Michigan Holly

(Ilex verticillata: Aquifoliaceae)

Description: Michigan Holly is a medium sized shrub not normally growing taller than 12 feet and usually about 6 to 8 feet tall and 3 to 5 feet wide. It has densely branched stems that grow into a round crown and flower in May and June with small yellow-white flowers. The fruits are highly distinguishable and grows in bright red clusters of small berries, forming in September and October and persisting into mid-winter (Current Reflections, 2001). Michigan Holly (also known as Winterberry) is dioecious, so both male and female plants are needed for fruit production (MSU Extension, 2001) and only females bear fruits.

A mature female in winter

A mature female in spring

Geographic Range: Michigan Holly is found throughout Eastern and Central North America, but does not grow well in the West, Southwest, or Lower Midwest because of dry winds and heat (Arborquest, 2001).

Habitat Requirements: Michigan Holly is found naturally in wetlands and will tolerate standing water or swamps, however, it prefers to grow in well-drained, acidic, damp, loamy or sandy soils and full or partial sun (Arborquest, 2001).

Distribution on the Preserve: Michigan Holly is observed primarily near the shoreline of Kelly Lake in the northwest corner of the preserve.

Status on the preserve: Due to the seasonal nature of Michigan Holly's flowers and fruits, this plant is extremely difficult to identify during the late winter and early spring seasons, making the census of Michigan Holly difficult. No population densities or successional models for the Michigan Holly have been determined at the preserve, but hopefully the holly will be censused as soon as time and the seasons allow.

Literature Cited:

Arborquest.com. "Ilex verticillata 'Red Sprite'." 2001. 26 April 2001. http://www.arborquest.com/SPdetail.cfm?sp=ILVERE

Current Reflections. "Shoreline Plant Profiles: Winterberry or Michigan Holly (Illex Verticillata)." 2001. Tip of the Mitt Watershed Council. 26 April 2001. http://watershedcouncil.org/news74.htm

Michigan State University Extension. "Home Horticulture: Ilex verticillata--Michigan Holly, Winterberry." 2001. 26 April 2001. http://www.msue.msu.edu/msue/imp/mod03/01700501.html

Contributors: Jonathan Atwell, Meribeth Huizinga, Joseph Veldman