Abstract
Field experiments were conducted in Prince Edward Island, Canada to determine the effect of Cu applied in the form of copper sulfate as a foliar spray and to the soil; and the effect of chelated Cu as a foliar spray on Cu concentration and yields of wheat (Triticum aestivum L.), oats (Avena sativa L.), alfalfa (Medicago sativa L.), and timothy (Phleum pratense L.). Copper treatments had no significant effect on the yield of cereals or forages (data not reported). The Cu concentration in the check treatments ranged from 3.4 to 6.6 μg g‐1 and 4.4 to 12.1 μg g‐1in the cereals (boot stage tissue and grain) and forage plant tissues, respectively. The cereal grain Cu concentration was not affected but the boot stage tissue and first cut forage tissue Cu concentration increased with Cu applications with highest values occurring in the foliar spray treatments. The first cut of forages from the soil and foliar applied Cu treatments generally had more Cu than the second cut. The Cu values as high as 54 to 55 μg g‐1 in timothy and wheat were not related to Cu toxicity.