Thinking about applying poultry litter in the fall prior to a small grain? Dr. Steph Kulesza, Extension Specialist in Nutrient Management and Animal Waste, shares some important information on keeping your fields in good condition in this video:

Use your waste analysis and soil test reports to make application decisions to avoid zinc or copper toxicity. Poultry litter, dairy manure, and swine manure contain varying levels of zinc and copper, and while these micronutrients are necessary for crop production, they can accumulate over time with repeated manure application, becoming toxic to plants in extreme cases. If the Zinc-Index (Zn-I)
or Copper-Index (Cu-I) exceeds 3000 on your soil test report, application of manure should cease, as all manures contain some quantity of these micronutrients.

If you see a toxicity issue, soil turnover and liming are two of the only options for growers. However, soil turnover should only be used once, with no further application of zinc or copper-containing fertilizers (including manures) to avoid further issues. Growers should also be careful not to expose acidic subsoils through this process. When liming to a higher pH, manganese deficiency can become an issue so keep a lookout for manganese deficiency symptoms and apply a foliar fertilizer if symptoms arise. At the end of the day, the best strategy to manage zinc and copper toxicity is to avoid soil accumulation using soil testing and waste analyses.

Learn more about taking a representative soil sample and submitting a waste analysis sample.