Update on nitrate levels in forages this fall in Kansas
Volunteer corn is another problem. More than half the samples identified as volunteer corn had high nitrate levels. This is a special problem as the nitrate level will not go down as these plants die, and this material will be preferred grazing for many cows and calves compared to the stalks in the field from the full-season crops.
The good news from the sampling to date is a high percentage of the sorghum stalks have relatively low nitrate levels. Some are high, however, so testing individual fields will be important. If nitrate levels are acceptable, these acres could be available for grazing.
Also, about 75 percent of the sudan and forage sorghum forage samples tested by our lab have low nitrate levels. These are important supplemental forages for many Kansas cattlemen.
In summary, nitrate levels in many forages in Kansas are high this fall, and likely will stay that way until spring. This will require careful sampling of forage supplies to avoid nitrate poisoning of livestock this winter.