Right of Way Herbicides: Grazing, Haying and Manure Management MN PIE Recertification Training Prepared by Louanne Brooks Dow AgroSciences

Before we get started….. This presentation is not intended to be a complete review of all herbicide products labeled for rights of way use. Always read and follow all label instructions. TORDON, GARLON, MILESTONE, OPENSIGHT, DMA4 herbicides are registered trademarks of Dow AgroSciences LLC. VIEWPOINT, STREAMLINE, PERSPECTIVE, ESCORT, KRENITE herbicides are registered trademarks of DuPont. ARSENAL, HABITAT herbicides are registered trademarks of BASF Corporation.

Right 0f Way Herbicides Right of Way (ROW) Herbicides are used on sites such as roadsides, power line rights of way, railroads and pipelines to control vegetation which can interfere with the purpose of the right of way. Target species include woody and herbaceous plants. Treatments include broadcast and spot applications for either bareground or selective broadleaf control. Some of ROW products are also marketed for agricultural uses; some are strictly non-crop.

Right 0f Way Herbicides Product labels and MSDS can be found at: www.cdms.net/LabelsMsds Herbicides intended for use on rights of way should be labeled for non-crop and/or rights of way. In order for a product to be used where livestock graze, or on feed for livestock, the active ingredient must pass a series of residue tolerance tests as required by FIFRA. Therefore, some ROW products allow haying, grazing or use on feed crops; some do not. Label language varies. Read labels thoroughly to understand how to use the product when livestock may consume treated vegetation.

Example: Garlon 4 Ultra is an example of a product that refers to grazing in the general use statement: This product is labeled for non-crop, rights of way, forestry and grazed areas on these sites.

Grazing and Haying Most ROW herbicides either allow or prohibit grazing and haying. Occasionally an older product may have no label language regarding haying and grazing. The label statements for both activities usually appear close together on the label. There may be multiple statements regarding grazing and haying, at more than one location, on the label.

Right of Way Herbicides with no Grazing or Haying provisions Not all products labeled for use in rights of way allow haying or grazing following application. Products that prohibit livestock consumption include: Viewpoint Perspective Streamline Krenite: DuPont has developed and submitted data to EPA to allow use of these products for haying and grazing with the anticipation of labeling late in 2013.

ROW Herbicides that allow Grazing and Haying ( ROW Herbicides that allow Grazing and Haying (*some restrictions may apply) RESIDUAL NON-RESIDUAL Opensight Tordon Milestone Transline Habitat Arsenal Garlon Rodeo Escort XP 2,4-D

Examples of Restrictions Escort XP

Examples of Restrictions: Arsenal Powerline Follow the directions for Pasture and Rangeland when treating grazed areas on ROW Animals can graze immediately after spot treatment Do not cut hay for 7 days after spot treatments This is referred to as the “PHI” or pre-harvest interval

Examples of restrictions pertaining to lactating dairy animals Rodeo

Examples of restrictions pertaining to lactating dairy animals Garlon: current restrictions for lactating animals are based on a LACK of residue testing . Residue testing has now been completed and results accepted by EPA for review. It is anticipated that the restrictions for lactating dairy animals will be lifted sometime soon.

Other types of labeling restrictions Some products may have other guidelines relating to grazing or feeding treated forage. Examples from Tordon K:

Haying Most products labeled for haying have a “PHI” (Pre- Harvest Interval). The PHI is the length of time that must elapse after spraying before hay can be cut. PHI may be based on the amount of time needed for the herbicide to act in the target, and/or the need for herbicide residue degradation.

PHI for common ROW herbicides Remember, not all products labeled for ROW allow haying. HERBICIDE PHI Garlon 14 days Tordon Milestone Opensight Arsenal (spot treatment) 7 days Plateau 2,4-D Rodeo 36 hours Transline No PHI restriction

A Conundrum DMA4 IVM The label makes no mention one way or another about haying or grazing (does not permit or prohibit). 2,4-D has tolerances for grazing and haying, which is listed in the RED (EPA’s Reregistration Eligibility Document). The RED restriction that pertains to haying is a 7 day PHI (pre-harvest interval) of 7 days. Many range and Pasture products contain 2,4-D. Dow AgroSciences is in the process of adding Range and Pasture uses to DMA4 IVM. According to MN DOAg, as the label now stands, it would be difficult to regulate someone cutting roadside hay, who observes a PHI of 7 days.

Many ROW herbicide products have residual activity: Residual activity provides prolonged control of difficult-to-control plants (e.g. Canada thistle, leafy spurge, spotted knapweed). This includes: Picloram TORDON, PATHWAY Clopyralid TRANSLINE Aminopyralid Milestone, Opensight Aminocyclopyrachlor Streamline, Perspective, Viewpoint Imazapyr Arsenal, Habitat, Viewpoint

Residual Herbicides Exercise care when spraying around sensitive crops: Avoid drift onto sensitive crops by using large-droplet nozzles and drift control additives Avoid applications where rainwater runoff drains into sensitive crops Do not use clippings from treated vegetation for mulch or compost

Residual Herbicides labeled for Grazing and Haying When livestock consume treated pasture or hay that contains herbicide residue, what happens to the residue? It passes through the animal unchanged: it is not generally metabolized or retained in the body. Residues may be excreted in urine, manure or milk. Residues are broken down by micro-organisms in the soil. In cold temperatures, half life is prolonged because micro-organism activity is retarded.

Residual Herbicides labeled for hay Hay made from grass treated with a residual herbicide should be used on farm, unless labeling allows otherwise.

Herbicide Residues in Manure Follow label guidelines for moving animals from treated pasture to sites where broadleaf crops may be planted in the near future. Handle manure from animals eating hay or pasture treated with residual herbicides in accordance with label guidelines. Refer to the product label for sites where manure may be spread: sites vary by product. 1st bullet point: The same precautions apply to animals that have been consuming hay made from treated sites. 3rd bullet point: an herbicide product must have passed tolerance tests for the crop that will be grown on the land where manure is spread (see next page where manure from animals eating grass treated with Milestone – aminopyralid- can be spread where corn or wheat will be grown, in addition to sites labeled for it’s application, like CRP, pasture and rights of way).

Example of Stewardship labeling for Milestone

SUMMARY Some right of way herbicides allow grazing and haying; some prohibit it. Product uses and restrictions regarding grazing and haying vary: read each product label carefully (rates, PHI, livestock withdrawal, etc). Many ROW herbicides are residual products: follow label instructions for grazing, haying, composting, mulching and manure management. Proper use protects these tools for the future.