The distribution and abundance of aquatic macrophytes in Swan Lake and Middle Lake, Minnesota

Point intercept surveys were conducted on Swan Lake and Middle Lake, Minnesota to quantitatively assess aquatic macrophyte distribution and abundance. A sediment particle size analysis was conducted to determine if sediment particle size influenced sago pondweed (Stuckenia pectinata (L.) Borner) and wild celery (Vallisneria americana Michx.) distribution. Swan Lake had more macrophyte species than Middle Lake. Sago pondweed distribution was different between 2001 and 2002 in Middle Lake. Wild celery was only found in Swan Lake and its distribution was also different between sample years. The presence of sago pondweed was positively related to percentage of clay in Swan Lake sediments. The presence of wild celery was negatively related to the percentage of clay in the sediment. No relationship was found between sediment particle size and sago pondweed growing in Middle Lake.