However, it is best to wait for regrowth before haying or ensiling also. Prussic acid levels are reduced by HCN being lost as a gas during hay curing or silage wilting. Some prussic acid is also lost during handling of silage for feeding. Silage should not be fed until it has ensiled for 3 weeks. DO NOT enter unventilated silos once ensiling has started.
Little information is available on the safety of round bale silage.
Testing forage for prussic acid may be beneficial. Hay and silage should be tested after proper curing or ensiling. The Toxicology Laboratory at the Virginia-Maryland Regional College of Veterinary Medicine can test for prussic acid. Samples must be kept frozen or well refrigerated in plastic bags from the field to the laboratory. Other commercial laboratories may offer this service.