| Zm | Zostera marina (eelgrass) |
| Rm | Ruppia maritima (widgeon grass) |
| C | Chara sp. (muskgrass) |
| Cd | Ceratophyllum demersum (coontail) |
| Ec | Elodea canadensis (common elodea) |
| Ed | Egeria densa (water-weed) |
| Hd | Heteranthera dubia (water stargrass) |
| Hv | Hydrilla verticillata (hydrilla) |
| Ms | Myriophyllum spicatum (Eurasian watermilfoil) |
| N | Najas spp. (naiad) |
| Nfl | Najas flexilis (northern naiad) |
| Ngr | Najas gracillima (slender naiad) |
| Ngu | Najas guadalupensis (southern naiad) |
| Nm | Najas minor |
| Pcr | Potamogeton crispus (curly pondweed) |
| Pe | Potamogeton epihydrus (leafy pondweed) |
| Ppc | Potamogeton pectinatus (sago pondweed) |
| Ppf | Potamogeton perfoliatus (redhead-grass) |
| Ppu | Potamogeton pusillus (slender pondweed) |
| Tn | Trapa natans (water chestnut) |
| Va | Vallisneria americana (wild celery) |
| Zp | Zannichellia palustris (horned pondweed) |
| U | Unknown species composition |
| Citizens Field Observation |
| U.S. EPA |
| Essex Community College |
| Harford Community College |
| MD. Dept. of natural Resources |
| Patuxent River Park |
| U.S. Geological Survey |
| VIMS Field Survey |
 | 1994 SAV Beds |
Each bed is identified with an unique two letter (AA-ZA, AB-ZB, etc.) and one number (1-4) designation. The numbers represent the density classification discussed in the text and Figure 8, i.e., 1 = <10%; 2="10-" 40%; 3="40-70%;" 4="70-100%."