By Blake Jackson
Nitrogen application is a well-established practice for promoting perennial grass growth. However, optimizing its effectiveness requires a nuanced understanding of source, rate, timing, and placement – the tenets of the 4Rs of nutrient stewardship.
A Washington County field study delves into these factors to evaluate how different nitrogen sources and application methods influence forage tonnage. The goal is to equip producers with data-driven insights for economically beneficial nitrogen management.
While increased forage growth is typically observed with nitrogen application, this study explores the economic viability of this practice. It factors in hay market prices, the cost of nitrogen application, and the potential economic benefit of improved animal performance due to higher forage quality.
The research team compared the impact of two nitrogen sources – urea, the industry standard, and polymer-coated slow-release nitrogen. These were applied at varying rates and timings. The timing comparison included single applications at green-up, split applications following cutting, and a combined approach utilizing both slow-release and readily available nitrogen sources.
To ensure all plots had a level playing field, a comprehensive soil test was conducted. Based on the results, deficiencies in phosphorus and potassium, essential nutrients for plant growth, were addressed. Interestingly, soil pH, although slightly below the recommended range, was intentionally left unadjusted to mirror the conditions often encountered by real-world producers.
Beyond Nitrogen: A Holistic Approach to Forage Production
The study underscores the importance of addressing limitations beyond nitrogen for maximizing forage yield. Soil testing remains a critical tool to identify potential deficiencies in other essential nutrients.
Additionally, proper harvest timing plays a key role. Targeting the appropriate stage between boot and early heading ensures a desirable balance between forage quantity and quality.
Unusually wet and warm weather conditions may have influenced initial results. The timing of fertilizer application was strategically chosen to minimize nitrogen loss through volatilization.
The findings from this study will empower farmers to make informed decisions regarding the most cost-effective nitrogen management strategies for their specific operations. By carefully considering factors like soil fertility, harvest practices, and economic feasibility, producers can optimize forage production and achieve greater profitability.
Photo Credit: gettyimages-r-j-seymour
Categories: Pennsylvania, Crops, Hay & Forage