Midwest Vegetable Guide - 2022 - 59

Weed Management Strategies
feet tall to adequately suppress weeds. In most
cases,additional herbicides and or mechanical control may be
required. The system should be evaluated in small areas
before it is adopted.
Refer to Examples of Integrating Cover Crops section, the
Summary of Nonchemical Weed Management Practices
table, and the Weed 'Em and Reap Part 2: Reduced Tillage
Strategies for Vegetable Cropping Systems video series found
at eorganic.org/node/3409 for additional information. The
most effective weed management system is an integrated
approach that combines many different practices. This
approach must be adaptive, aiming to prevent weed problems
or cope with any that occur.
Chemical Weed Management
Strategies
Several herbicides are often labeled for a particular crop.
Scouting your area to determine which weeds are present will
allow you to select the herbicides that will give you the best
control.
All the herbicides labeled for a crop are not necessarily listed
in this guide. If you are unfamiliar with an herbicide, conduct
a small test under your environmental conditions and cultural
practices before using the herbicide extensively.
Herbicide Labels
Always Read and Understand the Herbicide Label Before
Use. Reading the herbicide label is a very profitable use of
your time. Information on the label will direct you to the
correct uses, application methods, rates, and potential
environmental hazards of the product.
Follow label directions for the best possible control with
minimal crop injury and environmental contamination. The
label contains restrictions on use and discusses environmental
and soil conditions that affect crop injury, influence the
effectiveness of weed control, and can cause nontarget site
effects.
Do Not Use Any Herbicide Unless the Label States That It
Is Cleared for Your Particular Use and Crop. Using a
nonregistered pesticide can cause harmful residues in the
vegetable crop, which can result in crop seizure and
consumer injury. The label also states whether the herbicide
is a restricted-use or general- use pesticide. Restricted-use
pesticide labels contain a statement that the products are
restricted and that only licensed applicators can buy them and
supervise their application. The information in this
production guide is current as of the date of publication.
Watch for notices of changes in the U.S. Environmental
Protection Agency (EPA) registration of herbicides from your
state Extension service.
Herbicides for Reduced Tillage
Systems
Reduced tillage systems combat soil erosion. These systems
often include the use of glyphosate or paraquat outside the
normal growing season to control emerged weeds. Weeds
should be growing actively, and the application must be made
before the crop has emerged. If you are applying glyphosate
to control perennial weeds, apply it before the soil is
disturbed. After it is applied, glyphosate must be allowed to
translocate throughout the perennial weed for several days, or
incomplete control may result. Follow glyphosate label
directions carefully for rates and timing of applications. If
perennial weeds are not a major problem, you can eliminate
early weed flushes by applying glyphosate or paraquat to all
weeds that emerge. Plant the crop with minimal working of
the soil. Never apply glyphosate or paraquat to an emerged
crop because severe crop injury or death will occur.
Glyphosate and paraquat will control most annual broadleaf
and grass weeds. Neither herbicide has any soil residual
activity, so other weed control measures will be necessary
during the growing season. Paraquat will suppress perennials
by killing their shoots, but it does not control regrowth of
perennial weeds from rhizomes or other underground storage
organs. Glyphosate is better for controlling perennials
because it will kill shoots and translocate to destroy
underground parts. Glyphosate will only suppress some
particularly hard-to- control perennials such as bindweed,
hemp dogbane, and milkweed. To control these perennials,
high application rates, repeat applications of glyphosate
(within label guidelines), or mechanical removal may be
necessary.
Herbicide Rates and Guidelines for
Use in Vegetable Crops
All herbicide rates given in this guide are in amount of
product per broadcast acre. Adjust amounts accordingly for
banded applications. Make preemergence applications before
weeds emerge or after removing any weeds present. Make
postemergence applications after weeds have emerged.
Several materials may be used between crop rows if
appropriate steps are taken to prevent spray from contacting
the crop. Some of these materials require shielded sprayers,
while others require hooded sprayers. The herbicide
recommendations in this guide do not replace careful reading
of current herbicide labels. Re-registration of older herbicides
has affected the availability of many products. Some of the
older herbicides not re-registered are not listed in this
bulletin, but may be available, and old stocks can still be
used.
Midwest Veg Guide 2022
59
https://eorganic.org/node/3409
Midwest Vegetable Guide - 2022

Table of Contents for the Digital Edition of Midwest Vegetable Guide - 2022
