Animal biomass resources in Arkansas include manure and poultry litter. For this resource assessment, animal manure has been calculated and presented on the basis of "dry tons per year per county" for each of the following animal categories and subcategories:
According to the USDA NASS 2002 Census data, the vast majority of cattle operations in Arkansas are for beef producers rather than dairy:
On average, dairy farms are larger than beef farms: herd sizes average 115 and 30 animals, respectively. On average, dairy cattle produce more manure than beef cattle: 2.4 and 1.3 tons/year/animal, respectively.
The foregoing reflects the facts that dairy cattle are, on average, larger than beef cattle, and that dairy farms tend to be larger than beef farms (although at an average of 115 animals per farm, dairy farm sizes in Arkansas are much smaller than typical dairy farms in most areas of concentrated dairy production elsewhere in the U.S.). Also, there are no concentrated beef feedlots in Arkansas.
Summary of cattle-derived biomass:
Open or download all livestock data in Excel format by clicking:
According to the USDA NASS 2002 Census data, 41.2% of State's swine farms are for breeding (the data does not differentiate between farrow-to-nursery, farrow-to-grower, farrow-to-finish, or other farrowing operations). The remaining swine farms (58.8%) are classified as "other swine" (the data does not differentiate between nursery-to-feeder, nursery-to-finish, feeder-to-finish, or other types of swine operations).
Basic statistics of swine farms and swine manure production in Arkansas:
Most of the swine operations in Arkansas utilize flush systems for manure removal from production barns; the effluent is mostly water (solids are typically less than 2% and often just a fraction of 1%) and is typically discharged into a holding basin or lagoon. As such, the manure is not collectible in solid form per se, although a portion of the material could be obtained through screening.
Thus, from a biomass resource perspective, at least some of the swine farms in Arkansas may be able to benefit from anaerobic digestion of the effluent (with subsequent biogas production and utilization). However, from a technical perspective this may entail modifications to the existing basins/lagoons to enable/optimize conditions for anaerobic digestion (and from an economic perspective such modifications would have to be compared to the potential benefits from biogas utilization on a case-by-case basis).
The following is a summary of swine biomass production in Arkansas:
The USDA NASS 2002 Census provides data for each of the basic subcategories of poultry production operations: broilers, layers, replacement pullets, and turkeys. Most poultry farms consist of one type or another (i.e., not mixed at the same location). For this assessment, manure production is calculated for each subcategory as excreted and on a dry matter basis. Litter production is also estimated using a generally accepted assumption for litter generation per bird of 2.14 pounds of litter as is per bird produced (note: actual litter generation per bird varies considerably based on a variety of factors).
The table summarizes the assessment results re the Arkansas poultry industry.
From a biomass collection and utilization standpoint, litter from broiler and turkey operations is readily collectible, and there are numerous potential uses in addition to the historical practice of land application as an organic fertilizer/soil amendment product. Manure/litter from layer/pullet operations typically has higher moisture content than broiler or turkey litter but is also collectible and potentially usable.