Invasive Plants The species below are the most serious threats or worst offenders to our native ecosystems. Many have been designed as "Noxious Weeds" by the PA Department of Agriculture and are also a major concern to our agricultural community. SCIENTIFIC NAME COMMON NAME PLANT FORM NOTES PENNSYLVANIA FREQUENT AREAS PENNSYLVANIA OCCASIONAL / RARE AREAS Alliaria Petiolata Garlic Mustard Flower spreading in woodlands SE, SC, SW, NW NE Carduus Nutans Musk Thistle Flower PA Noxious Weed SE, SC, SW, NE, NC, NW - Cirsium Arvense Canada Thistle Flower PA Noxious Weed SE, SC, SW, NE, NC, NW - Cirsium Vulgare Bull Thistle Flower PA Noxious Weed SE, SC, SW, NE, NC, NW - Datura Stramonium Jimsonweed Flower PA Noxious Weed SE, SC, SW NE Galega Officinalis Goatsrue Flower PA Noxious Weed - SE Lythrum Salicaria Purple Loosestrife Flower PA Noxious Weed SE SC, SW, NE, NC, NW Microstegium Vimineum Japanese Stilt Grass Grass Annual Grass SE SC Phragmites Australis Common Reed Grass wetland grass can form huge colonies SE SC, SW, NE, NW Polygonum Cuspidatum Japanese Knotweed Flower difficult to control SE SC, SW, NE, NW, NC Sorghum Bicolor Drummondii Shattercane Grass grass; difficult to control SE SC, NC Sorghum Halepense Johnson Grass Grass grass; pa noxious weed; spread by root and seed SE SC, SW, NE, NW Elaeagnus Umbellata Autumn Olive Shrub escaped from plantings; rapidly spread by birds SE, SC SW, NE, NW Lonicera Maackii Amur Honeysuckle Shrub escaped from plantings; seeds spread by birds - SE, SC, NW Lonicera Morrowii Morrow's Honeysuckle Shrub escaped from plantings; seeds spread by birds SE, SC, SW NE, NC, NW Lonicera Standishii Standish Honeysuckle Shrub escaped from plantings; seeds spread by birds - SE Lonicera Tatarica Tartarian Honeysuckle Shrub escaped from plantings; seeds spread by birds SE, SC, SW NE, NW Rosa Multiflora Multiflora Rose Shrub seeds spread by birds; PA noxious weed SE, SC, SW NE, NC, NW Acer Platanoides Norway Maple Tree commonly planted and escaped; wind spreads prolfic SE SE, SW Ailanthus Altissima Tree-of-Heaven Tree invasive in many states; wind spreads prolific seeds SE, SC SW Celastrus Orbiculatus Oriental Bittersweet Vine escaped from cultivation; seeds spread rapidly by birds SE, SC, SW NE, NW Lonicera Japonica Japanese Honeysuckle Vine - SE, SC SW, NE Polygonum Perfoliatum Mile-A-Minute Vine Vine range expanding; PA noxious weed SE SW Pueraria Lobata Kudzu Vine PA noxious weed SE SW Pennsylvania Distribution Key: SE=Southeast, SC=South Central, SW=Southwest, NE=Northeast, NC=North Central, NW=Northwest. Source: "Invasive Plants in Pennsylvania" - DCNR Return to Southampton Watershed Association home page. Site design by DiAnn Ohama.