By: Scott Fleming, CCA, TSP
Tissue sampling is generally something thought of in early growth stages prior to herbicide application. While this common use of tissue sampling will always have a place in agronomic decision-making, another form can also play a huge role. Enter early reproductive stage tissue testing.
A plant has been through a lot to get here. It was placed in cold, muddy soil and waited days or weeks to spring to life. With the whacky weather of spring 2023 it may have even seen a little frost or snow. Once things finally dried up enough to plant, plants started to look more like pineapples than corn plants. Even in a year like this, reproductive stage tissue samples serve a valuable purpose.
How can it possibly help this late?
Testing at early reproductive stages is an excellent evaluation of where things stand at the most vital stage of development. Corn, soybeans, or any other annual plant has completed the majority of its vegetative growth and is preparing itself for setting seed. A plant tissue sample at this time is a great evaluation of what is in the plant at this critical stage. This will help determine how effective the fertilizer program was at supplying the plant with everything it needs for a successful harvest. If deficiencies are seen, it may be time to take action to remedy the issue.
Deficiencies shmifiencies
Deficiencies don’t always mean you are short on that nutrient! The soil and plant interface is definitely not straightforward and simple. Many things affect the amount of a particular nutrient in a plant. A couple prominent items this year are root systems and drought. Many nutrients are brought into a plant with the water it drinks. Without water, nutrients may not have been taken up and into the plant even though they are present in the soil.
Another common cause of low plant tissue levels and adequate soil nutrients is poor root systems. Poor root systems can come from many places, but pushing the planting window and working and planting into soil that is a little too wet can cause stressed and weak root systems. Root-feeding insects or nematodes may also be at work. But what is the solution to this problem!?! A shovel and a soil test. Dig some roots and wash them off to check the plants' foundation. A soil sample should always accompany a tissue sample. Comparing sufficiency levels in BOTH plants AND soil will help you see the entire picture.
It may not be too late to take action if a specific nutrient is found to be in deficit. Fungicide applications could include a foliar fertilizer to help remedy the deficiency. While this may not be a permanent solution, it could help the 2023 crop finish the season strong. It also may tip the scale on the decision of applying a foliar fungicide.
