Evaluating the effects of ruminal incubation and abomasal enzymatic digestion on the germination potential of Bromus tectorum

Targeted grazing is a management strategy for fuel reduction and cheatgrass control in the Great Basin. However, concerns of cattle acting as endozoochorous seed dispersal agents of invasive grass species have been expressed. In vitro and in situ techniques of ruminal fermentation and enzymatic digestion were employed to evaluate seed mortality. Our results showed a nearly complete inhibition of germination after 36 hours in the rumen followed by 3 hours in the abomasum. Our results indicate cattle grazing cheatgrass-infested rangelands will not spread cheatgrass seed via excrement. Cheatgrass seeds consumed in the fall will have a slight lag in microbial degradation.