From the Field
Soybean harvest season is here for some growers here in Southeastern Wisconsin that took the chance of planting in-between the wet weather episodes this spring. Many calls had been coming in over this past September for concerns over possible Sudden Death Syndrome (SDS) and Brown Stem Rot (BSR) situations. Growers are battling a now wet start to fall, and rising concerns over late harvest and early frost are now a topic of concern on farm if wet conditions persist, along with the worry over the wide range of in-season soybean maturity across fields.
When looking at your bean fields, SDS and BSR can commonly match each other in the foliar symptomology on the plant, but it is important to look further at the stem and root system in order to determine the disease affecting your field. Splitting the stems on soybean plants in question will help you with determining BSR versus SDS.
In a BSR situation, the center of the stem will be brown and extend from the root system up through the plant. It is a solid symptom of the disease, so taking the time to split the plant in order to make proper diagnosis is important.
In SDS, the center of the stem will remain healthy, but the surrounding root tissue will start to brown or even turn grey. When pulling the root of a plant, look for what appears as a light blue spore mass. This grey/blue tinge will dissipate when exposed to air, so it is a symptom you want to look for as soon as you pull the root system from the ground.
When coming into harvest, there are numerous concerns due to a large range of in-season maturity this year. These challenges include soybean fields that can be mature in some areas, and green in others. When asked what the optimal time would be to harvest, the answer is not so easy to due to many factors. Growers are already harvesting sections of fields that are ready to harvest, leaving the non-mature areas to harvest at a later date. Some are choosing to wait until the whole field is mature, risking losses from shatter and low moisture in the already mature areas. Others are choosing the harvest a mixture of mature and non-mature fields, resorting to drying and storing their soybeans or taking the dockage at the scale.
It is important to get out of the combine to inspect for shatter losses this season while harvesting. The general rule of thumb is in a one square foot section to count the remaining seeds on the ground. Four seeds per square foot = approx. One bushel of yield loss. When harvesting a mixture of maturity ranges in a field, remember that combine moisture sensors may not predict accurate moisture levels due to the range across the field, and you should consider factoring about 1.5% higher than what the sensor is predicting.
I wish you all a safe harvest season, and be sure to include your agronomist in on any concerns and scouting opportunities.