Wild celery is a herbaceous perennial. The tubers, leaves and seeds of this plant provide an extremely important food source for migrating waterfowl, particularly Canvasbacks (see section 5.3). It is most abundant in muddy fine-grained areas along the western and northern boundaries of the Bay (Figure 5.5 and Table 5.2), is fairly tolerant of water depth, and is commonly found in association with Chara spp. and Potamogeton spp. (Knapton and Petrie, 1999). Berst and McCrimmon (1966) ranked wild celery as the second most abundant species during their 1962 surveys of the Inner Bay. It apparently experienced a decline in abundance by 1976, followed by a south and west range expansion within the Bay during the 1990s (Figure 5.5). Knapton and Petrie (1999) reported that wild celery occupied over 40% more sampling stations in 1995 than in 1976 (Table 5.3). The spread has quite possibly been the result of water clarification by zebra mussel filtration and/or the continued deposition of fine-grained sediment in the western half of the Inner Bay (Knapton and Petrie 1999). Wild celery may also be expanding its range along the north shore east from Pottohawk to Bluff Point (Michael Bradstreet, personal communication).