Answering Your Top Questions about White Mold in Soybeans

White Mold is one of those diseases we plan for, but we never really know if we will have it until it’s here. It has been a significant concern for farmers over the years, and rightfully so, because of how devastating it can be to the crop yield.  This disease is very different from other vascular and foliar diseases, so it comes with a very different set of considerations to know about. 

Let’s dig into the top questions—and answers—about understanding and managing White Mold in soybeans.


When/where is White Mold likely to show up?

White Mold is most likely to occur during seasons with cooler temperatures and high moisture/humidity in a lush soybean canopy during early flowering. Due to delayed planting in some areas, not all fields will have canopy closure before flowering occurs, which will help keep air flowing under the canopy, reducing disease potential during early reproduction. However, soybeans flower for 3-4 weeks, so if you had White Mold problems two years ago in the same field, you should prepare for a resurgence this year.


How is White Mold different from other diseases?

White Mold infects plants earlier than most foliar soybean diseases. White Mold infects through flowers and destroys the vascular tissue of the plant. As a vascular disease (stem rot), White Mold shuts off water and nutrients to the plant, unlike a foliar disease, which infects through the leaf and reduces photosynthesis.


How does White Mold impact plant health and crop yield?

Significant yield loss may occur from White Mold, depending on when it infects the plants and the size of the infected area. Infected plants can be up to 100% yield loss because White Mold typically kills the plant before it starts seed fill, but this may only be in small areas within a field.

What does White Mold look like in the field?

To identify White Mold in your fields, look for fluffy, white growth on the lower stem during mid-to-late reproduction. Plants also begin to wilt and look drought-stressed, with a gray tinge to them from the road. They may also show foliar symptoms similar to Sudden Death Syndrome or Brown Stem Rot, however, the whole plant will eventually turn brown and die. Black sclerotia can also be found inside the stem. Look for little black pellets inside the stem, as the picture below shows.

When should I scout for White Mold?

It is difficult to say when to start scouting for White Mold. Typically in late July or early August, if you see heavy fogs in the morning or continued leaf wetness, those are good indications to start to walk fields or call your Liqui-Grow Sales Applicator. At this point, plants are typically in the R3-R4 growth stage and visual symptoms should start to appear. 

If you see dull, gray isolated round spots in your field, those could be early signs of White Mold setting in. However, at this point, if you do see White Mold in your fields, it is often too late to save the infected plants. All you can do is make a plan to avoid the disease in your next soybean crop.

Is there any way to treat White Mold once it occurs?

A fungicide at R1 is really the only way to stop or reduce White Mold infection. However, an R3 fungicide application may reduce severity and avoid 100% yield loss from infected plants. 

Many fungicides labeled for White Mold recommend an R1 application followed by an R3 pass if expectation for disease is high.  Once again, your Liqui-Grow Sales Applicator has been trained and is knowledgeable on the chemistries available to combat and minimize White Mold.

How can I prevent White Mold in my fields?

Managing White Mold is about preventative measures.  

  • Identify which fields have shown White Mold issues in previous years and let your Liqui-Grow Sales Applicator know as you prepare for the next cropping season.  
  • Choose soybean varieties with good to excellent White Mold scores. You can also select soybean varieties with tolerance to White Mold and varieties with a “narrow” or less bushy growth habit to help favor airflow under the canopy around flowering. Widening row spacing and/or decreasing planting population also helps increase airflow.
  • Be prepared with a labeled fungicide right as the soybeans are beginning to flower (R1). This is one of the ways White Mold is an outlier: R3 is typically the best timing for most other soybean foliar diseases, but it’s too late for White Mold.
  • Worst case scenario, stay in a corn-on-corn rotation. Although, that has its own challenges. A corn/corn rotation won’t eliminate white mold issues since sclerotia can survive a long time in the soil.
  • Use products like Contans on the field in the fall prior to planting soybeans.  

Watch this Liqui-Grow Loop video to learn more about our tips for handling fields with White Mold.


Your Liqui-Grow Sales Applicator and Agronomists are here to help you prevent and treat diseases in your fields. Get in touch with us to help select the right seed varieties and fungicides to protect against harmful diseases like White Mold.

Text us at 564-220-2508 or email questions@liqui-grow.com.

Managing Crops after High Rainfall Amounts


When it rains, it pours—and that’s not always a bad thing after the dry spells we’ve had over the past few years. But now that it’s drying up in places, don’t forget how much rainfall we have experienced throughout this growing season.

When soils are full of water, or as we say, at field capacity or saturated, nutrients are more readily available for plants to take up and use. This leads to higher growth rates, growing larger, healthier plants that are more capable of producing high yields.

But, too much moisture in too little time can cause some problems in your fields if you’re not careful. Now’s the time to pay extra close attention to diseases, pests and nutrients.


Disease and Pest Management

Regular Monitoring and Early Detection

Regularly inspect crops for early signs of disease and pest infestations. Early detection allows for timely intervention, & prevents minor issues from becoming major problems. 

This spring we have seen multiple cases of seedling diseases in both corn and soybeans. We aren’t able to fix these seedling diseases, but we can make notes for next spring and choose our hybrids differently going forward. Knowing seedling scores can make or break a stand, and our Liqui-Grow Sales Applicators are trained and knowledgeable in hybrid selection and placement.

Many of the fungi that produce the diseases we see in corn and soybeans overwinter in the crop residue and will infect the crop in spring depending if conditions are right. Tillage and rotation often help to combat these fungi. In reduced or no-till systems, we see higher levels of disease pressure. The spring we have experienced so far is potentially setting us up for a disease-stricken year. Some of those factors are:

  • Hard pounding rains splash fungi inoculum onto the leaves and plant and we will continue to see disease grow as the season continues.
  • Winds, hail and rain have created openings or lacerations on leaves, providing points of entry for fungi to infect crops.
  • Water standing for any period of time can deplete oxygen in the soil and stress the plants.
  • Compounding effects of adverse conditions early on this growing season has lowered the “immune system” of the crop in the field. 

This may feel like doom and gloom information, but a lot can still be done to help grow a good crop, and high yields. Dr. Jake fills us in on what to watch for in fields this season in one of our latest Liqui-Grow Loop videos.

Scouting is KEY to Applying Fungicides

The biggest thing this year after all the heavy spring rainfall would be, paying attention and scouting for fungicide applications. R1, for corn, is usually the most effective timing for fungicide, but if disease sets in early, going early might be beneficial to the crop. General recommendations for soybean fungicide is at R3. Keep in mind, R1 and R2 are such short windows for soybeans, you need to have that pass planned and organized in order to be at the field during R3. Heavy spring rainfalls should not change fungicide timing by much in soybeans. But scout for White Mold, which is caused by spores infecting the plant through its flowers, making the R1 time frame critical for disease. 

Fungicide applications can take care of diseases before they even appear, but scouting for those diseases is key! Get in touch with your Liqui-Grow sales applicator to learn more today!

Nitrogen Management

Side Dress, Y-Drop

As the soil profile exceeds field capacity we often are exposed to nitrogen loss, either through leaching or denitrification. 

  • Leaching is when a nutrient is lost deeper into the soil and out of the root zone. Nitrate is carried by the water and because it has a negative charge, the soil won’t hold onto it, and it will leach down into the soil profile, making it unavailable for the plants to use.   
  • Denitrification is when nitrogen is lost to the atmosphere. To hear more about this in-depth, reach out to our Liqui-Grow sales applicators on how to protect your nitrogen source. 

Before you assume you lost a certain amount of nitrogen, you need to know: how much you put down, what was your application timing, did you use a stabilizer, what was the amount of rainfall your farm experienced and what form of nitrogen did you apply. By answering those questions we can help make a recommendation on how much nitrogen you still need. To learn more about nitrogen loss, watch our new L.E.A.D. Academy video.

Utilizing Foliar Feeding

Foliar feeding involves applying nutrients and biologicals directly to the leaves, ensuring that plants receive essential nutrients during critical growth stages, especially when soil conditions are not ideal. Your Liqui-Grow sales applicator can help you decide when a foliar application may be necessary.

Staying in touch with your Liqui-Grow sales applicator is the key to making sure your crops stay happy and healthy with increased rainfall this season.

Questions? Give us a shout! 

Text us at 564-220-2508 or email questions@liqui-grow.com.