(248)__Phryma leptostachya, commonly known as lopseed;

(249)__Phyllodoce caerulea, commonly known as mountain heath;

(250)__Physalis pruinosa, commonly known as hairy ground-cherry;

(251)__Pinguicula vulgaris, commonly known as common butterwort;

(252)__Platanthera flava, commonly known as pale green orchis;

(253)__Platanthera leucophaea, commonly known as prairie white-fringed orchid;

(254)__Platanus occidentalis, commonly known as sycamore;

(255)__Poa fernaldiana, commonly known as wavy bluegrass;

(256)__Poa glauca, commonly known as white bluegrass;

(257)__Podostemum ceratophyllum, commonly known as threadfoot;

(258)__Polemonium vanbruntiae, commonly known as Jacob's ladder;

(259)__Polygala cruciata, commonly known as marsh milkwort;

(260)__Polygala senega, commonly known as Seneca snakeroot;

(261)__Polygonum douglasii, commonly known as Douglas' knotweed;

(262)__Polygonum tenue, commonly known as slender knotweed;

(263)__Potamogeton confervoides, commonly known as alga-like pondweed;