By Brian Hefty
In December of 2011, Banvel and the generic dicambas were selling for just under $40 per gallon. Today they are near $80 per gallon. The unbelievable worldwide shortage of dicamba has basically eliminated the opportunity for you to run dicamba inexpensively as a post-harvest burndown.
On the other hand, LV6 is almost identical in price to 4 years ago. While I preferred dicamba when it was cheap in 2011, today your best option is probably LV6 for control of Roundup-resistant weeds post-harvest.
I have fielded many questions in the last couple of years similar to this: “Do you think it’s even necessary to add Roundup to the tank, because it’s not killing anything?” Look, Roundup may not control 2 or 3 weed species on your farm, but it is still an invaluable tankmix partner in almost all burndown situations. It’s much less expensive than Gramoxone, not to mention the fact that Roundup is systemic, a lot better on perennials, and much safer to humans than Gramoxone. Gramoxone definitely has its place, but probably not in your post-harvest burndown.
Years ago many farmers threw in atrazine with Roundup post-harvest, but due to environmental and carryover concerns, that’s not common or even recommended today. Instead, you may consider a product like Valor or Sharpen that has both burndown and residual activity, yet can be safely rotated next spring to most any crop.
Let’s come back to the Roundup because the most common glyphosate question I always get is, “When is the right time to buy?” As usual, we expect prices to come down late summer/early fall for three main reasons. One, dealers are trying to empty their tanks for next year. Two, unless Monsanto incentivizes you or your dealer to take Roundup in the fall to fill up for next year, why would you do it? Three, there is usually a seasonal low in glyphosate prices late summer/early fall due to lower demand at that time. I don’t know what will happen exactly with glyphosate prices, but I feel pretty confident in telling you that July is not the time to load up for fall. In our operation, we’ll wait until we cut our wheat and need to spray until we buy our glyphosate, and that’s what I’d recommend for you, too.
One last thing about post-harvest burndown – don’t get sold something you don’t need. I can’t tell you how many crazy concoctions I’ve been seeing over the last few years because companies want to sell what they’ve got rather than what you need. Work with your local agronomist and make sure the agronomist knows which weeds you’re after. If all you’re trying to kill is grass, maybe all you need to spray is a low rate of Roundup. If your area has been suffering from drought, maybe you should add crop oil or methylated seed oil to your herbicide mix to inexpensively improve performance. If you’re spraying earlier than normal, maybe a product like Valor or Sharpen in the tankmix would help so you don’t have to spray twice. You’ve got lots of options. Just take your time and make the best decision to get great weed control at the lowest cost possible. That doesn’t mean skimp on rates or products if you need them, because having great weed control is worth a lot. Good luck!