Carrot Breeders (IMAGE) American Society of Agronomy Caption Carrot Breeder Philipp Simon (USDA-ARS, Madison WI) and graduate student Charlene Grahn explain their selection for stronger and more vigorous tops to improve carrot competition with weeds and ease of mechanical harvest. This complex trait is important for both conventional and organic production. Credit Micaela Colley / Organic Seed Alliance. Usage Restrictions Please use with story only. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.