Is it ok to inject chicken manure into fields this time of year?
Feb 11, 2014
Question: What harmful effects might injecting chicken litter into fields this winter have on soil fertility and/or soil structure?
Answer: From a chicken litter standpoint if you’re injecting it now you have to think about what the carbon-nitrogen ratio is in the chicken litter. Straight chicken manure with no bedding will have about a 10-to-1 carbon-nitrogen ratio. That’s not a problem. But if the chicken litter has any bedding with it like wood chips, the carbon ratio could go up and this could create a nitrogen deficit situation for the crop you’re planning to grow. So, in corn for instance, instead of getting a nitrogen return from your manure it could take six months to a year to get the nitrogen out of the manure and that could create a nitrogen deficiency in your corn. From a fertility standpoint what’s the carbon-nitrogen ratio? If it’s 20-to-1 or lower, you probably will have no negative effects from that perspective. From a soil structure standpoint you have to consider the salt load. Depending on the soil type, it can hold from 300 to 600 units of salt without too much damage. But if you’re injecting upwards of 600-plus pounds of salt per acre you could destroy the soil structure. That’s broadcasting it. Now, if you took that 600 pound of salt and banded it, you would destroy the structure in the band. You can check your salt index when you run a manure analysis. If you keep your salt applications typically below 300 pounds per acre you don’t usually have much of a problem. But if you get into levels above that you could destroy the soil structure. Also, in regard to soil structure, the timing of application matters if you have to deal with the results of wheel track compaction. In terms of a carbon penalty, the more time you have ahead of planting for the litter to break down the less of a carbon penalty you would have versus if you make an application a few weeks ahead of planting.