Asparagus

Controls for All Weeds

Description

Before establishing an asparagus planting, reduce perennial weeds in the area to be planted with systemic broad-spectrum herbicides. Herbicide options are limited in the planting year.

After the first year of establishment, a typical weed control program in asparagus includes a preemergence herbicide with a long residual applied before asparagus emerges. If needed, a preemergence herbicide may be applied again after harvest is finished and a clean mowing.

Postemergence herbicides may be applied before asparagus emergence or during or after the harvest season. Some require directed or shielded spray applications to avoid spraying asparagus.

It is important use herbicides with different modes of action from year to year with this perennial crop to avoid buildup of weed species not controlled by a particular mode of action.

For specific weeds controlled by each herbicide, check the Relative Effectiveness of Herbicides for Vegetable Crops table.

Rates provided in the recommendations below are given for overall coverage. For a banded treatment, reduce amounts according to the portion of acre treated.

Non-Pesticide

Application Notes

Good weed control in the planting year is especially important. Multivators, tines, rolling cultivators, and flame weeders work well before emergence of asparagus, but it is important to avoid damaging crowns when cultivating. Cultivate row-middles and hand-hoe after emergence. Flame weeders can also be used after clean harvest or mowing. Once established, straw mulch can be applied any time, but is easier for picking when applied after final harvest.

Pesticide

Application Notes

Available as both amine and choline formulations. Use 3-4 pts. per acre of liquid formulations with 3.8 lbs. per gal. acid equivalent. Apply before, during, or after the harvest season. During harvest season apply immediately after cutting. Discard deformed spears. Use drop nozzles for treatments after harvest to avoid spraying fern. Wait at least 30 days between applications.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

During asparagus harvest after cutting; After final asparagus harvest, before new growth; After final asparagus harvest and new growth; When crop is dormant

Herbicide Placement and Application Type

Between rows, crop protected from spray; Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

48-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

3-day.

Signal Word

warning

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


2,4-D:

Do not apply or allow to drift to plants that are flowering, or water puddles, except when the application is made between sunset and midnight if allowed by the pesticide label and regulations.

UC Davis Bee Precaution EffectsInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) detailing whether the pesticide is known to accumulate in honey bee brood or is known to be toxic to other bees.</p>

2,4-D:

Toxic to honey bee brood.

Application Rate
0.5-1.92 fl. oz. per acre.
Application Notes

Include 0.5 pt. NIS or 0.25-0.5 gals. COC per 25 gals. of spray solution. Broadcast after spear harvest. Emerged asparagus will be injured. Do not exceed 3.8 fl. oz. per acre per season. Wait at least 20 days between applications.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

During asparagus harvest after cutting; After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

5-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


carfentrazone:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
3-7.7 fl. oz. per acre.
Application Notes

Apply in spring before spears emerge after mowing, disking, or tilling; after final harvest; or both. For postharvest applications use drop nozzles or other equipment that will minimize contact with crop. Adding COC or NIS (alone or with UAN or AMS) will improve emerged weed control and increase crop injury risk in postharvest applications. Do not exceed 2 applications per year, or 7.7 fl. oz. per acre per year.

Herbicide Timing Relative To Weeds

Preemergence; Postemergence

Herbicide Timing Relative to Crops

After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Between rows, crop protected from spray; Broadcast, surface application

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Application Rate
6 oz. per acre of Chateau SW or 6 fl. oz. per acre of Chateau EZ.
Application Notes

Established plantings only. Apply to dormant asparagus at least 2 weeks before spears emerge. Crop injury may result if asparagus is not dormant. May be tank-mixed with paraquat to control emerged weeds. Or, apply after final harvest for the season before fern emerges. Do not exceed 6 oz. per acre per growing season.

Herbicide Timing Relative To Weeds

Preemergence

Herbicide Timing Relative to Crops

After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, surface application

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

Yes, see label

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


flumioxazin:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
0.5-1.0 pt. per acre.
Application Notes

Apply in 40-60 gals. of water per acre immediately after cutting. Discard crooked spears at harvest. Clarity can injure nearby broadleaf crops and garden plants. Maximum 1 pt. per acre per year.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

During asparagus harvest after cutting

Herbicide Placement and Application Type

Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

24-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

1-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


dicamba:

No bee precaution, except when required by the pesticide label or regulations.

Application Notes

Use 2EC formulations at 6-8 fl. oz. per acre with 1 qt. of COC per 25 gals. of spray solution (1% v/v). Use Select Max at 9-16 fl. oz. per acre with 8 fl. oz. of NIS per 25 gals. of spray solution (0.25% v/v).

Spray on actively growing grass. Wait at least 14 days between applications.

Do not exceed 32 fl. oz. of 2EC formulations or 64 fl. oz. of Select Max per acre per season.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

After crop seeding before emergence; During asparagus harvest after cutting; After final asparagus harvest, before new growth; After final asparagus harvest and new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, over top of crop and weeds; Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

24-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

1-day.

Signal Word

warning

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain crops, see label

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


clethodim:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
8-10.7 fl. oz. per acre.
Application Notes

Apply Spur before or during harvest. May cause some crooking of spears. Controls Canada thistle, marestail, mayweed, nightshade, plantain, smartweeds. Do not exceed 10.7 fl. oz. per acre per year. Avoid application 2 years in succession.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

After crop seeding before emergence; During asparagus harvest after cutting; After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour.

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

2-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Application Notes

Established plantings only. Do not apply to young plants during the first year. Use 80DF formulations at 1-4 lbs. per acre, and do not exceed 6 lbs. per acre per season. Use 4L formulations at 0.8-3.2 qts. per acre and do not exceed 4.8 qts. per acre per season. Use lower rates on light-colored soils with less than 2% organic matter. Apply after tillage or chopping fern in the spring and again after harvest, if necessary. See product label for split application rates. 6-8 weeks of residual activity. RUP in Michigan only.

Herbicide Timing Relative To Weeds

Preemergence

Herbicide Timing Relative to Crops

After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, surface application

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Signal Word

caution

Restricted Use Pesticide (RUP)Info Icon
<p>Restricted Use Pesticides (RUPs) require certification through State Departments of Agriculture to buy and apply.</p>

yes

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

Yes, see label

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


diuron:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
1.33-2.0 pts. per acre.
Application Notes

Illinois, Indiana, Michigan, and Minnesota 24c label only. Apply before asparagus and weeds emerge in spring or after the harvest season. Needs moisture for activation. Do not exceed 1 application per crop.

Herbicide Timing Relative To Weeds

Preemergence

Herbicide Timing Relative to Crops

After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, surface application

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

24-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

16-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


s-metolachlor:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
8-12 fl. oz. per acre.
Application Notes

Include 1-2 pts. of COC or 0.5-1 pt. of NIS per 25 gals. of spray solution. Spray on actively growing grass. Rates may be doubled if asparagus will not be harvested for 12 months. Wait at least 14 days between applications. Do not exceed 48 fl. oz. per acre per season on bearing asparagus.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

After crop seeding before emergence; After crop emergence or transplanting; During asparagus harvest after cutting; After final asparagus harvest, before new growth; After final asparagus harvest and new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, over top of crop and weeds; Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

1-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

Yes, see label

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


fluazifop-P:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
0.75-3.75 lbs. acid equivalent (ae) per acre.
Application Notes

Use formulations containing 3 lbs. ae per gal. (4 lbs. isopropylamine salt per gal.) at 1-5 qts. per acre, or formulations containing 4.5 lbs. ae per gal. (5 lbs. potassium salt per gal) at 0.66-3.3 qts. per acre. Apply to emerged weeds at least 7 days before spears emerge or immediately after last harvest. Use low rate for annuals and higher rates for perennials.

See label for suggested application volume and adjuvants. If spears are allowed to regrow, delay application until ferns have developed and apply as a directed or shielded spray. Contact of the spray with asparagus fern may result in crop injury.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

Before crop seeding; Before crop transplanting; After crop seeding before emergence; After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Between rows, crop protected from spray; Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

4-hour to 12-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

14-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Yes

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


glyphosate:

Do not apply or allow to drift to plants that are flowering, or water puddles, except when the application is made between sunset and midnight if allowed by the pesticide label and regulations.

UC Davis Bee Precaution EffectsInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) detailing whether the pesticide is known to accumulate in honey bee brood or is known to be toxic to other bees.</p>

glyphosate:

Toxic to honey bee brood.

Application Rate
2-4 lbs. per acre.
Application Notes

Established crowns: Apply before spears emerge, before cutting season or immediately after cutting, or as directed spray in ferns.

New planted crowns: To control small emerged weeds apply 1-2 lbs. per acre, up to 2 applications when ferns are 6-18 inches tall.

Newly seeded crops: Apply a 1-inch band of activated charcoal over the row at planting, then apply Lorox. Use charcoal at 300 lbs. per acre of actual area sprayed, which is equivalent to 15 lbs. per acre of crop with a 20-inch row-spacing. Or, use the low rate of Lorox when ferns are 6-18 inches tall and weeds are less than 4 inches tall.

Do not use on sand, loamy sand, or soils with less than 1% organic matter. Maximum 4 lbs. or 3 applications per acre per year.

Herbicide Timing Relative To Weeds

Preemergence; Postemergence

Herbicide Timing Relative to Crops

After crop seeding before emergence; After final asparagus harvest, before new growth; After final asparagus harvest and new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, surface application; Broadcast, over top of crop and weeds; Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

24-hour to 8-day.

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

1-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


linuron:

No bee precaution, except when required by the pesticide label or regulations.

Application Notes

Established plantings only. Do not apply to young plants during first year. Use 75DF formulations at 0.6-2.6 lbs. per acre. Use 4F formulations at 2-4 pts. per acre. See product label for split application rates. Use low rate if combined with diuron. 6-8 weeks residual activity. Two sprays necessary for seasonlong sandbur control. Do not exceed 2.6 lbs. or 4 pts. per acre per year.

Herbicide Timing Relative To Weeds

Preemergence; Postemergence

Herbicide Timing Relative to Crops

After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, surface application; Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

14-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


metribuzin:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
2.5-4 pts. per acre.
Application Notes

Include 1 qt. of COC, or 4-8 fl. oz. of NIS per 25 gallons of spray solution. Apply before crop emergence or after last harvest before fern regrows.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

Before crop seeding; Before crop transplanting; After crop seeding before emergence; After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12 to 24-hour.

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

6-day.

Signal Word

danger

Restricted Use Pesticide (RUP)Info Icon
<p>Restricted Use Pesticides (RUPs) require certification through State Departments of Agriculture to buy and apply.</p>

yes

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

Yes, see label

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Very Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


paraquat:

Do not apply or allow to drift to plants that are flowering, or water puddles, except when the application is made between sunset and midnight if allowed by the pesticide label and regulations.

UC Davis Bee Precaution EffectsInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) detailing whether the pesticide is known to accumulate in honey bee brood or is known to be toxic to other bees.</p>

paraquat:

Toxic to honey bee brood.

Application Rate
2.4-8.2 pts. per acre.
Application Notes

Use formulations with 3.8 lbs. active ingredient per gallon. Apply at least 14 days before first harvest and prior to spear emergence. If spears are present, remove before application. On sandy soil use no more than 2.4 pts. per acre. Do not apply to newly seeded asparagus during first year.

Herbicide Timing Relative To Weeds

Preemergence

Herbicide Timing Relative to Crops

When crop is dormant

Herbicide Placement and Application Type

Broadcast, surface application

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

24-hour.

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

14-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


pendimethalin:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
1-1.5 pts. per acre.
Application Notes

Include 1 qt. COC per acre. Spray on actively growing grass. Use high rate on quackgrass. Do not exceed 5 pts. per acre per season.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

After crop seeding before emergence; After crop emergence or transplanting; During asparagus harvest after cutting; After final asparagus harvest, before new growth; After final asparagus harvest and new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, over top of crop and weeds; Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

1-day.

Signal Word

warning

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


sethoxydim:

Do not apply or allow to drift to plants that are flowering, or water puddles, except when the application is made between sunset and midnight if allowed by the pesticide label and regulations.

Application Rate
12.6 fl. oz. per acre.
Application Notes

Include 1 qt. of COC per 25 gallons of spray solution. Apply after final harvest for the year. Controls bindweed, Canada thistle, barnyardgrass, large crabgrass. Do not exceed 1 application per year.

Herbicide Timing Relative To Weeds

Postemergence

Herbicide Timing Relative to Crops

After final asparagus harvest and new growth

Herbicide Placement and Application Type

Broadcast, over top of crop and weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


quinclorac:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
0.5-1.5 oz. per acre.
Application Notes

Apply before, during, or after harvest. Drop nozzles and using COC or NIS are recommended for applications after harvest. For first year transplants do not apply sooner than 6 weeks after fern emergence. Do not exceed 2 applications per crop cycle, or 2 oz. per acre per 12-month period. Has residual soil activity. Effective on nutsedge.

Herbicide Timing Relative To Weeds

Preemergence; Postemergence

Herbicide Timing Relative to Crops

After crop seeding before emergence; During asparagus harvest after cutting; After final asparagus harvest, before new growth; After final asparagus harvest and new growth; When crop is dormant

Herbicide Placement and Application Type

Between rows, crop protected from spray; Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

1-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


halosulfuron:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
0.62-1.5 lbs. per acre.
Application Notes

Established crowns or direct-seeded crops only. Do not use on sandy soil or on soil with less than 1% organic matter. Established crowns: Apply in spring after cutting fern and prior to spear emergence. May also be applied after a clean cutting. Seeded crops: At planting spray activated charcoal at 300 lbs.per acre of actual area treated in a 1-inch band over the row (equivalent to 15 lbs. per acre of crop with 20-inch row spacing), then apply Sinbar. Do not plant other crops within 2 years of application. 8-12 weeks residual activity.

Herbicide Timing Relative To Weeds

Preemergence; Postemergence

Herbicide Timing Relative to Crops

After final asparagus harvest, before new growth; When crop is dormant

Herbicide Placement and Application Type

Broadcast, surface application

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

5-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

Application Rate
2.5-5 lbs. per acre.
Application Notes

Established plantings only. Do not apply within 12 months of planting. Apply preemergence to soil free of weeds and debris.

Herbicide Timing Relative To Weeds

Preemergence

Herbicide Timing Relative to Crops

When crop is dormant

Herbicide Placement and Application Type

Broadcast, surface application

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

14-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

No

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


norflurazon:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
4.5-12 fl. oz. per acre.
Application Notes

Michigan only - applicators must have a supplemental label. Established plantings only. Apply in spring before crop emerges. Use low rate on light soil. Do not use on soils with less than 1% organic matter. Do not exceed 1 application and 12 fl. oz. per acre per season.

Herbicide Timing Relative To Weeds

Preemergence

Herbicide Timing Relative to Crops

When crop is dormant

Herbicide Placement and Application Type

Broadcast, surface application

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

14-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Intermediate Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


sulfentrazone:

No bee precaution, except when required by the pesticide label or regulations.

Application Notes

Established plantings only. Use 4EC formulations at 2-4 pts. per acre. Use 10G formulations at 10-20 lbs. per acre. Use lower rates on coarse soils. Apply and incorporate 1-2 inches early in the spring when spears are at least 4 inches below soil surface. See product label for split application instructions. 4-6 weeks of residual activity.

Herbicide Timing Relative To Weeds

Preemergence

Herbicide Timing Relative to Crops

When crop is dormant

Herbicide Placement and Application Type

Broadcast, incorporate

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

12-hour

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


trifluralin:

No bee precaution, except when required by the pesticide label or regulations.

Application Rate
116-172 fl. oz. per acre.
Application Notes

Broadcast 14 days before emergence. Do not apply to seedlings or first-year transplants.

Herbicide Timing Relative To Weeds

Preemergence; Postemergence

Herbicide Timing Relative to Crops

After crop seeding before emergence

Herbicide Placement and Application Type

Broadcast, surface application; Broadcast, over top of weeds

Restricted-Entry Interval (REI)Info Icon
<p>Read and follow the label directions. Post areas or give oral warnings that areas have been treated to warn workers not to enter until the Restricted-Entry Interval (REI) has elapsed as required by the label.</p>

24-hour.

Pre-Harvest Interval (PHI)Info Icon
<p>Read and follow the label directions. Do not harvest until the PHI has elapsed as required by the label.</p>

14-day.

Signal Word

caution

Chemigation UseInfo Icon
<p>Some pesticides are explicitly labeled for chemigation. Some pesticide labels imply chemigation use (silent labels) or explicitly restrict it. Always double check the label.</p>

Certain systems or crops, see label

Greenhouse UseInfo Icon
<p>Some pesticides are explicitly labeled for greenhouses. Some pesticide labels imply greenhouse use (silent labels) or explicitly restrict it. Always double check the label.</p>

Silent

Respirator UseInfo Icon
<p>Some pesticides require specific respirators for mixing, loading, and applying. Always double check the label.</p>

No

Leaching RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

Low Risk

Runoff RiskInfo Icon
<p>These leaching/runoff potential ratings are from the Pesticide Leaching Potential (PLP) and Pesticide Adsorbed Runoff Potential (PARP) datasets in the NRCS WIN-PST Pesticide Properties Database at <a href="http://go.usa.gov/Kok">http://go.usa.gov/Kok</a></p>

High Risk

UC Davis Bee Precaution RankInfo Icon
<p>This is from the UC Davis Bee Precaution Ratings (<a href="https://www2.ipm.ucanr.edu/beeprecaution/">https://www2.ipm.ucanr.edu/beeprecaution/</a>) which recommend the following actions based on the LD50 values and the potential exposure routes of pesticides. The rating is based on the individual active ingredient(s) posing the greatest hazard to bees.</p>


pendimethalin:

No bee precaution, except when required by the pesticide label or regulations.


metribuzin:

No bee precaution, except when required by the pesticide label or regulations.

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Midwest Vegetable Production Guide

The Midwest Vegetable Production Guide for Commercial Growers is a collaboration of land-grant universities from eight states. It provides vegetable production information that is valid in the participating states for the current year. This includes fertility, variety, cultural, and pest management recommendations. The online guide was supported by MSU Extension, and donations from the Michigan Vegetable Council, the Indiana Vegetable Growers Association, the Kansas Vegetable Growers Association, and by the Crop Protection and Pest Management Program [grant no 2021-70006-35450] from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

The management practices, products, and cultivars discussed in this publication are the research and experience-based recommendations of the institutions associated with the contributing editors and authors. These recommendations are not exhaustive and other practices and products not mentioned in this guide might also be effective. Read and follow label instructions before using any pesticide product.

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