Is it possible to spread FRESH chicken manure onto soil in a raised bed from August to about February and let the rain and snow get at it to dilute the nutrients, then dig it in for vegetables to grow in the coming season around may time? Each day I clean the henhouse and put the manure on the beds and was wondering if this was worth doing or if the nitrogen will still be too high?
Chicken manure and bedding (collectively called poultry litter) can be turned in to the top several inches of garden soil and left to compost in place, in which case soil organisms aid in the composting process and nitrogen is released directly into the surrounding soil. The Washington State University Extension Service advises that pathogens in chicken manure, particularly E. coli, can present an ongoing human health hazard in crops harvested where fresh manure has been spread. They recommend waiting at least 120 days from the time you turn chicken manure into the soil until the time of harvest of any crops intended to be eaten by humans uncooked (such as strawberries).
The following article discusses composting with chicken manure: http://seattletilth.org/learn/resources-1/city-chickens/compostingchickenmanure