Pine, loblolly _P. taeda_ L. Pine, lodgepole _P. contorta_ Dougl. Pine, longleaf _P. palustris_ Mill. Pine, Monterey _P. radiata_ D. Don. Pine, pinyon _P. edulis_ Engelm. Pine, ponderosa _P. ponderosa_ Laws. Pine, shortleaf _P. echinata_ Mill. Pine, slash _P. elliotti_ Engelm. Pine, sugar _P. lambertiana_ Dougl. Pine, white _P. strobus_ L. Poison ivy _Rhus radicans_ L. Poison oak _Rhus diversiloba_ T. & G. Pokeberry _Phytolacca americana_ L. Pondweed _Potamogeton_ sp. Poplar _Populus_ sp. Poplar, balsam _Populus balsamifera_ L. Prunes _Prunus_ sp. Ragweed _Ambrosia_ sp. Raspberries _Rubus_ sp. Red heart fungus _Fomes_ sp. Redwood _Sequoia sempervirens_ (D. Don.) Endl. Retama _Retama_ sp. Sago pondweed _Potamogeton pectinatus_ L. Saguaro cactus _Carnegiea gigantea_ (Engelm.) Britt. & Rose Salmonberries _Rubus spectabilis_ Pursh. Sawgrass, tall _Cladium_ sp. Screwbean _Prosopis_ sp. Serviceberries _Amelanchier_ sp. Skunk cabbage _Symplocarpus foetidus_ (L.) Nutt. Smartweed _Polygonum_ sp. Snowberries _Symphoricarpos_ sp. Sorghum _Sorghum_ sp. Spruce _Picea_ sp. Spruce, Engelmann _Picea engelmannii_ Parry Spruce, Sitka _Picea sitchensis_ (Bong.) Carr. Strawberries _Fragraria_ sp. Sumac _Rhus_ sp. Sunflower _Helianthus_ sp. Sweetgum _Liquidambar styraciflua_ L. Sycamore _Platanus_ sp. Tamarac _Larix laricina_ (Du Roi) K. Koch Tulip-poplar _Liriodendron tulipifera_ L. Tupelo _Nyssa sylvatica_ Marsh. Virginia creeper _Parthenocissus quinquefolia_ L. Walnut _Juglans_ sp. Water stargrass _Heteranthera dubia_ (Jacq.) MacM. Wax-myrtle _Myrica cerifera_ L. Wheat _Triticum_ sp. Widegon grass _Ruppia maritima_ L. Wild celery _Vallisneria americana_ Michx. Willow _Salix_ sp. Willow, black _Salix nigra_ Marsh. Yucca _Yucca_ sp. Invertebrates Referred to in Text: