Environmental Commitment

Environmental Research — Herbicides and the Environment

The potential impact of vegetation management herbicides has been studied almost as long as they have been used. The environment is always an essential element to account for when managing vegetation. Using management tools such as mowing, herbicides, biological or a combination of methods all can have an effect on surrounding ecosystems. There are numerous studies that examine the different management methods as they relate to environmental impact.

Maintaining the biodiversity of the landscape has been an increasing concern for vegetation managers over the past few decades. It’s the main driver for habitat managers looking to remove invasive species from native settings. Lessons learned in those programs can be applied to all manners of vegetation control. No matter how you look at it, vegetation management is best executed when three goals are met: safety for workers, reliability of infrastructure and maintaining a healthy, biodiverse area.

Maintaining Biodiversity Using Herbicides

The need for biodiversity isn’t new — and neither is the research that’s been conducted to determine the best way to make it happen.

Biodiversity is nothing more than a technical term for a simple concept — allow native plant and wildlife habitats to thrive. Enhancing biodiversity in a region means improving an area’s wildlife and plant habitat by controlling unwanted vegetation. And herbicides can play a key role in achieving this. Combined with other management methods, selective herbicides often promote a native prairie-type ground cover that not only discourages woody plant infestations but also improves wildlife habitat.

This isn’t just an opinion. It’s backed by more than 60 years of scientific research.

Bramble and Byrnes Environmental Research: The Pennsylvania State Game Lands 33

In 1953, a group of inquisitive researchers hiked out to one of Pennsylvania Electric Co.’s transmission lines, set up some instruments and began to measure the effects of vegetation management on wildlife.

Now, more than 60 years later, the research of these dedicated Purdue University scientists continues, with some of the industry’s most useful information being gathered from the Game Lands 33 research site. The researchers’ names — Drs. William Bramble and William Byrnes — have become synonymous with the term “biodiversity.”

This project has produced numerous studies and findings. A full listing can be found on the Bramble & Byrnes site.

Environmental Responsibility

We take this work — and its stewardship responsibility — seriously. To satisfy the needs of our growing world population, we focus on discovery and development of greener and more sustainable solutions, further developing our capability in targeted delivery systems and fully meeting our compliance obligations. Participation in the Responsible Care^® program through the U.S. Environmental Protection Agency is a voluntary initiative to safely handle our products from inception in the lab through disposal.

Product delivery systems such as Continuum^® Prescription Control & Container Management System give added environmental benefits to users. In addition, Corteva Agriscience™ has local territory managers available to help vegetation management programs run smoothly and efficiently.

Application Site Considerations

There are a number of things that should be done prior to spraying to help ensure a successful herbicide application.

Read the label: It provides approved use sites, specific directions and restrictions about the use of the product and treatments. It also lists what personal protective equipment (PPE) to wear and gives first-aid instructions. All labels for products from Corteva Agriscience have been approved by the EPA.

Know the site and conditions: Survey the application site and adjacent areas to identify target species, susceptible crops or nontarget plants in and around the site. Also, most herbicides cannot be applied directly into water (only aquatically registered products can be used in water, and state regulations apply to their use). Corteva Agriscience provides numerous herbicide options that can be used in and around aquatic sites.

Know the weather forecast and monitor conditions: Be sure to account for wind speed and direction; rainfall, predicted timing and amount; relative humidity; and air temperature.

Using Herbicides Responsibly

Much of what you need to use any given herbicide responsibly is on the product label. You’ll find information on PPE, weeds controlled, how to properly mix herbicide solutions, disposal and storage instructions, and much more.

The herbicide label also will outline any special use precautions that need to be taken. For example, Milestone^® herbicide has language on the label that informs users that “manure and urine from animals consuming treated grass or hay may contain enough active ingredient to cause injury to sensitive broadleaf plants.” A user who didn’t read the label may see desirable plant injury when using manure from animals that have fed on grass or hay treated with Milestone herbicide within the previous three days.

More information on using manure and treated compost or hay can be found below under Aminopyralid Stewardship.

Another example is found in the label for Milestone herbicide. Spray drift can be lessened, “by keeping the spray boom as low as possible; by applying 10 gallons or more of spray per acre; by keeping the operating spray pressures at the manufacturer’s specific minimum pressures and by spraying when the wind velocity is low.”

Although the label is the law, accidents do happen, and you need to minimize your chance for exposure. Having a spill plan in place can make a big difference in how it affects the environment. An important part of this plan needs to include contacting the manufacturer in case of an emergency. For Corteva Agriscience, the number is 800-992-5994.

Minimizing Drift and Off-target Injury

The most common ways that herbicides injure off-target plants are spray drift and herbicide volatility. Spray drift is the physical movement of airborne spray particles during the application that never settle on the target vegetation. Volatility is the tendency of a chemical to vaporize into the atmosphere from a treated surface even after it has been deposited on the target.

Spray drift is affected by a number of factors: nozzle type, application volume, wind speed and adjuvants, to name a few. To minimize herbicide drift, it’s recommended that droplets be larger than 400 microns, as smaller droplets can be easily carried off-site. Obviously high wind speeds increase the likelihood of drift; however, when wind speed is less than 2 miles per hour, wind direction is highly variable and can change direction suddenly. That’s why Corteva Agriscience always recommends a wind speed range for optimum spray deposition. And remember, off-target damage potential increases when wind blows toward susceptible crops. Some states have state regulations for proper wind speeds during applications.

Herbicide volatility varies by product and can occur with applications on any surface, but it increases on impervious surfaces like rocks and pavement. The main climatic situation where volatility occurs is during periods of high temperatures and low humidity, and calm conditions can contribute to volatility. While drift can occur with any herbicide, Corteva Agriscience offers many products that are classified as essentially nonvolatile, the lowest classification utilized by the EPA to describe the volatility potential of a herbicide.

Aminopyralid Stewardship

If you utilize a herbicide from Corteva Agriscience containing aminopyralid, there are certain use precautions and restrictions of which you should be aware, so please review the information below.

Corteva Agriscience is committed to responsible stewardship of products throughout the life cycle. If you have further questions concerning aminopyralid use, restrictions or products, please contact us.

Key Aminopyralid Facts

• Aminopyralid is an excellent selective, systemic herbicide with postemergence and preemergence activity on many noxious and invasive broadleaf weeds that reduce grass forage production and threaten native grassland and rangeland ecosystems.
• Aminopyralid does not have adverse effects on livestock consuming treated forage.
• Aminopyralid does not degrade in plants and takes three days to pass through a grazing animal’s digestive system once treated forage is ingested.
• Manure may contain enough aminopyralid to cause injury to broadleaf plants, including vegetables and ornamentals.
• Aminopyralid is broken down by soil microbes.
• Forage growers must read and understand aminopyralid use precautions and restrictions.
• Forage growers should inform the recipient of hay or manure from animals grazing pastures or feeding on grass or hay from areas treated with aminopyralid of the label precautions and restrictions before applying the herbicide.
• Aminopyralid restrictions include a prohibition on use of hay intended for export outside the United States.

Aminopyralid Products From Corteva Agriscience^™

• Milestone^® herbicide
• Capstone^® herbicide
• Opensight^® herbicide
• Chaparral™ herbicide
• GrazonNext^® HL herbicide

Labels & Safety Data Sheets

Aminopyralid Use Precautions and Restrictions

1. Grasses grown for hay must not be exported outside the United States.
2. Manure and urine from animals consuming grass or hay treated with this product may contain enough aminopyralid to cause injury to sensitive broadleaf plants.
3. Do not use hay or straw from areas treated with aminopyralid or manure from animals feeding on hay treated with aminopyralid in compost.

Grazing and Haying Restrictions on Aminopyralid-treated Grass

1. Do not transfer grazing animals from areas treated with the product to areas where sensitive broadleaf crops occur without first allowing three days of grazing on an untreated pasture. Otherwise, urine and manure may contain enough aminopyralid to cause injury to sensitive broadleaf plants.
2. Do not use treated plant residues, including hay or straw from treated areas, or manure from animals that have grazed forage or eaten hay harvested from treated areas within the previous three days, in compost, or mulch or mushroom spawn that will be applied to areas where commercially grown mushrooms or susceptible broadleaf plants may be grown.
3. Do not spread manure from animals that have grazed or consumed forage or eaten hay from treated areas within the previous three days on land used for growing susceptible broadleaf crops.
4. Manure from animals that have grazed forage or eaten hay harvested from treated areas within the previous three days may only be used on pasture grasses, grass grown for seed, and wheat and corn.
5. Do not plant a broadleaf crop (including soybeans, sunflower, tobacco, vegetables, field beans, peanuts and potatoes) in fields treated with manure from animals that have grazed forage or eaten hay harvested from aminopyralid-treated areas until an adequately sensitive field bioassay is conducted to determine that the aminopyralid concentration in the soil is at a level that is not injurious to the crop to be planted.
6. Do not plant a broadleaf crop in fields treated in the previous year with manure from animals that have grazed forage or eaten hay harvested from treated areas until an adequately sensitive field bioassay is conducted to determine that the aminopyralid concentration in the soil is at a level that is not injurious to the crop to be planted.
7. To promote herbicide decomposition, plant residues should be evenly incorporated in the surface soil or burned. Breakdown of aminopyralid in plant residues or manure is more rapid under warm, moist soil conditions and may be enhanced by supplemental irrigation.
8. Do not rotate to any crop from rangeland, permanent pasture or Conservation Reserve Program acres within one year following treatment. Cereals and corn can be planted one year after treatment. Most broadleaf crops are more sensitive and can require at least two years before planting, depending on the crop and environmental conditions. Do not plant a broadleaf crop until an adequately sensitive field bioassay shows that the level of aminopyralid or metsulfuron present in the soil will not adversely affect that broadleaf crop.

Use Precautions and Grazing and Haying Restrictions

Informing Buyers About Hay From Aminopyralid-treated Fields

If you intend to sell or distribute hay grown in the field treated with an aminopyralid product, you must inform the recipient of the hay about the use precautions and restrictions.