2017 Crop Protection Guide for Tree Fruits in Washington

Chemical Weed Control

Friday, January 19, 2018

Temporary Weed Control on Pome Fruit

See General Recommendations for guidelines on table use. Read all product labels carefully.


 Broadleaf
weeds
Grass
and/or
broadleaf
weeds
REIPHIModeMRL

Product

Except where noted, rates are amount per acre (active ingredient per acre) 
Firestorm
paraquat
--
1.7-2.7 pt (0.64-1.0 lb AI)

24 h

NL

22
 
Gramoxone Inteon
paraquat
--
2.5-4 pt (0.63-1.0 lb AI)

24 h

NL

22
 
Rely 280
glufosinate-ammonium; apples only
--
1.28-2.56 qt (0.75-1.5 lb AI)

12 h

14 d

10
 
Saber
2,4-D

3 pt (1.425 lb AI)
--
48 h

14 d

4
 
Venue
pyraflufen-ethyl

1-4 fl oz (0.0013-0.0053 g AI)
--
12 h

0 d

14
 
glyphosate -- 1-3.0 qt (--)4 h1 d9  


Firestorm: WSSA Group 22: photosystem I electron diverter

Has the same active ingredient, but at a higher concentration, than Gramoxone, so note the lower use rates.  For other details, see entry for Gramoxone Inteon.

Gramoxone Inteon: WSSA Group 22: photosystem I electron diverter

Foliage applied, contact herbicide used to control annual broadleaf and grass weeds and to suppress perennial weeds. Apply as a directed spray. May be used at any time, but most effective when weeds are no more than 4–6 inches tall and growing actively. Thorough spray coverage is required to ensure control.  Keep off tree foliage, fruit, and green bark. Often tank-mixed with soil residual herbicides to control established weeds. Paraquat is corrosive to aluminum. This is a restricted-use herbicide. Use this product only if you carefully read and follow PPE directions on the lable. Use a full face shield, gloves and apron when filling and mixing. Do not ingest or inhale spray mist when spraying. Grazing of livestock is prohibited.

Rely 280: WSSA Group 10: glutamine synthase inhibitor

Foliage applied, contact herbicide used to control annual broadleaf and grass weeds and to suppress perennial weeds. Apply when weeds are small and actively growing. Stressed weeds may be more difficult to control. Use rate is dependent on weed size and growth stage. Use as a directed spray. Avoid contact of spray or mist on new foliage or green shoots; only apply to trees with calloused, mature, brown bark. Thorough coverage of target weeds is essential for control. No additional surfactant is needed. Grazing of livestock is prohibited.

glyphosate: WSSA Group 9: EPSPS inhibitor

Glyphosate is a broad-spectrum, systemic herbicide. It is one of the most commonly applied herbicides and is sold under many trade names. Some of the products containing glyphosate are identical to the original product, others vary in their additives (such as wetting agents) and amount of active ingredient. The parent acid, the "active ingredient," is formulated with ammonium, potassium, or isopropylamine and varies in content per gallon from one product to another. The active ingredient is called "acid equivalent" in glyphosate products, and can range from 3 to 5 pounds per gallon, depending on the product. If you switch products, compare the acid equivalent of the two, and make rate adjustments, if necessary. Repeated use of glyphosate has led to the development of glyphosate resistance in many species common to perennial systems in the West Coast; rotate with other foliar-applied herbicides. Water quality and quantity can affect glyphosate performance; high pH, presence of cations, or dirty water can reduce efficacy. See label regarding adjuvant use. Grazing of livestock is prohibited.

Saber: WSSA Group 4: synthetic auxin

Alternate trade names: Saber, Orchard Master, Weedar 64, Opti-Amine, Amine 4 2,4-D. Kills most annual and many perennial broadleaf weeds. Apply as directed spray on weeds to point of run-off. Avoid contact with tree foliage, limbs, and trunk. Do not apply during windy periods. Do not apply to shallow or sandy soils. Best results are obtained when applied within 2 days following an irrigation and the weeds are growing actively. In sprinkler-irrigated orchards, apply only after irrigation and never to dry or bare ground. Can be absorbed by tree roots and cause serious injury if carried into the root zone by irrigation. The Gala, Fuji and Golden Delicious apple varieties appear to be more sensitive to root uptake of 2,4-D than other varieties. Reduce possible root uptake by applying 2,4-D at a time of season when frequent irrigation is not necessary. Do not apply to trees established in orchard less than 1 year. Do not apply during bloom. Do not make more than two applications per season. Do not harvest within 14 days of application. Grazing is prohibited.

Venue: Group 14: protoporphyrinogen oxidase (PPO) inhibitor

A contact herbicide that is active on annual broadleaf weeds. Use as a directed spray when the weeds are less than 4 inches tall or 3 inches across. Thorough coverage is required for control. Apply during the dormant season and prior to bloom. Addition of a crop oil concentrate or non-ionic surfactant will enhance control. Keep off green stems and foliage, will burn off young green crown and root suckers. Use lower rates for small weeds and higher rate for larger weeds. Tank mixing can increase the weed spectrum that is controlled. 


 

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