SEASONAL BIOMASS AND CARBOHYDRATE ALLOCATION IN A SOUTHERN-POPULATIONOF EURASIAN WATERMILFOIL

Seasonal biomass and carbohydrate allocation patterns of Eurasian wate rmilfoil (Myriophyllum spicatum L.) were evaluated to elucidate potent ial points in the seasonal phenological cycle for improved control. Eu rasian watermilfoil was sampled from outdoor 0.3 ha ponds in Lewisvill e, TX from January 1991 to December 1993 and analyzed for free sugars, starch and total nonstructural carbohydrates (TNC). Root crowns store d up to 30% TNC, followed by autofragments (25%), lower stems (22%), a nd upper stems and inflorescences (12%). Low levels of stored carbohyd rates occurred in July (1991), April (1992), and May (1993). Low level s of stored carbohydrates also were observed in October for all three years. Low points in carbohydrate storage might be exploited to improv e management of Eurasian watermilfoil.