Weed and algae ID guide
Pond weed and algae ID guide for Pennsylvania
Name the plant before you treat it. Every control choice, from grass carp to a permit application, depends on knowing exactly what is growing. These 20 pages cover the algae, submerged plants, floating plants and shoreline plants Pennsylvania pond owners ask about most, with the status, grass carp preference and permit notes for each.
Algae and cyanobacteria
Filamentous algaeAlgae: a natural part of every pond
Planktonic algaeAlgae: a natural part of every pond
Cyanobacteria (blue-green algae)Bacteria, natural at low levels
Chara (muskgrass)Algae: common in Pennsylvania ponds
Submerged plants
CoontailNative
ElodeaNative
Curly-leaf pondweedInvasive in Pennsylvania
Eurasian watermilfoilPennsylvania noxious weed
HydrillaPennsylvania noxious weed
Brittle naiadInvasive in Pennsylvania
Large-leaf pondweedNative
Floating plants
DuckweedNative
WatermealNative
SpatterdockNative
White water lilyNative
WatershieldNative
European water chestnutPennsylvania noxious weed
Shoreline (emergent) plants
CattailInvasive in Pennsylvania
Phragmites (common reed)Invasive in Pennsylvania
Purple loosestrifePennsylvania noxious weed
Not sure what you have? Penn State Extension's county offices help with identification. Photos are licensed from Wikimedia Commons or U.S. government sources; see Credits.