**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** THIS PROJECT ALIGNS BEST WITH PROGRAM 3, PARTICULARLY 3A, B AND E. DESPITE THE IMPLEMENTATION OF BEST MANAGEMENT PRACTICES (BMPS) AND GROWER OPPORTUNITY ZONES (GOZS), ADVENTITIOUS PRESENCE (AP) IS OCCURRING AND NEGATIVELY IMPACTING THE COEXISTENCE OF ALFALFA MARKETS. FERAL POPULATIONS PRESENT AN ADDITIONAL CHALLENGE IN ALFALFA BECAUSE THEY CAN ACT AS BRIDGES AND REFUGES FOR GE GENES. THE GLYPHOSATE RESISTANCE (GR) GENE HAS BEEN DETECTED IN MANY ALFALFA FERAL POPULATIONS BUT LITTLE INFORMATION EXISTS ON ITS FREQUENCY (J-101 AND J-163 EVENTS) AND ON ITS IMPACT ON THE POLLINATORS, PESTS AND DISEASES, LIFE HISTORY CHARACTERISTICS AND POTENTIAL FOR INVASIVENESS OF THESE POPULATIONS. FILLING THESE KNOWLEDGE GAPS IS THE OVERALL GOAL OF THIS PROPOSAL. WE WILL (1) EXPAND THE GEOGRAPHICAL SURVEY OF FERAL POPULATIONS AND ESTIMATE THE CHANGE IN FREQUENCY OF THE GR GENE IN FERAL POPULATIONS; (2) QUANTIFY THE IMPACT OF THE GR GENE ON POLLINATORS, PESTS AND DISEASE AND ON LIFE HISTORY PARAMETERS OF FERAL ALFALFA, AND (3) PARAMETERIZE A POPULATION MATRIX MODEL FOR GR AND NON-GR ALFALFA. TO REACH THESE GOALS, WE WILL (1) REVISIT PREVIOUSLY VISITED FERAL POPULATIONS (CA, ID, WA) AND EXPAND THE SEARCH IN THESE AND OTHER STATES (WY, MT, KS AND WI); TEST FOR THE PRESENCE OF THE GR GENE AND PERFORM PCR AND QPCR TO OBTAIN THE FREQUENCY OF THE J-101 AND J-163 EVENTS; (2) COMPARE POLLINATORS, PESTS AND DISEASE AND LIFE HISTORY PARAMETERS AND (3) DEVELOP POPULATION MATRIX MODELS TO QUANTIFY THE POTENTIAL FOR INVASIVENESS, BETWEEN GR STATUS AND ACROSS REGIONS.