Vegetable Production Guide

Carrots
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Table 1 Carrot Weed Control

This section was updated - 12 January 2017

Table 1 Carrot Weed Control

 

Product

Rate

PHI*

Comments

Pre-plant Incorporation

Bonanza 480

(trifluralin)

Group 3
1.25 to 2.3 L/ha
(500 to 900 mL/acre)

Apply in a minimum of 100 L/ha (40 L/acre) of water at 275 kPa
N/A
  • Rates vary with soil type, see label for detail.
  • Controls seedling grasses and some broadleaved weeds.
  • Lady’s-thumb, nightshades, groundsel, shepherd’s-purse, cudweed and mustards are not controlled.
  • Use the lower rate on sandy soil, the higher rate on heavier soils.
  • Apply treatment from 3 weeks before planting and incorporate thoroughly within 24 hours to 8 to 10 cm deep.
  • Effectiveness is reduced on cold, wet soils or on mineral soils with less than 2% or greater than 15% organic matter.
  • If manure is spread prior to application ensure it has been thoroughly mixed into soil with at least 2 tillage operations prior to application.

Stale Seed Bed

Ignite 15 SN


(glufosinate ammonium)

Group 10
2.7 to 5.0 L/ha
(1.1 to 2.0 L/acre)

Apply in 110 to 330 L/ha (45 to 135 L/acre) of water at 275 to 310 kPa
N/A
  • May be used for annual grasses and broad leaf weeds.
  • Do not handle with bare hands or with leather or cloth gloves.
  • Rainfall within 4 hours may reduce effectiveness.
  • See section on stale seed bed technique (Chapter 6 of this guide).
  • Do not enter treated area for 12 hours.

Pre-emergence

Gesagard 480SC


(prometryne)

Group 5
Sandy Soils: 3.75 L/ha
(1.5 L/acre)

Loams: 4.58 L/ha
(1.85 L/acre)

Muck Soils: 7.08 L/ha
(2.86 L/acre)
85
  • Controls many annual broadleaved weeds and seedling grasses, but not atrazine-resistant pigweed, lamb’s-quarters and groundsel.
  • For best results use on moist soils.
  • One application per season.
  • Only replant treated areas with crops on the label if planting in the same season.
  • Apply soon after planting and before emergence.
  • Do not apply at or near the time of emergence.
  • Apply in 200 to 1000 L/ha (80 to 405 L/acre) of water at 200 to 300 kPa.
  • Do not enter treated area for 12 hours.

Lorox L


(linuron)

Group 7
1.1 to 3.4 L/ha
(0.4 to 1.3 L/acre)

Apply in 225 to 335 L/ha (90 to 135 L/acre) of water
N/A
  • Severe damage may result if pre-emergence application is followed by unusually heavy rains.
  • Apply as a single broadcast spray at least 1 cm deep after planting but before emergence.
  • Do not apply more than 2.25 L/ha (0.9 L/acre) if following with a post-emergence treatment of Lorox L.  Check label for pre-emergence plus post-emergence use directions.
  • Do not replant treated areas to other crops within 4 months after last application.
  • Crop injury may result from pre-emergence application of the higher rate.
  • Do not use on coarse-textured soils, containing 2% or less organic matter.
  • Will not control atrazine resistant weeds.

Post-Emergence

Guardsman/ Agricultural Weedkiller No. 1


(mineral spirits)
For whole field treatments: 600 to 800 L/ha (242 to 324 L/acre)

For row treatments: 300 to 400 L/ha (120 to 160 L/acre)
30
  • Apply when plants are in the 2 to 4 leaf stage and before weeds are 10 cm high.
  • Controls redroot pigweed, lamb’s quarter, purslane and annual grasses.
  • Pineappleweed and wormseed mustard are not controlled consistently.
  • Crop damage may result if sprays are applied in hot, dry weather, or when plants are wet with rain or dew.
  • Note: Other solvents may cause crop damage.

Select

(clethodim)

0.19 to 0.38 L/ha                   (75 to 155 mL/acre)

Apply in 110 L/ha (45 L/acre) of water at 275 kPa

30
  • Apply post-emergence of weeds and crop.
  • Controls annual grasses and suppresses quackgrass at the 2 to 6 leaf stage.
  • Use only with the adjuvant Amigo at 0.5 to 1.0% v/v.
  • Apply early, prior to tillering.
  • Repeat using a 14 day interval.
  • Maximum of 2 applications per year.
  • Do not apply more than 0.38 L/ha (155 mL/acre) per crop season.
  • Allow 4 days after treatment before applying any chemical not listed on this label.
  • Do not enter treated area for 12 hours.
  • Group 1 herbicide.

Centurion

(clethodim)

Excel Super


(fenoxaprop-p-ethyl)

Group 1
670 mL/ha
(270 mL/acre)

Apply in at least 110 L/ha (45 L/acre) of water at 275 kPa
38
  • Apply at the 1 to 6 leaf stage of seedling grasses.
  • Controls foxtail, barnyard grass, crabgrass, fall panicum, Proso millet and old witch grass.
  • Do not apply any other pesticide, or chemical 4 days before or after applying Excel Super.
  • Does not control quackgrass, sedges, or other pernnial grasses.

Lorox L


(linuron)

Group 7
2.25 to 4.5 L/ha
(0.9 to 1.8 L/acre)

Apply in 225 to 335 L/ha (90 to 135 L/acre) of water at 175 to 275 kPa
N/A
  • For carrots not treated with Lorox L pre-emergence, apply when crop has two or more fully developed true leaves (8 to 15 cm tall).
  • For carrots treated with Lorox L pre-emergence, follow with a post-emergence application provided treatments are at least two weeks apart (Check label for pre-emergence plus post-emergence use directions). 
  • Controls annual grasses and broadleaf weeds.
  • Will not control atrazine resistant weeds.
  • Use the lower rate on small seedling weeds and the higher rate on larger established weeds.
  • Apply before annual grasses are 5 cm tall and before broadleaved weeds reach 15 cm.
  • To avoid crop injury, temperature should be below 32 C and spray pressure should not exceed 275 kPa
  • If unusually heavy rains follow application, severe injury may result.
  • Do not use on sandy soils with less than 2% organic matter.
  • Do not replant treated areas to other crops within 4 months after last application.
  • Allow 2 weeks between oil application and Lorox.

Venture L


(fluazifop-P-butyl)

Group 1
Barnyard Grass (2 to 5 leaf): 0.8 L/ha (320 mL/acre)

Proso Millet (2 to 5 leaf): 1.0 L/ha (400 mL/acre)

Foxtails (2 to 4 leaf): 1.4 L/ha (560 mL/acre)

Quackgrass (3 to 5 leaf): 2.0 L/ha (800 mL/acre)
50
  • Annual bluegrass and broadleaved weeds are not controlled.
  • Apply in 50 to 200 L/ha (20 to 80 L/acre) of water at 200 to 300 kPa.
  • Apply when crop is 10 cm in height or less.
  • Warning: Women capable of bearing children should avoid exposure to Venture.

Dual II Magnum


(S - metolachlor)

Group 15
1.2 to 1.5 L/ ha
(500 mL to 600 mL/ acre)

Apply in 150 to 300 L/ha (60 to 120 L/acre) of water
30
  • Apply to crop at 3 to 5 leaf stage and weeds prior to 2-leaf stage.
  • Controls labelled weeds including nightshade, foxtail and barnyard grass.
  • Make only one application per year.
  • Do not re-enter for 12 hours.
  • Do not tank mix with fluid fertilizers, oils, oil concentrates or surfactants.
  • Rain is required within 10 days of application, or a shallow cultivation.
  • Do not apply to soils with less than 1% or more than 10% organic matter.

Sencor 75 DF


(metribuzin)

Group 5
190 g/ ha
(77 g/ acre)

Apply in 150 to 300 L/ha (60 to 120 L/acre) of water at 150 to 275 kPa 
60
  • Use only on carrots treated pre-emerge with linuron herbicide.
  • Controls annual broadleaf weeds less than 4 cm in height including common chickweed, lamb's quarters and wild mustard.
  • Does not control triazine resistant weed biotypes.
  • Apply when the 4th leaf is paritially expanded for most of the carrot plants.
  • Repeat application can be made when the 5th leaf of most of the carrot plants is partially expanded.
  • Do not tank mix with fluid fertilizers, oils, oil concentrates or surfactants.
  • May be applied when crop is wet with dew, but control is reduced if applied within 6 hours of a rainfall.
  • To improve coverage, spray boom may be rotated forward by 45°.
  • First use should be applied to a limited area of each cultivar to determine crop tolerance before adoption as a field practice.
  • It may be necessary to delay harvest of sensitive cultivars treated with Sencor 75 DF.
  • Do not apply to stressed plants.
  • 3 days of sunny weather should follow cloudy, cool weather before applying. 
  • On sunny days, application should be made in the afternoon or early evening.
  • Do not apply on coarse soils with less than 2%organic matter.
  • Rotation crops including onions, celery, peppers, cole crops, lettuce, spinach, table beets, turnips, pumpkin, squash, cucumbers and melons may be injured if planted into soil treated with Sencor 75 DF during the year of application or the following crop year. 
  • Fall-seeded cover crops including wheat, oats and rye may be injured when planted within the same season as the application of Sencor 75 DF
  • Do not re-enter for 12 hours.

Aim EC

(carfentrazone-ethyl)

Group 14

37 to 117 mL/ha
(15 to 47 mL/acre)

Apply in 100 L/ha (40 L/acre) of water
1
  • Controls annual weeds.
  • Must be applied using hooded sprayers to weeds between the rows of the emerged crop.
  •  Use an adjuvant such as Agral 90 or Agral-Surf at 0.25% v/v (0.25 L/100 L of spray solution) or Merge at 1% v/v (1 L/100 L of spray solution).
  • PRECAUTION:  crop injury will occur when spray drift is allowed to come in contact with green stem tissue or leaves.
  • Apply only once per growing season.
Poast Ultra plus Merge at the following rates: 49
  • Apply when annual weeds are in the 1 to 6 leaf stage, and when quackgrass is in the 1 to 3 leaf stage.
  • Apply in 100 to 200 L/ha (40 to 80 L/acre) of water.
  • Pressure varies with water volume, see label for detail.
  • Annual bluegrass is not controlled.
  • Group 1 herbicide.
  • Do not enter treated area for 12 hours.
  • There is a 30 day plant back restriction on crops not found on the label.
 

Poast Ultra

Merge

Annual grasses (incl volunteer) cereals) 320 mL/ha
(130 mL/ac)
0.5-1.0 L/ha
(0.2-0.4 L/ac)
Annual grasses & quackgrass suppression 470 mL/ha (190 mL/ac) 0.5-1.0 L/ha (0.2-0.4 L/ac)
Quackgrass 1.1 L/ha (445 mL/ac) 1.0-2.0 L/ha (0.4-0.8L/ac)
*PHI = Pre-harvest interval
BUFFERS – Refer to product label for buffer requirements. See also Pesticide Regulations and Safety section of this guide.
PESTICIDE GROUP DETAILS – see Pesticide Toxicity Table of this guide.

 

Viewing Section 9 of 11