There are many factors during grass and alfalfa production and ensiling that influence variability in haylage quality. Better management of forage quality variability can improve the accuracy and precision of delivering diets to dairy cattle. This summer 2020, we collected haylage samples at harvest from alfalfa-grass mixtures on seven New York dairy farms. The objective of our study is to identify the production factors that influence the variability in haylage quality at harvest. In the second phase of the trial, we will connect the variability at harvest to the silage variability at feedout, TMR variability, and changes in milk production.