This project gauged the advantages of a pastured poultry system on a traditional livestock ranch on the Wrights Mesa of Colorado near Norwood. The poultry were rotated through irrigated pastures historically hayed and grazed by cattle. The goal was to diversify economic opportunities that can be integrated into the existing operation.
There were no significant differences in soil nutrient status between plots grazed by poultry and those not grazed during the study. Except for iron, nutrients increased in both plots. The percentage organic matter and water infiltration rate did increase with the deposit of manure in the grazed plot. But there was no change in bulk soil density on the grazed plot before and after grazing.
Given the changes in just one year, the project team speculates that the pastured poultry management system, over time, would improve soil fertility and structure. Meanwhile, the drought and limited irrigation water precluded assessing the effects of the pastured poultry on forage production.
• Assess the effects, positive or negative, of a pastured poultry production system on a traditional haying and grazing operation
• Determine whether the two production systems are complementary
• Assess whether soil properties and forage production are influenced by the pastured poultry system
• Expose traditional livestock ranchers to new marketing opportunities while fertilizing pastures naturally and sustainably
The experiment began June 1, 2002, with 75 Cornish cross chickens placed on pasture in a 10-foot by 12-foot pen moved daily and rotated through ½ acre every six weeks. Seventy-five more Cornish cross chickens were placed on the same half acre in mid August and rotated under the same grazing regime.
Baseline soil data were collected ahead of the first chicken release. The drought and lack of irrigation water precluded collection of forage data as planned. Cattle and horses were allowed to graze the pastures through winter 2002, and final soil samples were collected in spring 2003. No chemical fertilizers were applied to the pastures in 2002 or 2003.
For the experiment, the pasture was divided in two plots, one grazed by poultry and the other not grazed. The soils in each were sampled for pH, salts, lime, organic matter and several nutrients as well as for bulk density, water infiltration rate and water-holding capacity.
The 2002 baseline data showed significantly lower organic matter, higher bulk density and a slower water infiltration rate in the plot planned for poultry grazing than in the adjacent control plot, this despite a uniform soil texture (clay loam) across both sites. (The cause of the differences may have been high farm equipment traffic years earlier in the grazed plot.)
After the poultry grazed, the differences in organic matter and water infiltration rates were nullified, while the differences in bulk density increased, the latter owing to either sampling error or trampling by cattle and horses.
In both plots, all measured soil nutrients, except for iron, increased the second year after the grazing.
BENEFITS OR IMPACT ON AGRICULTURE
This two-year soil study hints at soil benefits from rotational grazing of poultry on irrigated grass and legume pasture. The chickens grazed the plants and were supplemented with grain. The deposition and distribution of their manure increased the soil matter in the soil, which, in turn, increased the water infiltration rate.
“It is probable,” says the project’s final report, “that this management system over time would significantly improve soil fertility and soil structure.”
None reported, although a nearby producer had asked questions about the project.
REACTIONS FROM PRODUCERS
Measurable changes in soil chemical and physical properties can take many years to manifest, especially with management or environmental changes. Multi-year studies are necessary to see trends or significant changes in soil quality indicators. Collection of a sufficient number of statistically significant random samples and replication of treatments needed to eliminate experimental error and reduce the likelihood of false or premature conclusions requires more time and money than was available for this study.