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On August 13, 2018

To Manage Flood Damaged Crops

The pattern of heavy rains with flooding in certain areas has been repeated for several weeks. This has created management challenges for cropland such as these. Extension specialists Greg Roth, Jud Heinrichs, and others explain affected fields will contain a lot of debris and plants will have a lot of soil on them. Conditions will be dusty and dirty during harvest. Farmers can expect extra costs from wear on shear bars, knives and bearings. The silage made from flood damaged fields can range from acceptable to black or rotten.

Decreased milk production and performance is likely when flood damaged crops are fed.

If fields sustain flooding and significant damage, your crop insurance adjuster to document the loss before taking action to remedy the situation. Consider contacting the local FSA office to report losses as well.

Below are some recommendations and observations that may help in making harvesting and marketing decisions. Corn destined for silage will be more at risk for fungal and bacterial contamination. Take steps to promote good fermentation, such as heavy inoculation and extra packing in the silos. A good fermentation will kill many (but not necessarily all) pathogens in the silage.

Target the least affected fields for silage and harvest above the silt line to avoid soil contamination. Avoid chopping corn for silage that has considerable dirt or silt on it. Segregate any corn chopped for silage so that it can be evaluated before feeding. Forage should be tested before feeding, paying particular attention to dry matter percent, starch, ash, mycotoxins and fermentation profile. Silage and high moisture corn from these fields should be evaluated at feed-out and animal health should be closely monitored. Soil contamination alone may not be a serious animal health factor, but contamination from manure, sewage treatment plants and other chemicals is unknown and could vary from one situation to another. In all cases try to minimize the soil contamination and during feed-out, attempt to dilute these forages with normal quality forages as much as possible. 

For hay and pasture crops soil and organic matter on forage crops can also lead to fermentation issues, increased ash, decreased digestibility, and animal health problems, especially for horses. Avoid pasturing or harvesting silt laden forage crops if at all possible. If pastures are grazed, don’t allow the animals to graze the plants too close to the ground because the majority of the contamination will be in that area of the plant. It might be best to mow the previously flooded pastures and wait for them to regrow before grazing. Mowed forage that has been lying in the field for more than one week should simply be chopped and blown back onto the field, particularly if it is showing signs of molding (forage is slimy). Roots in soil flooded for 2 to 3 weeks may die from suffocation (no oxygen available for the roots to respire). Root diseases such as Rhizoctonia or Phytophthora can increase in wet soils and lead to thinned stands next year. Avoid pasturing or harvesting silt laden forage crops if at all possible.

Harvesting corn for grain is likely a better option than for silage where flooding has occurred. Combine air filters likely will need to be changed more frequently. Operators should take steps to avoid breathing the dust. Harvest when the fodder is dry to help limit the dirt in the grain. Monitor the dirt in the corn coming into the bin and avoid the worst sections of fields.

Harvesting high-moisture corn at the drier range of acceptable levels could improve the ability to clean dirt from the corn. The expected quality of grain is uncertain and should be monitored. The potential for crop contamination by flood waters could affect the marketability of grain and silage. Check with grain brokers for more information on marketability as it becomes available. Monitor for sprouting. Some river bottom fields are prone to bird damage and often have some sprouting risk. The flood may exacerbate the problem. Try to adjust the combine to remove most of the sprouted grain.

It will be important to monitor for molds. Corn from flood-damaged fields should be evaluated for grain quality and kept separate if there are indications of molds. Mold and mycotoxin levels can be determined by most feed testing laboratories and used as guidance in marketing. The risk of molds and sprouting is likely a function of the exposure to the water and stage of growth. Corn that was under water will have an increased risk for molds and bacterial rotting. This may be more pronounced in corn that was already drying down (<40% grain moisture) and then took on moisture during the flood. Monitor for bacterial stalk rots. Fields that remained flooded for more than 12 hours are most at risk for stalk rots.

The crop may mature more rapidly under these conditions, since corn that has been stressed when near maturity often seems to dry down fast. If the grain is deemed unfit for animal use, then it will be necessary to pursue crop insurance claims. If producers expect a claim, they should consult with an adjuster prior to harvest.

Soybean crops likely will experience increased harvest losses and increased machinery problems during harvest. Many soybeans may be impossible to harvest due to lodging and debris. Monitor grain quality prior to harvest.

In summary, flood-damaged crops are at risk for quality and harvest losses, but by monitoring and managing carefully, we may be able to salvage some of them, reduce losses and obtain resources for recovering from the situation.

To Scout For White Mold In Your Soybeans

With moist and humid conditions this year, high reports of white mold is no surprise. Extension Plant Pathologist Alyssa Collins reports the fungus that causes this disease thrives on the soil surface and lower stems when the environment is humid with a closed canopy that prevents air flow. The stem and lower leaves become infected, and then the disease moves up the plant resulting in yellowing and defoliation. As it progresses, white tufts of fungus are visible on the tissues of the lower canopy, and ultimately hard, black overwintering structures (sclerotia) form that can survive in residue and in the soil for many years.

Where did the fungus come from? Well, most likely it was moved into the field as one of these little sclerotia with tillage operations or on other equipment, but this could’ve happened years ago since they live so long. The tough sclerotia may have been lying in wait for a long time before the weather was right to start growing and infecting again.

Now what? Survey your fields just before the majority of the leaves start yellowing naturally. If 20% or more of a field is affected by white mold, the variety you are growing is probably not the right one for your situation. Work with your seed reps to select a white mold resistant variety for the future in that field. Not just the next time you grow soybeans–every time you grow soybeans in that location. This fungus can survive in residue and soil for 7 to 10 years. Tillage may help the first year by burying the sclerotia, but the next time you till, you could bring them up again. There are no 100% resistant varieties for white mold, but there are varieties that are better than others, and since once you have the pathogen it doesn’t go away, this is one of the strategies you should employ for management.

When you harvest, try to harvest these fields last. The sclerotia can and probably will end up in your combine, so you want to avoid moving them to clean fields. If you have someone come in to custom harvest, warn them that they will probably want to clean the combine as much as possible before moving on to someone else’s farm. Apply this same thinking to all your operations in the field that involve soil movement. Anytime you sink equipment into the soil (tillage, planting) there is potential to pick up some fungus and move it to a clean field. Do these operations in your white mold field last, or blow out and power wash your equipment between fields.

When you plant beans in this field in the future, you’ll want to consider applying a fungicide at or before R3. There are some effective products available, but you need to get them on before the canopy closes to be sure you can penetrate down to the lower stems. 

Alfalfa is an alternate host for white mold. Corn and cereals are among the plants that are not affected by the fungus that causes white mold. So, if you have grasses in your rotation, they will not increase the fungus in your fields.

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