Looking for a proven way to reduce fertilizer costs and improve soil health? Poultry litter has proven to be one of the most effective, affordable alternatives to synthetic, salt-based fertilizers. Peer-reviewed studies across the Midwest show that manure-based systems not only maintain yields and reduce dependence on synthetics, but also improve long-term soil fertility, and boost profit margins. Here's the research farmers should know.
What decades of research say about poultry litter fertilizer
12-year South Dakota trial
This poultry litter trial evaluated nutrient management across a corn-soybean rotation on Midwestern soils. Over a dozen years, plots fertilized with turkey manure consistently outperformed synthetic treatments in soil health and nutrient retention.
- +25% increase in soil organic matter vs. synthetics
- Improved soil structure and water infiltration capacity
- Stabilized soil pH without the need for additional lime
- Informed phosphorus management practices for the Upper Midwest
20-year Iowa State study
This landmark study tracked the performance of poultry litter on continuous corn and corn-soy rotations over two decades. It's one of the most economically compelling head-to-head trials against synthetic nitrogen.
- +25% higher yields in continuous corn vs. UAN
- $50–$80/acre more profit after application — even with transport
- Higher nitrogen retention and slower-release nutrient availability
- Significantly better particulate organic matter in manure-treated soils
Read Iowa State's poultry litter study →
Meta-analysis of 116 trials
Across 116 peer-reviewed trials globally, poultry and turkey litter proved to be an effective organic fertilizer, particularly in diversified and corn-based cropping systems.
- Increased nutrient uptake efficiency vs. synthetic NPK blends
- Improved soil microbial activity and structure over time
- Higher long-term ROI in manure systems, particularly in low-rainfall or marginal soils
- Broad validation across climates, crop types, and soil types
Explore poultry litter fertilizer trials →
Rodale's 40-year farming systems trial
Rodale's benchmark organic-vs-conventional trial included poultry litter in the organic fertility program. Over four decades, it's proven that manure-fed systems perform best when it matters most.
- 30% better yields during drought years vs. synthetic systems
- Lower input costs with no reduction in long-term productivity
- More resilient soil biology and carbon retention
- Maintained fertility through variable weather and stress
Rodale's organic vs synthetic comparison →
You don't have to overhaul your whole system. Most farmers in these studies started small — trialing poultry litter on a few fields. The results added up: stronger soil, lower input costs, and more resilient yields.
So if you're looking to reduce synthetic dependence, rebuild organic matter, or just stabilize your input costs, we can help.