Dr. Henry Wu, technical sales support representative, Chemtura AgroSolutions
With harvest wrapping up, now is a great time to address vineyard fertility, maintenance and clean-up.
That means soil testing, applying potash if needed and adding some fertilizer through the drip to put vines to rest with nutrients. Fall is also a good time to apply compost or manure in organic systems.
Of course, the most important thing to remember when it comes to fertility management is to put on the right type of fertilizers at the right time. And that’s why soil testing and good fertility programs designed around these results are so important.
Watch for weed escapes
Now is also a good time to start thinking about winter weed control programs.
Start by looking at the weeds that escaped this summer and plan your control program to address these challenges, especially if you are dealing with glyphosate-resistant weeds.
As you well know, glyphosate-resistant horseweed (marestail), fleabane and ryegrass have taken root in many California vineyards, which endangers the long-term efficacy of glyphosate as a weed control tool. Controlling these weeds through herbicide rotation is the only way to prevent them from producing seeds with the resistant trait that will grow next season.
Glyphosate-resistant weeds are easiest to control when they are small (less than 3 to 4 inches) and actively growing — typically from January through March — so plan accordingly.
A tank-mix combination of a non-glyphosate burndown herbicide and a residual product can control the first flush of emerging weeds as well as succeeding flushes. Firestorm® from Chemtura AgroSolutions knocks down glyphosate-resistant weeds and fits well into this management strategy.
To help identify and treat weed species that have invaded your vineyard, visit the University of California Extension’s Weed Research and Information Center.
This resource includes a database of weed susceptibility to herbicides, links to pages with information about specific weeds and control options, as well as a weed identification tool that allows users to enter the physical characteristics of the weed to confirm identification so you can maximize control and enter the 2013 growing season ready for success.