Aquatic vegetation monitoring allows to evaluate community evolution and to determine the potential of damages associated to these populations. The objective of this work was to identify the aquatic plants and infestation levels of each species in the Bariri reservoir in the state of São Paulo, Brazil. All the aquatic vegetation foci in the dam (194 points) were evaluated and marked with GPS equipment. The plants were identified and a visual estimate of the geographic value of the point (size of the area) and a proportional distribution of the plants in the focus were carried out. Fifteen macrophyte species were found vegetating in the Bariri dam. Due to the great diversity of the species found, those presenting infestation levels above 10% were considered to be the major ones. Therefore, the most important aquatic species were: Brachiaria mutica, Brachiaria subquadripara, Eichhornia crassipes and Typha angustifolia. Another species that may be considered prominent with an index between 5% and 10% and a good infestation potential was Enidra sessilis.
weed; assessment; monitoring; reservoir
