I am wanting to plant a summer annual or a mix to use as forage for a small...

Asked May 3, 2019, 1:38 PM EDT

I am wanting to plant a summer annual or a mix to use as forage for a small herd of rotational grazed cattle. At present I am leaning towards a mix of 12.5 lbs of pearl millet BMR, 6.25 lbs of sunn hemp and 2 lbs of daikon radish per acre. My concern is nitrogen, specifically nitrate poisoning. I want to apply 2 tons of chicken litter as fertilizer prior to planting to meet my P and K needs. The analysis of this litter says that I will be applying 109 lbs of nitrogen TKN per ton for a total of 218 lbs to the acre. In addition the sunn hemp will provide nitrogen as well. Is this an accessive amount of nitrogen, if so what is a better application rate while still utilizing the chicken litter or a is a different fertilizer recommended all together. Lastly, I want to follow this summer forage with a winter forage mix to accoplished both grazing and preparing this field for a hay field in the spring. Shold I fertilize again and with what and at what rate. The winter mix will contain triticale, peas, radish and collards. Thanks Jess KIllen L


1 Response

The nitrogen content of this poultry litter is very high. I have not seen poultry litter with nitrogen values that high. Regardless, not all of the nitrogen in poultry litter is available in one growing season. Often analysis reports will break down the actual percentage that might be expected to be available. The ammonium and nitrate forms of nitrogen are readily available but the organic portion, which makes up the majority of nitrogen content in poultry litter needs to mineralize to an inorganic form to be available to plants. Mineralization depends upon soil microbes, soil temperature, soil pH and soil moisture primarily plus some other factors, so possibly between 30 to 50% might be mineralized in the first year of application.
Click on the link provided to get more information about using poultry litter:
So,if the analysis is correct, yes this is alot of total nitrogen but only a portion of it will be available for your summer annual crops. Nitrogen use and efficiency is highly dependent upon the weather. Nitrate toxicity/poisoning is a concern with excessive nitrogen fertilization (typically 150 + lbs of actual N/acre) and drought conditions. Take precautions if we enter a hot, dry spell where the forages are stressed and not growing normally.
Your winter annuals have some good nitrogen scavengers in the mix with triticale radish and collards. I don't believe you will need any additional fertilizer, but you could always take a soil sample to check on P and K levels. Since the intent is to go to a hay field, make sure soil pH is at least 6.5 before spring planting.
If you want to discuss any of this in more detail, give me a call at the Wayne County Extension office at 330-264-8722.
Rory Lewandowski