Several vines, including English ivy, bittersweet, poison ivy and Virginia creeper, may show up uninvited to your garden. Occasionally these invaders are welcome guests. However, if they require removal, positively identify them first. Some plants may merely be a nuisance while others are potentially harmful. Accurately identify vines by considering the colour, shape and texture of the leaves, as well as by their flowers and fruits. When in doubt, don't touch the vine until you can positively identify it through a photograph.
Inspect the leaves for veins. English ivy, Persian ivy and Algerian ivy all have pronounced veins running through their leaves, as well as the characteristic lobed ivy shape. Their leaves may be dull or glossy green, or variegated with white margins. They are evergreen in many parts of the United States.
Count the leaflets. Virginia creeper (Parthenocissus quinquefolia), Boston ivy or Japanese creeper (Parthenocissus tricuspidata), and poison ivy all have clusters of leaflets and are often confused for each other. Virginia creeper has five leaflets, while Boston ivy and poison ivy have only three. Poison ivy (Toxicodendron radicans) may grow as a shrub in some parts of the United States. The vines of this irritating plant are often fuzzy.
Look for changes in colour. Boston ivy, Virginia creeper and poison ivy all turn red, yellow or bronze in the fall. Wintercreeper euonymus (Euonymus fortunei) is evergreen, although some varieties may turn red or purple.
Feel the leaves. Japanese wisteria (Wisteria floribunda) produces shiny, smooth leaves while the ovoid leaves of the honeysuckle (Lonicera sp.) are somewhat leathery and may be bluish on the undersides. The long, dark green leaves of the trumpet-creeper (Campsis radicans) have toothed edges and a tropical look.
Measure the space between leaves. Some clematis, such as Jackmanii, produce elongated oval leaves sparsely placed on the vine. Others, such as the sweet autumn clematis, have small leaves that densely fill the vines. The leaves of the silver fleece flower (Polygonum aubertii) are dense and light green, according to the University of Missouri Extension.
The chemical uroshiol that causes unpleasant reactions is released through the leaves of poison ivy and remains active for up to two years. Touching an exposed pet, clothing or sporting equipment may cause a reaction.