It is more common now than when Europeans first arrived in North America. It can grow in areas subject to seasonal flooding or brackish water. It is not particularly sensitive to soil moisture, although it does not grow in desert or arid conditions. It grows in a wide variety of soil types, and soil pH from 6.0 (acidic) to 7.9 (moderately alkaline). Older vines on substantial supports send out lateral branches that may be mistaken for tree limbs at first glance. The plants can grow as a shrub up to about 1.2 metres (3.9В ft) tall, as a groundcover 10вЂ“25В cm (3.9вЂ“9.8В in) high, or as a climbing vine on various supports. Toxicodendron radicans rarely grows at altitudes above 1,500В m (4,900В ft), although the altitude limit varies in different locations. rydbergii (western poison ivy) are found in western North America.

The plant is extremely common in suburban and exurban areas of New England, the Mid-Atlantic, and southeastern United States. It may grow as a forest understory plant, although it is only somewhat shade-tolerant. It also grows in exposed rocky areas, open fields and disturbed areas. It is normally found in wooded areas, especially along edge areas where the tree line breaks and allows sunshine to filter through. Caquistle or caxuistle is the Nahuatl term for the species. states East of the Rocky Mountains, as well as in the mountainous areas of Mexico up to around 1,500В m (4,900В ft). Toxicodendron radicans grows throughout much of North America, including the Canadian Maritime provinces, Quebec, Ontario, Manitoba, and all U.S. Seeds are spread mainly by animals and remain viable after passing through the digestive tract. Fruits are a favorite winter food of some birds and other animals. The berry-like fruit, a drupe, mature by August to November with a grayish-white colour. The yellowish- or greenish-white flowers are typically inconspicuous and are located in clusters up to 8В cm (3.1В in) above the leaves. It is dioeciou flowering occurs from May to July. Toxicodendron radicans spreads either vegetatively or sexually. It is frequently eaten by animals such as deer and bears. The urushiol compound in poison ivy is not meant as a defensive measure rather, it helps the plant to retain water. The milky sap of poison ivy darkens after exposure to the air. The vines develop adventitious roots, or the plant can spread from rhizomes or root crowns. Vines growing on the trunk of a tree become firmly attached through numerous aerial rootlets. Leaflet clusters are alternate on the vine, and the plant has no thorns. Each leaflet has a few or no teeth along its edge, and the leaf surface is smooth. The leaflets of mature leaves are somewhat shiny. Leaf color ranges from light green (usually the younger leaves) to dark green (mature leaves), turning bright red in fall though other sources say leaves are reddish when expanding, turn green through maturity, then back to red, orange, or yellow in the fall. radicans are trifoliate with three almond -shaped leaflets. as a trailing vine that is 10вЂ“25 centimetres (3.9вЂ“9.8В in) tall.as a shrub up to 1.2 metres (3В ft 11В in) tall.as a climbing vine that grows on trees or some other support.radicans, which can be found growing in any of the following forms all of which have woody stems: There are numerous subspecies and/or varieties of T. Toxicodendron radicans vine with typical reddish 'hairs.' Like the leaves, the vines are poisonous to humans. Toxicodendron radicans is commonly eaten by many animals, and the seeds are consumed by birds,but poison ivy is most often thought of as an unwelcome weed. The species is variable in its appearance and habit, and despite its common name it is not a true ivy (Hedera), but rather a member of the cashew family.

Poison ivy Toxicodendron radicans, commonly known as eastern poison ivy or poison ivy, is a poisonous Asian and North American flowering plant that is well known for causing an itching, irritating, and sometimes painful rash in most people who touch it, caused by urushiol, a clear liquid compound in the plantвЂ™s sap.

Western poison ivy