b'Its a Jungle Out ThereEncourage aggressive pre-plant management in 2020.Barb Baylor Anderson anderagcom@sbcglobal.netTHE CHALLENGING2019 growing season may have set corn and soybean farmers up for a 2020 weed challenge. Seed advisors are urged to work with customers to establish aggressive pre-plant weed control programs that will help maxi-mize corn and soybean yield potential in the new year.With such a large percentage of no-till corn and soybeans today, you always have to take care of potential weeds right from the start, says Larry Steckel, University of Tennessee Extension weed specialist. And then we had 2019. Especially where we had prevented plantings, fields are weedy messes and winter annuals have become well established in the jungle. Tony Lenz, Stine Seed technical corn agronomist, has similar observations, adding, Prevented planting acres and very wet fields may have a higher weed seed bank supply, too.Cleaning Up After 2019 Recommend planting seeds with trait technologies on the acres With that in mind, starting clean should be standard procedure.that allow farmers to take advantage of the herbicides that match Seed advisors might be best served to provide guidance forthose technologies.the most effective approach to managing broadleaf weeds and grasses for individual customer operations, given additional costalso break up compaction in the soil and help limit diseases that and headaches in 2019. may have overwintered in the previous crops residue, accord-Some farmers had triple the herbicide cost and had to spraying to Lenz. Use of a residual herbicide can then, when activated up to four times to control grasses in 2019, Steckel notes. Otherwith moisture, give up to month-long control on certain weeds. farmers lost corn and soybean yield to weed competition andNo-till or minimum till followed by a burndown product to harvest efficiency was not great because grasses were chokingremove already established weeds that germinate early like up soybean combines. kochia or marestail is a good option, Lenz says.For fields not treated for weeds in the fall, Steckel recom- Pre-plant field management is critical to control these weed mends spraying before any weeds green up at least once in thespecies and even resistant weeds. spring and possibly more times. Even for fields that did get a fallOther tough-to-control weeds like waterhemp, ragweed and treatment, a second shot in the spring may be needed, givenespecially resistant Palmer amaranth can be yield robbers if not the weed challenges of 2019. He adds that farmers who plantedcontrolled early in the season, Lenz says. Get corn and soy-cover crops last year may be in the best position for early weedbeans off to a good start to shade the crop rows and help with control. Steckel says a good stand of cover crops diminishesweed control and yields.winter annual weed growth. Lowell Sandell, FMD specialist with Valent and previous Other tips to put 2019 in the rearview mirror include tillingUniversity of Nebraska Extension weed science educator, notes right before planting to not only help with weed suppression, butmultiple studies have shown if weeds are allowed to grow to 10/ SEEDWORLD.COMJANUARY 2020'