Timely In-Season News from Your Federated Agronomists
White Mold on Soybeans: Preventable, not Treatable

soybeans with white mold
"White mold is terrible," said Bob Marquette, Federated agronomist at the Albertville location, adding, "It's a big problem, and though it depends on the season, Federated saw a lot of it last year."
Unlike many yield-robbing pests and diseases, white mold can't be treated. It must be stopped before it starts. Sclerotinia stem rot - white mold - can affect high-yield-potential soybeans and it thrives under moist conditions and below average temperatures. Several other factors create the ideal environment for white mold to grow:  
  • a dense canopy of soybeans;
  • susceptible soybean varieties (some are more vulnerable than others);
  • a field history of white mold.
While no variety of soybeans is completely tolerant of white mold, the fluffy cottony growth on the outside of pods can be prevented with crop management that includes the following strategies.
  • Consistently rotate between corn and soybeans (but if white mold is present, it is necessary to keep a field out of beans for three to four years, until the sclerotia dies).
  • Avoid dense canopies with wider row spacing ("Lower populations will help," said Marquette).
  • Control weeds; lambsquarter, velvetleaf, ragweed, and Canada thistle, for example, are hosts for white mold.
  • Apply preventive treatments (such as Aproach - see article below); fungicides can be added to many planned herbicide treatments. 
Marquette described sclerotia as small black structures that resemble mouse droppings. "If you slice the stem [of a soybean plant] open, these will be found inside."
It is important to apply fungicides at the right time. Talk to your Federated Agronomist for more info on white mold before it robs yield in your soybean crop.
Fungicides Improve Plant Health to Better Fight Disease

Crop diseases such as white mold (see article above) are minimized when plant health is strong. Federated recommends DuPont™ Aproach® fungicide to help ward off white mold in soybeans. Aproach is a broad-spectrum fungicide that provides more complete coverage with its rapid absorption into and within the soybean plant.
Aproach is both preventive and curative against many fungal diseases (see this link on how fungicides move through plants), but white mold, unlike some diseases, can't be treated after it appears. Soybeans need preventive help from fungicides such as Aproach.

While it can be challenging to hit the ideal timing for fungicide applications, for white mold suppression in soybeans, the timing should be between R1 and R2, early flowering to full flower, according to Bruce Carlson of DuPont.
Aproach applied R1-R2 (@9 oz./ac.) will help suppress white mold and provide overall disease control; it can be applied at R3-R4 (@6 oz/.ac.) for overall disease control and improved plant health. For fields with a history of heavy white mold, or if the weather becomes conducive to white mold (cool and wet), a second application 10-14 days later will improve the control of white mold.
For additional information on fungicide application and timing, talk to your Federated Agronomist.
In-Season Crop Management Reminders

Chase the Weeds
weeds in corn
"Get the corn clean and then start chasing the weeds in beans," Kevin Carlson, Federated's senior agronomist said. The crops are growing nicely - but so are the weeds.
"Giant ragweed is more than doubling and tripling in size in four to five days," said Carlson. It's important to be paying close attention to what's happening. "Monitor fields and get herbicides on as soon as possible," he said, noting that the soybean pre-emerge herbicides are "really paying off because it's giving us a good chance to get things set up for a second pass."
The pre-emerge herbicides worked "quite well," he noted, and most of the area got the moisture that was needed.
Some areas were adversely affected by a hailstorm, and growers in those areas are facing a different sort of challenge, but most growers in Federated's service areas are challenged by the fact that many things are happening at the same time because crops were planted closer together this year. That doesn't change the need for "growers to monitor their fields," said Carlson.
Scout the Soybeans
weedy soybean field
Matt Kurtz, manager at Federated's Rush City location, stressed the need to "check early and check often." Soybeans need to be systematically checked, especially those with a history of weeds or disease. "Many weed and insect issues can be identified early and dealt with accordingly before any major yield damage has occurred," he said.
Kurtz also noted that the tight margins on the farm heighten the need for preserving - and maximizing - yield, "especially when it comes to weed control."
He noted that some of the more challenging weeds, such as giant ragweed and waterhemp, can get out of hand very quickly if fields are not regularly scouted. "Those two are specifically difficult to control post-emerge in soybeans."
Similarly, the aphid population can explode to threshold levels in a matter of a couple days and cause irreparable damage to the soybean crop. Scouting early and often will help growers see when treatment is needed, and get it done expeditiously.
Carlson reminded growers to "stay in touch with Federated [especially if you want custom application], and always ask the important questions of your Federated Agronomists.
As an added note, RR 2 Xtend® soybeans have been planted in several areas and "we are just now starting to 'play' with the chemistry [such as Engenia®] in those fields," said Carlson. He noted the especially important need to read and follow label directions regarding nozzles, drift, etc., to help steward that product and trait.
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