UMass Extension Weed Herbarium
| Common Name | Scientific Name | Family Name | |
|---|---|---|---|
| paintbrush, yellow | see - hawkweed | ||
| panicgrass, round-fruited | Dichanthelium sphaerocarpon | Poaceae (Graminae) - Grass Family | |
| panicum, fall | Panicum dichotomiflorum | Poaceae (Graminae) - Grass Family | |
| pansy, field | see - violet, field | ||
| pansy, wild | see - violet, field | ||
| parsnip, field | see - parsnip, wild | ||
| parsnip, wild | Pastinaca sativa | Apiaceae (Umbelliferae) - Carrot Family | |
| paspalum | Paspalum setaceum | Poaceae (Graminae) - Grass Family | |
| pearlwort, birdseye | Sagina procumbens | Caryophyllaceae - Pink Family | |
| pearly-everlasting | Anaphalis margaritacea | Asteraceae (Compositae) - Aster or Sunflower Family | |
| peavine, everlasting | Lathyrus latifolius | Fabaceae (Leguminosae) - Pea or Bean Family | |
| pennycress, field | Thlaspi arvense | Brassicaceae (Cruciferae) - Mustard Family | |
| peppergrass, field | see - pepperweed, field | ||
| peppergrass, wild | see - pepperweed, Virginia | ||
| pepperweed, field | Lepidium campestre | Brassicaceae (Cruciferae) - Mustard Family | |
| pepperweed, Virginia | Lepidium virginicum | Brassicaceae (Cruciferae) - Mustard Family | |
| piemaker | see - velvetleaf | ||
| pigeon berry | see - pokeweed, common | ||
| pigweed, livid | Amaranthus lividus | Amaranthaceae - Amaranth Family | |
| pigweed, redroot | Amaranthus retroflexus | Amaranthaceae - Amaranth Family | |
| pigweed, spiny | see - amaranth, spiny | ||
| pilewort | Erechtites hieraciifolia | Asteraceae (Compositae) - Aster or Sunflower Family | |
| pimpernel, scarlet | Anagallis arvensis | Primulaceae - Primrose Family | |
| pineappleweed | Matricaria matricariodes | Asteraceae (Compositae) - Aster or Sunflower Family | |
| pinkweed | see - smartweed, Pennsylvania | ||
| plantain, broadleaf | Plantago major | Plantaginaceae - Plantain Family | |
| plantain, buckhorn | see - plantain, narrowleaf | ||
| plantain, common | see - plantain, broadleaf | ||
| plantain, dooryard | see - plantain, broadleaf | ||
| plantain, English | see - plantain, narrowleaf | ||
| plantain, narrowleaf | Plantago lanceolata | Plantaginaceae - Plantain Family | |
| poison ivy | Toxicodendron radicans | Anacardiaceae - Cashew Family | |
| poke | see - pokeweed, common | ||
| pokeberry | see - pokeweed, common | ||
| pokeweed, common | Phytolacca americana | Phytolaccaceae - Pokeweed Family | |
| poor man's weatherglass | see - pimpernel, scarlet | ||
| porcelainberry | Ampelopsis brevipedunculata | Vitaceae - Grape Family | |
| portulaca , wild | see - purslane, common | ||
| potato bean | see - groundnut | ||
| purpletop | Tridens flavus | Poaceae (Graminae) - Grass Family | |
| purslane, common | Portulaca oleracea | Portulacaceae - Purslane Family | |
| pursley | see - purslane, common | ||
| pussytoes, field | Antennaria neglecta | Asteraceae (Compositae) - Aster or Sunflower Family |