Gibberellic acid application through broadcast dairy manure in perennial forages

Overview

This research investigates whether gibberellic acid can be combined with liquid dairy manure to improve haycrop re-growth compared to manure application alone. The approach leverages existing product labeling that permits gibberellic acid to be applied through center pivot and sprinkler irrigation systems, and tank-mixed with certain chemicals. By delivering the growth regulator directly through liquid dairy manure, the research seeks to dramatically reduce custom application costs and eliminate additional field traffic on dairy operations. The outcome could provide dairy farmers with a more efficient nutrient and forage management strategy that integrates fertilization and growth enhancement into a single pass.

Technical specifications

Research approach:

• Field trial at the William H. Miner Agricultural Research Institute comparing multiple application methods
• Treatments include gibberellic acid delivered through liquid dairy manure, applied via sprayer before manure application, and applied via sprayer several days after manure application, alongside an untreated control
• Measurement of canopy cover, yield, and forage quality across all treatment plots
• Evaluation of grass and legume mixed perennial forages typical of northeastern dairy operations

Potential benefits for dairy operations:

• Reduced custom application costs by combining fertilizer and growth regulator delivery
• Decreased field traffic and soil compaction through fewer passes
• Improved forage re-growth and quality supporting dairy productivity

Technology readiness level

This is an early-stage field validation study (TRL 3-4). The active ingredient product is commercially labeled for certain application methods, but its effectiveness when delivered specifically through broadcast liquid dairy manure on perennial forages has not been validated. The proposed field trial will generate the first direct evidence of agronomic performance, compatibility, and economic value of this combined application approach under real-world dairy farm conditions.