The evergreen climbing vine Hedera helix, or more commonly known as English Ivy, of the Araliaceae family grows naturally in Europe and western Asia (Swearingen, 2013). It was introduced into North America as an ornamental and is still widely used today as such, being used in winter decorations including those associated with Christmas (Ghazanfar, Osborne & Hall, 2013). This vine may grow up to 30 metres tall (Klinkenberg, 2013). For this reason, English Ivy is considered to be invasive in Australia, New Zealand and western USA (Ghazanfar et al., 2013). Nonetheless, English Ivy does not pose a threat to healthy trees as it is not parasitic (Ghazanfar et al., 2013). Plus, its growth can be kept under control via consistent pruning (Brand, 2001).
English Ivy has long woody vines that cling to vertical structures such as trees or buildings for support to grow upwards. This means that this plant prefers the partial shady conditions offered by such establishments (Brand, 2001). If the ivy is present where there are no upright provisions for it, the plant serves to provide groundcover instead (Pascoe, 2011). During the winter months, English Ivy provides food and shelter for blackbirds (Ghazanfar et al., 2013). However, it lacks the ability to survive in very cold conditions and its leaves will drop due to desiccation upon exposure to strong winds (Brand, 2001).
The English Ivy plant has two distinctive shapes of evergreen leaves corresponding to growth type, both ranging from 4 to 10 centimetres in length (Ghazanfar et al., 2013; Klinkenberg, 2013). Young leaves are palmately lobed, which means 3-5 lobes exude from a central point while the adult leaves entirely lack lobes and are heart shaped, or also known as cordate shaped (Pascoe, 2011; Kling, Hayden & Potts, 2005). The juvenile stage is also characterized by stems having roots as adult ivy plants do not have roots; instead, terminal flowering shoots indicates the plant’s maturity (Ghazanfar et al., 2013). Flowering occurs in the late summer to early fall months (Swearingen, 2013). Flowers are small, ranging from 3 to 5 centimetres wide, are yellow-green in colour and umbel shaped (Pascoe, 2011). These flowers get pollinated by wasps and moths and are a vital source of nectar for bees when other sources are depleted (Ghazanfar, 2013). English Ivy does produce fruits. These berries are round, 6 to 9 millimetres in diameter and blue-black in colour and contain 2 to 5 seeds (Klinkenberg,2013; Pascoe, 2011; Ghazanfar, 2013). The fruits attract insects, which are then by the blackbirds (Ghazanfar, 2013).
Brand, M. (2001). English Ivy. University of Connecticut plant database. Retrieved from http://www.hort.uconn.edu/plants/h/hedhel/hedhel1.html
Ghazanfar, S., Osborne, J., Hall, T. (2013). Hedera helix (common ivy). Kew Botanical Gardens. Retrieved from http://www.kew.org/plants-fungi/Hedera-helix.htm
Kling, G., Hayden, L., Potts, J. (2005). Botanical Terminology. University of Illinois. Retrieved from http://woodyplantstutorial.nres.illinois.edu/
Klinkenberg, B. (2013). Hedera helix L. Electronic atlas of the flora of British Columbia. Retrieved from http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Hedera%20helix
Pascoe, M. (2011). Hedera helix (English Ivy). World plants database. Retrieved from http://www.canadaplants.ca/index.php
Swearingen, J. (2013). English ivy. Invasive Plant Atlas of the United States. Retrieved from http://www.invasiveplantatlas.org/subject.html?sub=3027