| Herbicide |
Amount/Acre |
P.H.I.+ |
| (trade name) |
|
(days) |
|
| PREPLANT |
| A. |
METAM SODIUM*
| 50–75 gal
|
|
| |
(Vapam) |
|
|
| |
Comments: A soil fumigant. Beds must be free of
large clods and moistened by rainfall or irrigation 1 week before
application. Soil temperature should be between 59° and
90° F at the 3-inch depth. Broadcast rate is 50–75
gal/acre, but band applications may be made on the bed to lessen
the overall application rate. The label requires a 14-day preplant
interval between application and planting. Avoid moving untreated
soil into the banded area. |
| |
|
|
|
| B. |
METHYL BROMIDE/CHLOROPICRIN*
|
| |
(Terr-O-Gas, etc.) |
Label rates |
|
| |
COMMENTS: A soil fumigant. Beds must be free of
large clods and moistened by rainfall or irrigation 1 week before
application. Soil temperature should be between 59° and
90° F at the 3-inch depth. Immediately tarp the treated
area following application to seal in the fumigant. The interval
between treatment and planting will vary depending on rates
and soil temperature. |
| |
|
|
|
| STAND ESTABLISHMENT |
| A. |
GLYPHOSATE |
|
|
| |
(Roundup) |
0.25–5 lb a.i.
|
|
| |
|
0.25–5 qt
|
|
| |
...OR... |
|
|
| |
(Touchdown) |
0.375–3.75 lb a.i.
|
|
| |
|
0.5–5 qt
|
|
| |
COMMENTS: A nonselective foliar herbicide used
to control small annual weeds in finished beds before the asparagus
emerges. Asparagus emerged at the time of treatment will be
killed. |
| |
|
|
|
| B. |
PARAQUAT* |
0.65–1 lb a.i.
|
6
|
| |
(Gramoxone Max) |
1.7–2.7 pt
|
|
| |
COMMENTS: A nonselective foliar herbicide without
soil activity applied as a band or broadcast treatment before
or after planting, but before the asparagus emerges. Asparagus
that has emerged at the time of application will be killed.
Apply when weeds are succulent and less than 16 inches high;
larger weeds are less affected. Surfactant is needed. Late afternoon
applications increase activity. |
| |
|
|
|
| C. |
NONANOIC ACID
| 2.25–14 gal/broadcast acre
|
|
| |
(Scythe) |
3%–7% spray solution
|
|
| |
COMMENTS: A contact, nonselective foliar herbicide
without residual activity. The degree of control is greater
when weeds are actively growing, small, and immature; larger
weeds are less affected. Apply as a band treatment over the
crop row or as a broadcast treatment at or before planting.
Provides control of annuals and some suppression of perennials.
For best results, target weeds should be thoroughly wetted with
spray solution but not to the point of runoff. Use 75-200 gal
spray solution/broadcast acre, with higher volume used when
weed density is high. A 3-5% solution is sufficient for most
annual weeds while perennial or large annual weeds require a
7% solution. |
| |
|
|
|
| D. |
LINURON |
0.5–1 lb a.i.
|
1
|
| |
(Lorox) |
1–2 lb
|
|
| |
COMMENTS: Can be applied over the top to direct-seeded,
transplanted, or crown plantings when ferns have 6–18
inches of growth. Has excellent activity on small emerged annual
weeds. Do not apply with an adjuvant or in a fertilizer mix. |
| |
|
|
|
| E. |
SETHOXYDIM |
0.29–0.47 lb a.i.
|
|
| |
(Poast) |
1.5–2.5 pt
|
|
| |
COMMENTS: For use on direct-seeded or transplanted
plantings. Apply to actively growing grasses that are not under
moisture stress; best applied 2–4 days after a rain or
irrigation. Apply in 10–20 gal water plus an oil concentrate
at the rate of 1 qt/acre. Rates dependent on grass size and
species. Follow label instructions regarding the use of adjuvants. |
| |
|
| F. |
DIURON |
0.8–1.6 lb a.i.
|
|
| |
(Karmex, Direx) |
1–2 lb
|
|
| |
COMMENTS: For use on crown-planted plants in the
San Joaquin Delta only. Considered to be a groundwater contaminant
and requires a use permit within Groundwater Protection Areas.
Soils should have greater than 2% organic matter; crowns must
be buried at least 2 inches deep. Use lower rates on coarse-textured
soils. |
| |
|
|
|
| G. |
FLUAZIFOP-P-BUTYL |
0.19 lb a.i.
|
|
| |
(Fusilade DX) |
12 oz
|
|
| |
COMMENTS: For use on asparagus that is either
direct-seeded, transplanted, or crown planted. Apply in 20–40
gal water/acre along with a 1% crop oil concentrate. Rates depend
on grass size and species. Follow label instructions regarding
the use of adjuvants. |
| |
|
ESTABLISHED CUTTING BEDS
Preemergence (When spears are not present) |
| A. |
GLYPHOSATE |
|
|
| |
(Roundup) |
0.25–5 lb a.i.
|
|
| |
|
0.25–5 qt
|
|
| |
...OR... |
|
|
| |
(Touchdown) |
0.375–3.75 lb a.i.
|
|
| |
|
0.5–5 qt
|
|
| |
COMMENTS: A nonselective foliar herbicide used
to control small annual weeds in finished beds before spears
emerge. Asparagus spears emerged at the time of treatment will
be damaged and should be discarded. Use the higher rate to control
perennial weeds. |
| |
|
|
|
| B. |
PARAQUAT* |
0.65–1 lb a.i.
|
6
|
| |
(Gramoxone Max) |
1.7–2.7 pt
|
|
| |
COMMENTS: A nonselective foliar herbicide without
soil activity applied as a band or broadcast treatment before
spears emerge. Asparagus that has emerged at the time of application
will be damaged. Apply when weeds are succulent and 16 inches
high; larger weeds are less affected. Surfactant is needed.
Late afternoon applications increase activity. |
| |
|
|
|
| C. |
NONANOIC ACID
| 2.25–14 gal/broadcast acre
|
|
| |
(Scythe) |
3%–7% spray solution
|
|
| |
COMMENTS: A contact, nonselective foliar herbicide
without residual activity. The degree of control is greater
when weeds are actively growing, small, and immature; larger
weeds are less affected. Apply as a band treatment over the
crop row or as a broadcast treatment at or before planting.
Provides control of annuals and some suppression of perennials.
For best results, target weeds should be thoroughly wetted with
spray solution but not to the point of runoff. Use 75-200 gal
spray solution/broadcast acre, with higher volume used when
weed density is high. A 3-5% solution is sufficient for most
annual weeds while perennial or large annual weeds require a
7% solution. |
| |
|
|
|
| D. |
METRIBUZIN |
1–2 lb a.i.
|
14
|
| |
(Sencor) DF 75 |
1.33–2.66 lb
|
|
| |
COMMENTS: Apply to soil; metribuzin has both soil
and foliar activity on newly emerged annual weeds. Soil should
not be moved after application. Rainfall or irrigation necessary
for activation of this herbicide. |
| |
|
|
|
| E. |
DIURON |
0.8–3.2 lb a.i.
|
|
| |
(Karmex, Direx) |
1–4 lb
|
|
| |
COMMENTS: Apply as a band or broadcast treatment
to weedfree beds no earlier than 4 weeks before spears emerge;
a second application may be made following harvest. Incorporate
mechanically or with irrigation if rainfall does not occur.
Considered to be a groundwater contaminant and requires a use
permit within Groundwater Protection Areas. Do not use on soils
with less than 2% organic matter; use lower rates on coarse-textured
soils. |
| |
|
|
|
| F. |
NORFLURAZON* |
1.97–3.93 lb a.i.
|
14
|
| |
(Solicam) DF |
2.5–5 lb
|
|
| |
COMMENTS: Apply in a minimum of 20 gal water/acre
as a broadcast preemergent treatment. Read label regarding crop
rotation restrictions. Considered to be a groundwater contaminant
and requires a use permit within Groundwater Protection Areas. |
| |
|
|
| G. |
NAPROPAMIDE |
4 lb a.i.
|
|
| |
(Devrinol) 50 DF |
8 lb
|
|
| |
COMMENTS: Apply to weed-free soil in established
beds. Requires shallow (1–2 inch) mechanical incorporation,
and if rain fall does not occur, it must be irrigated. |
| |
|
|
| H. |
TRIFLURALIN |
0.5–2 lb a.i.
|
|
| |
(Treflan, and others) |
|
| |
COMMENTS: Apply to established asparagus after
bed preparation but before spears emerge. Trifluralin has no
postemergence activity on weeds and must be mechanically incorporated
immediately after application with disks or rolling cultivators
in two directions or with a power driven incorporator in one
direction. Higher rates necessary for the suppression of field
bindweed. |
| |
|
|
| I. |
LINURON |
0.5–1 lb a.i.
|
1
|
| |
(Lorox) |
1–2 lb
|
|
| |
COMMENTS: A soil-applied herbicide noted for its
foliar activity on small seedling, broadleaf weeds and for its
relatively short soil residual activity. Can be applied immediately
after cutting, but do not harvest within one day after application.
Do not apply more than 4 lb a.i./acre/season with a maximum
of 3 applications/ year. |
| |
|
|
| J. |
FLUAZIFOP-P-BUTYL |
0.19 lb a.i.
|
|
| |
(Fusilade) DX |
12 oz
|
1
|
| |
COMMENTS: Do not apply more than 24 fl oz/acre/season.
Do not make sequential applications at less than a 3-week interval. |
| |
|
ESTABLISHED CUTTING BEDS
Postemergence (After spears emerge) |
| A. |
DICAMBA* |
0.25–0.5 lb a.i.
|
1
|
| |
(Banvel) |
0.5–1 pt
|
|
| |
COMMENTS: Apply immediately after cutting but
at least 24 hours before the next harvest. Postharvest applications
should be done as directed sprays to avoid fern contact. Do
not use in Coachella Valley. Do not exceed 1 pt/acre/season. |
| |
|
|
| B. |
LINURON |
0.5–1 lb a.i.
|
1 |
| |
(Lorox) |
1–2 lb
|
|
| |
COMMENTS: A soil-applied herbicide noted for its
foliar activity on small seedling, broadleaf weeds and for its
relatively short soil residual activity. Can be applied immediately
after cutting, but do not harvest within one day after application.
Do not apply more than 4 lb a.i./acre/season with a maximum
of 3 applications/ year. |
| |
|
|
| C. |
HALOSULFURON |
0.024–0.047 lb a.i.
|
1
|
| |
(Sandea) |
0.5–1 lb
|
|
| |
COMMENTS: May be applied before or during harvest
season. Do not use adjuvant with any applications made before
or during harvest. Check label for regional constraints. |
| |
|
|
ESTABLISHED CUTTING BEDS
Postharvest |
| A. |
GLYPHOSATE |
|
|
| |
(Roundup) |
0.25–5 lb a.i.
|
|
| |
|
0.25–5 qt
|
|
| |
...OR... |
|
|
| |
(Touchdown) |
0.375–3.75 lb a.i.
|
|
| |
|
0.5–5 qt
|
|
| |
COMMENTS: A nonselective foliar herbicide used
to control both annual and perennial weeds. Use on clean cut
beds after all remaining spears have been removed. Higher rates
of application are necessary for the control of perennial weeds.
Direct contact of the spray to asparagus can cause serious injury.
Useful as a spot treatment for the control of perennial weeds
at field edges. Do not apply within a week before the first
asparagus spears emerge. |
| |
|
|
| B. |
HALOSULFURON |
0.024–0.047 lb a.i.
|
1
|
| |
(Sandea) |
0.5–1 lb
|
|
| |
COMMENTS: May be applied at end of harvest season.
Under heavy nutsedge pressure split applications are recommended.
Use drop nozzles to improve coverage on weeds and reduce contact
with fern. |
| |
|
|
|
|
|
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