Flora of Pennsylvania

Ambrosia trifida gallery

Highly allergenic species commonly found in disturbed soils

Great Ragweed Gallery

Flowers
Flowers
Brady's Run Park (Beaver Co)
by Mark Welchley on 08/02/2012
Plant form
Plant form
Boalsburg Creek (Centre Co)
by Maria Pavlova on 08/02/2021
Plant form
Plant form
Buffalo Run Park (Centre Co)
by Maria Pavlova on 08/23/2022
Flowers & stem
Flowers & stem
Buffalo Run Park (Centre Co)
by Maria Pavlova on 08/23/2022
Three-lobed leaf
Three-lobed leaf
Matternville (Centre Co)
by Maria Pavlova on 09/02/2012
Flower & lobed leaves
Flower & lobed leaves
Matternville (Centre Co)
by Maria Pavlova on 09/02/2012
Stem
Stem
Centre Co
by Maria Pavlova on 09/02/2012
Whole plant
Whole plant
Buffalo Run Park (Centre Co)
by Maria Pavlova on 09/02/2024
Flowers & leaves
Flowers & leaves
Buffalo Run Park (Centre Co)
by Maria Pavlova on 09/02/2024
Flowers
Flowers
Brady's Run County Park (Beaver Co)
by Mark Welchley on 09/05/2012