Identifying Alfalfa Varieties Best Suited to Pasture Rejuvenation

Background

Alfalfa content of perennial pastures is known to decline over time. Many producers choose to rejuvenate pastures through the addition of alfalfa, but the soil microbial community of the existing pasture plays a role as to how successful rejuvenation can be and can inhibit future plant growth.

Objectives

• Determine which alfalfa varieties respond positively to soil microbes from older alfalfa fields and can thus be recommended for pasture rejuvenation.

What they will do

This researcher wants to test 19 different alfalfa varieties to see which may be most suited for rejuvenation. Soil samples (which will contain different soil microbes) will be collected from 12 producer farms that have declining alfalfa stands. In the lab they will grow each alfalfa variety in the each of the different soil samples as well as a sterile soil. After 3 months alfalfa will be harvested, and forage productivity and root biomass will be evaluated.

Implications

This project might give a clue as to why sometimes pasture rejuvenation fails. It will provide recommendations as to which alfalfa varieties are more likely to thrive in existing stands and which ones to avoid.