Late season scouting can help you create an order to harvest your field to minimize harvest loss. When you scout it is important to know specific yield limiting factors to look for. Walk into your fields and be able to answer these questions to decide if that field is one that needs to become a harvest priority. After answering these questions be prepared to take action if the field is at risk of falling or dropping yields through lost ears or pods.
1. What maturity is the product? When you know the maturity you can make a plan for when it will reach physiological maturity. In corn, a general guideline is it reaches black layer 55 to 60 days after silking. At black layer it is about 32% moisture, says Jeff Coulter, Extension corn agronomist atthe University of Minnesota.
2. When was the field planted? Planting date will tell you if it had stress early season and if it will be mature sooner than other fields. Stress early season can cause lodging and other problems even into late season.
3.When did it pollinate? Was there insect, heat or drought stress during pollination? The plant puts all of its energy into producing ears during pollination. If it needs more nutrients or is under stress it will steal from the stalk to provide for the ear. This hollows the pith and makes a very weak stalk.
4. What is the rotation? Corn-on-corn fields face different pressures than a soybean-corn rotation. There are fungi and diseases that never dissipate because the field never gets a break. It is important to be aware of any additional risks your crops may experience.
5. How does rotation affect disease history? Watch for overwintering diseases. sudden death syndrome and northern corn leaf blight are two diseases that can be detrimental on corn and soybeans. Both overwinter in soil and corn residue. Keep track of where you had these problems to see if you need to take action.
6. What diseases or fungi are present in the soil? Soil borne issues like anthracnose, southern rust, common rust, smut, gray leaf spot, brown spot and other stalk rots are present in soils. Keep an accurate history of your field and any areas with problems to track where you may need to spray fungicide or harvest early.
7. Was the field under stress this year? What kind of stress? Did you have drought, too much water or nutrient leeching? Drought can bring out mold such as aflatoxin which can mean problems at the grain elevator and harvest. Too much water may encourage stalk rots and cause poor standability. And lacking nutrients means the plant will rob from the stalk to feed the ear which makes it hollow and easy to knock over.
8. What disease or rots are out now? Use pocket guides to determine what kind of diseases or rots you are seeing in the field now. This can tell you the severity of what you are dealing with and if it will have a big affect on standability the rest of the season. Leaf rots can also rob from the stalk so it will be important to identify those while planning harvest.
9.Are there ears or pods lying on the ground already? A weak ear shank can cause big losses as your money literally falls to the ground with each ear you lose. The same goes for soybeans, as they hit the ground less money goes into your pocket. Be vigilant as you check for ears and pods on the ground so you don’t harvest too late an lose it all.
10. Does the stalk pass the push test? As you walk the field, push stalks to test their strength. “Anytime I get more than 10% to 15% [hollow stalks] I tag that field as an early harvest option,” says Troy Deutmeyer, Pioneer field agronomist in Northeast Iowa. That is a potential 10% to 15% yield loss and could indicate the rest of the stalks are weaker too and could fall with a strong wind.
Be thorough during your end of season scouting. You don’t want to lose yield this close to the finish line because in tight years every bushel counts.