Not all registered pesticides are listed. The following are listed alphabetically. When choosing a pesticide, consider information relating to environmental impact, resistance management, the pesticide's properties, and application timing. Tank mixes may be necessary to achieve desired control; see Susceptibility of Weeds to Herbicide Control for more information on specific weed control. Always read the label of the product being used.
BEFORE STAND ESTABLISHMENT
A.
FLUMIOXAZIN
2.04 oz a.i.
(Chateau SW)
4 oz
12
NA
WSSA MODE-OF-ACTION GROUP NUMBER1: 14
COMMENTS: For annual artichokes, flumioxazin may be applied no less than 2 days prior to transplanting. For perennial artichokes, flumioxazin may be applied after planting crown pieces or "cut back" of mature plants.
B.
GLYPHOSATE
(Roundup PowerMax)
Label rates
4
NA
WSSA MODE-OF-ACTION GROUP NUMBER1: 9
COMMENTS: A nonselective foliar herbicide used immediately before transplanting or crop emergence. Rate depends on weed species and weed size. Annual weeds are best controlled when small; control is poor when weeds exceed the maximum size. Gives good annual weed control and some suppression of perennial weeds. Higher application rates are needed for perennial control. Note that the preharvest interval does not apply for preplant applications; however, for in-season wiper or hooded sprayer applications, the PHI is 14 days.
C.
PELARGONIC ACID
(Scythe)
3%–10% (volume/volume) spray solution
12
NA
WSSA MODE-OF-ACTION GROUP NUMBER1: 27
COMMENTS: A contact, nonselective foliar herbicide without residual activity for use immediately before transplanting. The degree of control is greater when weeds are actively growing, small, and immature; larger weeds are less affected. 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 per 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.
PENDIMETHALIN
(Prowl H2O, Satellite HydroCap)
Label rates
24
See comments
WSSA MODE-OF-ACTION GROUP NUMBER1: 3
COMMENTS: For annual artichokes, the application must be no less than 1 to 2 days prior to transplanting. For rates up to 3 pints, PHI is 60 days; between 3.1–8.2 pints, the PHI is 200 days. Do not feed forage or graze livestock in treated fields.
STAND ESTABLISHMENT
A.
FLUMIOXAZIN
3.06 oz a.i.
(Chateau SW)
6 oz
12
NA
WSSA MODE-OF-ACTION GROUP NUMBER1: 14
COMMENTS: Apply to annual artichokes prior to transplanting and to perennial artichokes prior to cracking for preemergence weed control.
B.
PRONAMIDE
2 lb a.i.
(Kerb 50-W)
4 lb
24
60
WSSA MODE-OF-ACTION GROUP NUMBER1: 3
COMMENTS: Apply to weed free soil surface after transplanting or placing crowns. Sprinkler irrigation or rainfall is necessary to activate the herbicide (within 72 hrs for best results).
C.
SETHOXYDIM
0.1875–0.46875 lb a.i.
(Poast)
1–2.5 pt
12
7
WSSA MODE OF ACTION GROUP NUMBER1: 1
COMMENTS: Apply to small, rapidly growing seedling annual grasses or perennial grasses that are not under stress in 10–20 gal water plus a crop oil concentrate at the rate of 1 qt/acre. Rates dependent on grass size and species. Perennials often require more than one treatment. Follow label instructions regarding the use of adjuvants.
ESTABLISHED PLANTINGS
Before weeds emerge
A.
FLUMIOXAZIN
3.06 oz a.i.
(Chateau SW)
6 oz
12
NA
WSSA MODE OF ACTION GROUP NUMBER1: 14
COMMENTS: In perennial artichokes, apply in a single application after cutback for mature plants.
B.
PRONAMIDE
2–4 lb a.i.
(Kerb 50-W)
4–8 lb
24
60
WSSA MODE OF ACTION GROUP NUMBER1: 3
COMMENTS: Apply to weed-free soil surface. Sprinkler irrigation or rainfall is necessary to activate the herbicide (within 72 hrs for best results). Do not make more than 2 applications per season (one to the artichoke row and one to the untreated soil surface between the artichoke rows after the ditching operation is completed). Do not apply more than 4 lb a.i./acre to established artichokes or more than 2 lb a.i./acre to newly transplanted artichokes broadcast application.
Herbicides with both preemergence and postemergence activity
A.
DIURON*
1.6–3.2 lb a.i.
(Karmex DF)
2–4 lb
12
0
(Direx 4L)
1.6–3.2 qt
12
0
WSSA MODE-OF-ACTION GROUP NUMBER1: 7
COMMENTS: Do not use on first year plantings. Soils should have greater than 2% organic matter. Apply as a band or broadcast treatment to weed free beds or beds with small annual weeds as a directed spray to minimize crop contact. Considered to be a ground water contaminant and requires a use permit within Ground Water Protection Areas.
B.
OXYFLUORFEN
1–1.5 lb a.i.
(Goal 2XL)
4–6 pt
24
5
(GoalTender)
2–3 pt
24
5
WSSA MODE-OF-ACTION GROUP NUMBER1: 14
COMMENTS: Use as a directed spray to avoid contact with artichoke leaves. Allow at least 60 days after transplanting or harvest prior to spray. Do not apply more than 1.5 lb a.i./acre per season. Do not apply before Oct 1 or after Feb 15 (Feb 1 in the Coachella Valley).
C.
PARAQUAT*
0.6–1 lb a.i.
(Gramoxone SL 2.0)
2.5–4 pt
24
1
WSSA MODE-OF-ACTION GROUP NUMBER1: 22
COMMENTS: COMMENTS: Apply as directed spray to the plant beds or winter ditches. Applications can be continued through bud production. Apply in 20—100 gal water/acre. Do not exceed 2 lb a.i./acre per year or 3 applications per year. Can be mixed with oxyfluorfen to enhance efficacy. When pesticides are used in tank mixes, observe all directions for use on crops, rates, dilution ratio, precautions, and limitations that appear on the labels of all products used in the mixture.
After weeds emerge
A.
CLETHODIM
0.07–0.12 lb a.i.
(Select Max)
9–16 fl oz (annual grass)
12–16 fl oz (perennial grass)
24
5
WSSA MODE-OF-ACTION GROUP NUMBER1: 1
B.
HALOSULFURON-METHYL
0.75–1.5 oz a.i.
(Sandea)
1–2 oz
12
5
WSSA MODE-OF-ACTION GROUP NUMBER1: 2
COMMENTS: Apply Sandea uniformly with ground equipment in a minimum of 15 gallons of water per acre. Apply as a broadcast application to the ground on either side of the row and winter ditches while avoiding crop foliage. Row Middle: Apply Sandea between rows of perennial artichokes for the control of listed broadleaf weeds. Applications should be made when oxalis is in full bloom. Avoid contact of the herbicide with the planted crop. Application of Sandea may cause significant, temporary stunting and delay maturity of artichokes if sprayed directly. For best results, use a nonionic surfactant with applications. See label for rotational crop information.
C.
SETHOXYDIM
0.1875–0.46875 lb a.i.
(Poast)
1–2.5 pt
12
7
WSSA MODE-OF-ACTION GROUP NUMBER1: 1
COMMENTS: Apply October 1 to February 15 after completion of the ditching operation to annual grass or perennial grass seedlings that are not under stress. Apply in 10–20 gal water plus a crop oil concentrate at the rate of 1 qt/acre. Rates dependent on grass size and species. Perennials often require more than one treatment. Follow label instructions regarding the use of adjuvants.
‡
Restricted entry interval (REI) is the number of hours (unless otherwise noted) from treatment until the treated area can be safely entered without protective clothing. Preharvest interval (PHI) 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
1
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 group numbers are useful in planning mixtures or rotations of herbicides with different modes of action.
NA
Not Applicable.
Text Updated: 02/20
Treatment Table Updated: 02/20