Wheat Response to Foliar Applications of Copper and Zinc.

In recent years, questions have arisen as to whether copper and zinc deficiencies are depressing wheat yields in Kansas.  A two year study was initiated in 2007.  Multiple on-farm wheat production fields where chosen randomly and soil test levels were taken for copper and zinc.  Treatments consisted of 1.12 kg/ha of copper or zinc applied prior to wheat jointing in the spring and an untreated check.  No differences in wheat yield were observed when comparing the copper and zinc treatment to the untreated check.  Therefore, wheat fields having copper and zinc soil test levels of 0.2 to 1.3 ppm will likely not have any benefit from supplemental applications of these nutrients during spring green-up.