Alfalfa Stem Morphology and Yield Under Traditional Hay and Biomass Management Production Regimes.

Alfalfa stems have been proposed as a promising bioenergy feedstock, yet specific knowledge of stem characteristics that enhance bioenergy conversion is limited. We evaluated biomass-type and high quality hay-type alfalfas for gross stem morphology and yield under traditional hay (normal population density harvested at early bud) and biomass (decreased population density harvested at late flower) management regimes. Plots were established at two locations in a split plot design with harvest maturities as whole plots and combinations of population densities and germplasms as subplots.  Alfalfa samples were evaluated for morphological characteristics including stem length, diameter, total number of internodes, number of elongating internodes, and whole plot biomass yield.  Preliminary results indicate that both germplasm and harvest management regimes impact stem morphology and yield.