January 2015


Use dormant-stem applications to keep spray crews busy during the winter months

The arrival of winter weather doesn’t mean herbicide application crews need to shut down for the season. Unwanted trees and brush don’t take an off-season, even though there is a tendency for crews to slow or shut down when vegetation goes dormant.

Dormantstem4_250One option to stay on top of unwanted brush is to use dormant-stem treatments that can be made later in the fall, throughout the winter months and even into spring when many crews have put their application equipment up until the next growing season. These treatments can not only extend the application season but also keep good, productive crews working.

Opportunity for low-volume backpack treatments

Used in the winter to early spring time period, this dormant-stem treatment allows the application season for brush control to begin at fall leaf senescence and continue until early bud break. This timing offers the opportunity for a reallocation of work crews from late to early in the season when most crews are shutting down for the season.

Treatments are recommended between fall leaf senescence and up to 25 percent plant leafout. The application technique is similar to foliar applications except there is no foliage to spray (except with evergreen species such as conifers, which are treated the same as dormant deciduous trees).

For low-volume backpack treatments, the recommended tank mixes are listed in the charts below.

These rates are recommended for low to medium brush density (up to 1,500 stems per acre) at heights of 5 to 8 feet tall or shorter and are applied at total volumes between 6 to 30 gallons per acre of mixed solution. Rates will vary by target vegetation and brush density. Always read and follow all labeled rate restrictions.

It’s important to treat at least 75 percent of the crown of the plant. This means droplets need to be scattered over that portion of the crown to ensure the terminal is covered. Orient the spray pattern to align with the target brush structure, as this can increase the inception by the target stems.

Excellent control with added benefits
Utilities using these treatments have seen anywhere from 85 percent to 90 percent control on hardwoods such as maple and oak, as well as conifers such as hemlock and pine. Another benefit of the selective mix is the selectivity to grasses, lilies, ferns and monocots, as well as providing for early spring greenup of desirable plants. For roadside managers, the treatment also has exhibited control on broadleaf weeds in spring.

Dormantstem1_250In addition, depending on application timing and species, many targeted plants simply don’t leaf out in the spring following application so there is no visible brownout effect (except on evergreen species), reducing public visibility and potential complaints. Many evergreen species brown out slowly instead of rapidly due to reduced plant growth during the dormant period. Also, because of the soil activity of Milestone® specialty herbicide, the treatments will provide seedling control of weeds sensitive to activity with Milestone.