Complementary practices for more feed and better environmental outcomes on high-production dairy farms
Introduction
As the demand for food and agricultural land grows, there's an increasing need to produce agricultural goods more intensely and sustainably. This is especially complicated in the dairy sector, where the feed must closely match the nutritional needs of dairy herds. We designed this study to explore new ways to sustainably increase dairy production in BC and reduce importing feed and nutrients onto farms.
We created and tested four management scenarios. We called these management scenarios 'Farmlets' because they represent real and aspirational farms. Each Farmlet stacks an additional Beneficial Management Practice (BMP), where 'Farmlet 1' was conventional practices (no BMPs) and 'Farmlet 4' included three key BMPs all at the same time.
The goal of our research was to boost the production of silage corn and perennial grass while also reducing the negative environmental effects of intensive crop production. We studied how these management scenarios affected crop yield and N and P recovery. We also used computer software to model and understand how much feed the cows would consume, how much milk they would produce, and the amount of nutrients they would excrete within each Farmlet. This method of research helps us understand complex farming systems and how to develop new technologies without the risk of unintended consequences.
About this Brief
This brief was prepared by the BC Food Web team with the help of Carson Li, Derek Hunt, and Shabtai Bittman, and is based on the following scientific journal article:
Li, C., Hunt, D., Koenig, K., Smukler, S., & Bittman, S. (2021). Integrated farm management systems to
improve nutrient management using semi-virtual Farmlets: agronomic responses. Environmental
Research Communications, 3(7). https://doi.org/10.1088/2515-7620/ac13c6
Key Findings
- Injection of separated manure sludge near the corn root zone eliminated the need for starter nitrogen (N) and phosphorus (P) fertilizer, cutting annual P application in half with no negative effects on yield.
- Intercropping Italian ryegrass with silage corn as a relay crop can provide additional high quality feed while reducing nitrogen leaching.
- Summertime irrigation and addition of nitrification inhibitors to manure before application can increase crop yield and N recovery of silage corn and perennial grass substantially.