UC IPM: Information about Herbicides in Strawberry

UC Pest Management Guidelines

Common name

Amount/Acre**

R.E.I.+

P.H.I.+

(trade name)

(hours)

(days)

When choosing a pesticide, consider information relating to environmental impact.

PREPLANT

METHYL BROMIDE*/CHLOROPICRIN*

300–400 lb

COMMENTS: The current Critical Use List only allows use where 1,3-dichloropropene can't be used because of local township limits. Fumigants such as methyl bromide are a source of volatile organic compounds (VOCs) but are not reactive with other air contaminants that form ozone: methyl bromide depletes ozone. Fumigate only as a last resort when other management strategies have not been successful or are not available.

OXYFLUORFEN

0.5 lb a.i.

(Goal) 2XL

1–2 pt

(GoalTender) 4F

0.5–1 pt

WSSA MODE OF ACTION GROUP NUMBER¹: 14

Comments: Use allowed under a special 2(ee) recommendation. If applied in fields where drip fumigation will be done, apply after beds are formed but before tarps are installed. Apply at least 30 days before transplanting for effective control of little mallow (cheeseweed) and filaree, which are not controlled well by the fumigants. To prevent injury to strawberry plants, do not use unless a plastic mulch will be installed at the time of strawberry transplanting. Water the treated soil with a light sprinkler irrigation before mulch installation to activate the herbicide (see 2(ee) label for other options).

FLUMIOXAZIN

(Chateau) WDG

3 oz

WSSA MODE OF ACTION GROUP NUMBER¹: 14

COMMENTS: Apply a minimum of 30 days before transplanting and before the plastic mulch is laid; plant strawberries through the plastic mulch. Use allowed under a Supplemental Label.

Sequential application of:

(Note: Fumigants such as 1,3-dichloropropene and metam products are a source of volatile organic compounds (VOCs) but minimally reactive with other air contaminants that form ozone. Fumigate only as a last resort when other management strategies have not been successful or are not available.)

1,3-DICHLOROPROPENE*/CHLOROPICRIN*

(Telone C35)

9–12 gal (shank)

5 days

COMMENTS: Effective for control of nematodes, soilborne fungal pathogens, and insects. One gallon of product weighs 11.1 lb.

. . . or . . .

1,3-DICHLOROPROPENE*/CHLOROPICRIN*

(InLine)

28–33 gal (drip)

5 days

COMMENTS: Effective for control of nematodes, soilborne fungal pathogens, and insects. Requires plastic mulch. Using higher rates or plastic mulch, especially virtually impermeable film (VIF), improves weed and nematode control. One gallon of product weighs 11.2 lb.

. . . or . . .

CHLOROPICRIN*

(MetaPicrin)

15–30 gal (shank)

(Tri-Clor)

15–21.85 gal (drip)

COMMENTS: A liquid that diffuses as a gas through soil. Very effective for control of soilborne fungal pathogens and insects. Drip irrigation requires an emulsifier. For shank fumigation, using higher rates or plastic mulch, especially virtually impermeable film (VIF), improves weed control. For drip fumigation the use of VIF will improve both nematode and weed control. One gallon of Tri-Clor weighs 13.7 lb; one gallon of MetaPicrin weighs 13.8 lb.

Followed 5-7 days later by:

METAM SODIUM*

(Vapam HL, Sectagon 42)

37.5–75 gal

COMMENTS: Water-soluble liquid that decomposes to a gaseous fumigant (methyl isothiocyanate). Efficacy affected by soil texture, moisture, temperature, and percent organic matter. One gallon of product contains 4.26 lb of metam sodium.

. . . or . . .

METAM POTASSIUM*

(K-Pam HL)

30–60 gal

PELARGONIC ACID

(Scythe)

3–5% volume/volume

WSSA MODE OF ACTION GROUP NUMBER¹: 27

COMMENTS: Good for controlling weeds in furrows when fumigation is planned.

Established weeds

PARAQUAT*

0.47 lb a.i.

(Gramoxone Inteon)

WSSA MODE OF ACTION GROUP NUMBER¹: 22

COMMENTS: Apply as a directed spray to the furrow bottoms using shields to prevent contact with crop plants. Avoid windy conditions. Use of a nonionic surfactant or crop oil is recommended. Do not allow contact with strawberry plants as injury or excessive residues may result. Ground application 20 gal water/acre. Do not apply more than 3 times/season.

POSTPLANT

Before weeds emerge

NAPROPAMIDE

(Devrinol)

2–4 lb a.i.

WSSA MODE OF ACTION GROUP NUMBER¹: 15

COMMENTS: May be applied to newly transplanted and established crop. Do not apply after 1st bloom. May inhibit runners. Good for controlling weeds in the row middles following drip fumigation.

FLUMIOXAZIN

(Chateau) WDG

3 oz

see comments

WSSA MODE OF ACTION GROUP NUMBER¹: 14

COMMENTS: Use allowed under a Supplemental Label. Apply with shielded or hooded sprayer to row middles only; do not apply over strawberry plants. Do not apply after fruit set.

DCPA

6–9 lb a.i.

(Dacthal) W-75

8–12 lb

WSSA MODE OF ACTION GROUP NUMBER¹: 3

COMMENTS: For new plantings apply 12 lb product/acre; for established plantings apply 8-12 lb product/acre in late summer or early fall. Do not apply from first bloom through harvest. Must be applied as banded applications over the rows. Applications can be made over strawberry plants without injury. Does not control emerged weeds.

After weeds emerge

SETHOXYDIM

(Poast)

0.28–0.47 lb a.i.

WSSA MODE OF ACTION GROUP NUMBER¹: 1

COMMENTS: Grass weed size is critical for control, but varies with species; see label. Only 1 application allowed/season. Not for aircraft application.

CLETHODIM

0.095–0.12 lb a.i.

(Prism)

13–17 fl oz

WSSA MODE OF ACTION GROUP NUMBER¹: 1

COMMENTS: Apply for control of annual grasses including annual bluegrass. For repeat applications, the minimum interval between applications is 14 days. Use 1% volume by volume crop oil concentrate in the finished spray mix.

PELARGONIC ACID

(Scythe)

3–5% volume/volume

WSSA MODE OF ACTION GROUP NUMBER¹: 27

COMMENTS: Good for controlling weeds in furrows following fumigation.

PARAQUAT*

(Gramoxone Inteon)

0.47 lb a.i.

WSSA MODE OF ACTION GROUP NUMBER¹: 22

COMMENTS: Apply as a directed spray to the furrow bottoms using shields to prevent contact with crop plants. Avoid windy conditions. Use of a non-ionic surfactant or crop oil is recommended. Do not allow contact with strawberry plants as injury or excessive residues may result. Ground application 20 gal water/acre. Do not apply more than 3 times/season.

Restricted entry interval (R.E.I.) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (P.H.I.) is the number of days from treatment to harvest. In some cases the REI exceeds the PHI. The longer of two intervals is the minimum time that must elapse before harvest.

Permit required from county agricultural commissioner for purchase or use.

Group numbers are assigned by the Weed Science Society of America (WSSA) according to different modes of action. Although weeds may exhibit multiple resistance across many groups, mode of action numbers are useful in planning mixtures or rotations of herbicides with different modes of action. For more information, see http://www.plantprotection.org/HRAC/.

UC IPM Pest Management Guidelines: Strawberry
UC ANR Publication 3468
Weeds
S. A. Fennimore, Weed Science/Plant Sciences, UC Davis/Salinas
O. Daugovish, UC Cooperative Extension, Ventura Co.
R. F. Smith, UC Cooperative Extension, Monterey Co.
Acknowledgment for contributions to the weeds section:
W. E. Bendixen, UC Cooperative Extension, Santa Barbara Co.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See How to manage pests, or in the U.S., contact your local Cooperative Extension office for assistance. /PMG/r734700411.html revised: June 9, 2008. Contact webmaster.

How to Manage Pests

UC Pest Management Guidelines

Strawberry

Herbicide Treatment Table

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