An inventory of herbivorous insects associated with Eurasian milfoil in Otsego Lake , summer 1999

Earlier studies have indicated that Eurasian milfoil is not as large a problem in Otsego Lake as in other water bodies (Minor, 1997). It has been hypothesized that Acentria ephemerella. present in Otsego Lake, controls Eurasian milfoil (Merrifield and Hannan, 1988). In its larval stage Acentria grazes on milfoil, hindering its growth. In the summer of 1997 Miner (1998) studied meroplankton found to inhabit Myriophyllum spicatum focusing on Acentria. Her conclusion was that Acentria was found in insignificant numbers and therefore was not the cause for the low nuisance rate of mi1foil in Otsego Lake (Minor, 1998). However, herbivorous chironomid flies (midges) are quite abundant and may playa role in limiting milfoil. To better understand the innocuous nature of milfoil in Otsego, all invertebrates found on milfoil were determined and population estimates were estimated.