By Dr. Henry Wu, Technical Sales Support Representative, Chemtura AgroSolutions
Since weeds can vary from year-to-year — and even from area-to-area — it’s a good idea to take a look around your vineyard a couple of times a year to assess which species are present.
Use the results of these weed surveys to determine the best control practices and track the spectrum of weeds with which you must contend. This helps you to make informed weed management decisions about herbicide choice or cultivation equipment and practices.
The survey records also enable you to track weed population information from year-to-year to better understand ongoing weed control problems, such as resistance.
According to experts at the University of California, here are some hints as to how to survey your fields for spring and winter weeds:
• Survey your vineyard in late fall/winter to identify winter annuals and perennials and again in late spring or early summer after summer annuals have germinated.
• If you use cultivation for weed control, monitor at least two weeks before you plan to cultivate.
• Pay particular attention to perennials. Check for regrowth of perennials a few weeks after cultivation.
• Pay attention to “wet spots,” as these may be problem areas in terms of weed growth.
• Survey areas around the vineyards, as these areas could be a potential source for wind disseminated weed seeds such as marestail, fleabane and more.
• Sketch a diagram of the vineyard and mark areas where you found perennials.
• Keep records of your survey results. By knowing what species are present, you will be able to make appropriate control decisions.
Information collected over a period of years tells you how weed populations may be changing and how effective your management operations have been. This way you can see how well your weed management actions are working.
Firestorm® from Chemtura AgroSolutions can be a great partner in your weed control program. With 3 pounds of active ingredient per gallon, Firestorm is a contact herbicide for control or suppression of a broad spectrum of emerged weeds and grasses. When applied in a tank mixture with a residual preemergence herbicide, Firestorm will either control glyphosate-resistant weeds or prevent them from surviving and producing seeds that will emerge the following season.