Plants & Trees Encyclopedia

Pumpkin — Pumpkin is a gourd-like squash of the genus Cucurbita and the family Cucurbitaceae (which also includes gourds). It can refer to either species Cucurbita pepo or Cucurbita mixta, and sometimes to a specific variety of either the species Cucurbita maxima or Cucurbita moschata. Since some squash share the same botanical classifications as pumpkins, the names are frequently used …

Primrose — Primula is a genus of 400-500 species of low-growing herbs in the family Primulaceae. They include primrose, auricula, cowslip and oxlip. Many species are grown for their ornamental flowers. They are native to the temperate Northern Hemisphere, south into high altitude tropical mountains in Ethiopia, Indonesia and New Guinea, and are also found in temperate southern South America. …

Potato — Potato is the term which applies either to the starchy tuberous root vegetable crop from the perennial plant Solanum tuberosum of the Solanaceae, or nightshade, family, or to the plant itself. Potato is the world’s most widely grown tuber crop, and the fourth largest food crop in terms of fresh produce — after rice, wheat, and maize (corn). …

Poppy — A poppy is any of a number of showy flowers, typically with one per stem, belonging to the poppy family. They include a number of attractive wildflower species with showy flowers found growing singularly or in large groups; many species are also grown in gardens. Those that are grown in gardens include large plants used in a mixed …

Poplar, White — Populus alba (White Poplar) is a species of poplar, most closely related to the aspens (Populus sect. Populus). It is native from Spain and Morocco through central Europe (north to Germany and Poland) to central Asia. It grows in moist sites, often by watersides, in regions with hot summers and cold to mild winters. It is a …

Poplar, Lombardy — Black poplar (Populus nigra) is a species of poplar in the cottonwood (Aegiros) section of the genus Populus, native to Europe, southwest and central Asia, and northwest Africa. It is a medium-sized to large deciduous tree, reaching 20-30 m (rarely 40 m) tall, with a trunk up to 1.5 m diameter. The leaves are diamond-shaped to triangular, …

Pomegranate — The Pomegranate (Punica granatum) is a fruit-bearing deciduous shrub or small tree growing to 5–8 m tall. The pomegranate is native to the region from Afghanistan, Pakistan, and Iran to the Himalayas in northern India and has been cultivated and naturalized over the whole Mediterranean region and the Caucasus since ancient times. It is widely cultivated throughout Armenia, …

Pokeweed — The pokeweeds, also known as poke, pokebush, pokeberry, pokeroot, polk salad, polk sallet, inkberry or ombú, comprise the genus Phytolacca, perennial plants native to North America, South America, East Asia and New Zealand. Pokeweed contains phytolaccatoxin and phytolaccigenin, which are poisonous to mammals. However, the berries are eaten by birds, which are not affected by the toxin because …

Poison Sumac — Poison sumac (Toxicodendron vernix or Rhus vernix) is a woody shrub or small tree growing to 7 m (20 ft) tall. All parts of the plant contain a resin called urushiol that causes skin and mucous membrane irritation to humans. When burned, inhalation of the smoke causes diarrhea and other internal irritations. The head of the tree …

Poison Ivy — Toxicodendron radicans (syn. Rhus toxicodendron, Rhus radicans; Poison ivy) is a plant in the family Anacardiaceae. The name is sometimes spelled “Poison-ivy” in an attempt to indicate that the plant is not a true Ivy (Hedera). It is a woody vine that is well known for its ability to produce urushiol, a skin irritant that causes an …