copper in Michigan soils

Asked May 31, 2019, 4:03 PM EDT

I strongly suspect a copper deficiency in my herd of goats and have read that some soils are quite deficient in copper. How do I find out if the soil(s) on my farm are deficient in this? My farm is in Newaygo County, Garfield Twp. Salle

Newaygo County Michigan

1 Response

The best way to determine if your soils are low in copper is actually to test the level of copper in the plants that grow on them. So, you can test your pasture or hay crop from your land for copper concentration by sending a forage sample to a forage testing lab. You would want to ask to the testing package that uses a "wet chemistry" methodology for copper which is often part of a test package for mineral content and will include tests for other important minerals.

In general, copper levels in forages from Michigan soils are moderate and not high or low but exceptions exist especially when poultry or swine manure is applied to land at high levels. In these instances, the copper levels may be quite high.

The suggested requirement for a typical goat diet is 20 ppm of copper in the total diet. Generally you would need to provide extra copper to meet this requirement than what is found in forages but again, the actual forage test will tell you how close you are to the requirement level. It is fairly simple to supplement copper in a goat herd by using trace mineralized salt with added copper.

The challenge is to provide copper to goats if they are cohabitating with sheep as sheep generally do not need supplemental copper and as their requirement is much lower and most often met simply by feed copper content. It is possible in such cases to provide goats with a special, slow-releasing copper supplement in the form of a bolus so as to target just the goats to prevent possible copper poisoning of the sheep.