Elevore^®

Marestail is the first annual broadleaf weed documented to develop glyphosate resistance. The spread of herbicide resistance can cause significant challenges at planting and throughout the growing season if left uncontrolled. A single female marestail plant can product up to 200,000 seeds that are transported by wind, providing for effective spread of herbicide-resistant populations. Trials across the Midwest and Midsouth conducted by farmers and retailers demonstrated consistent and thorough control of glyphosate-resistant marestail up to 8 inches tall, with no regrowth, allowing farmers to plant into clean fields.

Common lambsquarters is one of the most problematic weeds affecting soybeans, particularly in the Midwest. Mature common lambsquarters plants can produce more than 70,000 seeds, enabling the weed to return to bloom for multiple repeated seasons. Seed dormancy contributes to the weed’s success, as some seeds can remain viable for years in the soil under certain conditions. Resistance to ALS inhibitors and glyphosate has become more common in recent years, making control using only postemergence herbicides problematic. A burndown application with Elevore® herbicide is an effective control option, while also allowing greater flexibility for postemergence application, if necessary.

Henbit and deadnettle are very similar and easily misidentified for each other. Both are members of the mint family and classified as winter annuals because both species germinate in the fall, overwinter as green plants, begin growing again in early spring before completing the life cycle by going to seed in the spring or early summer. Henbit and purple deadnettle are known to be hosts for many insect and disease pests, and mature seeds can survive in the soil seedbank for several years. Planting into dense patches of these species can be challenging and could result in poor seed placement. The fact that the majority of henbit and deadnettle plants have bloomed and seeded by early to mid-April in most Midwest states makes a burndown application with Elevore more effective than a postemergence herbicide application.

Cutleaf evening primrose is a winter annual that has become especially prevalent in no-till corn and soybean fields. It can grow up to 28 inches tall or reset and creep along the ground. The seed of cutleaf evening primrose can remain viable in the soil for several decades, making it an ongoing control challenge. The yellow sometime pinkish flowers that begin to appear in late spring open in the evening and wither closed the next morning. When applied alone, glyphosate provides only moderate control, which is why the prelevance of cutleaf evening primrose in no-till crop production fields has increased. Effective control of this weed can be achieved by tank-mixing Elevore with glyphosate or 2,4-D as a burndown application. Application timing should be targeted when plants are in the rosette stage of growth, as plants become more difficult to control as they mature and begin producing flowers.