
per
Pound
Cost
per
Acre
Treatment
Dicofol
Dicofol
4ec
$
31.62
$
11.45
Abamectin
Agri­
mec
N/
A
N/
A
Bifenazate
Savey
$
61.02
N/
A
Clofentezine
Apollo
N/
A
N/
A
Esfenvalerate
Asana
XL
$
94.78
$
6.30
Fenbutotin
oxide
Vendex
50
WP
$
157.89
$
42.16
Formentenate
Carzol
SP
$
29.83
$
29.83
Hexythiazox
Hexagon
N/
A
N/
A
Pyridaben
Pyramite
$
29.83
$
29.83
Oil
Oil
Damoil
$
3.40
$
10.70
Sources:
USDA
Agricultural
Statistics
2003,
EPA
proprietary
data.

CONCLUSIONS
There
will
be
no
biological
impact
from
extension
of
the
REI
for
dicofol
on
apricots,
peaches
and
nectarines.
Dicofol
can
still
be
used
but
producers
will
have
to
schedule
field
activities
around
the
extended
REI.
For
growers
still
using
dicofol
exclusively,
the
aggregate
impact
is
estimated
to
be
$
256,800
annually.
The
lack
of
support
for
dicofol
in
California
state
recommendations
and
the
low
number
of
acres
treated
annually
with
this
miticide
(
5%
or
less),
indicate
that
other
miticides
are
currently
dominating
the
market
for
these
crops.
This
also
supports
BEAD's
conclusion
that
extension
of
the
REI
will
have
no
impact
on
the
biological
or
economic
production
of
these
stone
fruits
in
California.

REFERENCES
UC
Pest
Management
Guidelines
­
Apricots.
http://
www.
ipm.
ucdavis.
edu/
PMG/
selectnewpest.
apricots.
html
8
UC
Pest
Management
Guidelines
­
Peaches
http://
www.
ipm.
ucdavis.
edu/
PMG/
selectnewpest.
peach.
html
UC
Pest
Management
Guidelines
­
Nectarines.
http://
www.
ipm.
ucdavis.
edu/
PMG/
selectnewpest.
nectarine.
html
A
Pest
Management
Strategic
Plan
for
Peach
Production
in
California.
2003.
http://
www.
ipmcenters.
org/
pmsp/
pdf/
CAPEACHPMSP.
pdf
A
Pest
Management
Strategic
Plan
for
Nectarine
Production
in
California.
2003.
http://
www.
ipmcenters.
org/
pmsp/
pdf/
CANECTARINEPMSP.
pdf
USDA
Crop
Profiles
for
Peaches
in
California.
1999.
http://
www.
ipmcenters.
org/
cropprofiles/
docs/
capeaches.
html
USDA
Crop
Profiles
for
Nectarines
in
California.
2001
http://
www.
ipmcenters.
org/
cropprofiles/
docs/
canectarines.
html
Personal
communication
with
Rick
Melnicoe.
Director,
Western
Integrated
Pest
Management
Center.
November
2004.

Personal
communication.
Gary
VanSickle
­
California
Tree
Fruit
Agreement.
November
5,
2004.
9
APPENDIX
A
Crop
Development
J
F
M
A
M
J
J
A
S
O
N
D
Dormancy
Bud
Break
Bloom
Pollination
Fruit
Development
Harvest
Post­
Harvest
Storage
Cultural
Practices
J
F
M
A
M
J
J
A
S
O
N
D
Cultivation
Irrigation
Pruning
­
Dormant
Frost
Protection
Girdling
Fertilizer
Application
Summer
Pruning
Pest
Management
Activities
J
F
M
A
M
J
J
A
S
O
N
D
Soil
Sampling
Scouting
Mitcide
Application
Dormant
Applications
Fungicide
Applications
Use
of
Pheromones
Herbicide
Applications
Nematicide
Applications
Vertebrate
Control
10
