Persistent Differences in Two Forms of Spartina Alterniflora: A Common Garden Experiment

Tall— and short—form Spartina alterniflora plants were transplanted from the Delaware marsh to common garden plots during the summer of 1978 and irrigated with saltwater three times a week during that and each subsequent growing season. Nine years later plant biomass, culm height, density, and diameter and flowering frequency remained distinct. Underground regrowth reserves and root profiles likewise remained distinct for the two forms. Since the two growth forms had been living in the same environment for 9 yr and had retained many ological and physiological differences, some genetic control of the morphology and physiology of the two growth forms is highly probable.