 Hedge bindweed
Calystegia sepium L. R. Br.
Family: Convolvulaceae
Description and Life Cycle:
Hedge bindweed is a unique type of annual (clonal pseudo-annual)
and, therefore, is often referred to as a perennial. The parent
‘dies’ in the fall, but, prior to dying it produces rhizomes and
seeds that overwinter. The rhizomatous roots are elongated, but,
lack underground stolons. The stems twine, trail or climb to 3 m.
Plants in the Convolvulaceae family always twine from right to left,
which is opposite the course of the sun. The leaves are heart or
arrow-shaped with rounded or angled (not pointed) basal lobes.
Leaves attach to the stem with long stalks in an alternate
arrangement. The leaves are delicate and thin textured, measuring 5
– 10 cm long and 2.5 – 5 cm wide. Solitary flowers are borne on
square stalks from within the leaf axils. The showy white to deep
pink, trumpet shaped flowers are present from July to September, and
measure 4 – 7 cm long. The flowers fully expand during sunny days,
but, stay closed during dull weather. Seeds are produced in 1 cm
long capsules which split when mature. Each capsule contains 2 – 4
seeds, each measuring 5 mm long. The seeds are slightly roughened
and can be dull gray, brown or black coloured. Hedge bindweed is
intolerant of shade.
Note – Worldwide there are 25 Calystegia species. In
Canada two species are native. In the United States, 16 of their 17
species are native. The plants morphology is not clear, but, it is
known to readily hybridize. The geographic distributions of the
plant species merge and overlap, making it difficult to divide the
subspecies.
Biological Control Agents
References
Cranston, R., D. Ralph and B. Wikeem. 2005. Field guide to noxious and other selected weeds of British Columbia. Gov. of BC. 94 p.
Grieve, M. 1995. Bindweed, greater. A Modern Herbal, Botanical.com. November 27, 2006. http://botanical.com/botanical/mgmh/b/binweg39.html
Harris, P. 2005. Classical biological control of weeds biology of target weeds. Field and hedge bindweeds Convolvulus arvensis L. and Calystegia sepium (L.) R. Br. Gov. of Can., Agriculture and Agri-Food Canada. February 1, 2007. http://res2.agr.ca/lethbridge/weedbio/plant/convolvulus_e.htm
MFR staff observations and comments
Whitson, T. D., ed. 1992. Weeds of the west.
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