Observation and Background:
Vinca minor is an invasive species considered a high priority for control; it is a woody evergreen flowering plant that is native to Europe (Darcy and Burkart 2002). Further, it belongs to the Apocynaceae family and is commonly known as periwinkle or myrtle; landscapers seek it for its good ground cover because it requires little maintenance and upkeep. Invasive species are problematic in Northern Ontario due to their adverse effects on the landscape, natural resources, and the economy; the introduction may be exploding causing for an overabundance of these species to be present (Kourtev et al. 1998). This is concerning since recently I have found that within the forests of Sault Ste Marie, Ontario Periwinkle is becoming more abundant in the forest understory. A forest close to my local university has shown to be largely impacted by this invasive evergreen plant species. Last year as a prong to my undergraduate thesis I had mapped out an area (see attached photo) and found that the number of Acer saccharum (sugar maple) saplings in the V. minor invaded forest understory where significantly less when compared to the uninvaded areas clearly indicating that V. minor plays a pivotal role in reducing or suppressing the growth of A. saccharum. Since V. minor is mycorrhizal I examined the patters of effects (Mycorrhizal (AM) dependency and feedback mechanisms) of AM and Non-AM fungi on A.Saccharum roots but my results were inconclusive. So I am wondering, what could explain why A. Saccharum saplings size is significantly reduced in areas invaded by V.minor and what has caused V.minor to rapidly multiply across the forest understory?
Consult:
The consultant I contacted for this observation was Kim Chapman, a Forest Ecologist at the Great Lakes Forestry Centre located in Sault Ste Marie Ontario. She has stated the following:
"Vinca minor is a recognized invasive species in Ontario (and elsewhere) and I’ve noticed it on the campus at Algoma University, and other areas around Sault Ste. Marie, where it can be abundant and appears to exclude other species (in addition to Acer saccharum). I’m not sure if V. minor is becoming more abundant in local forests or not, and am not aware of any studies that have shown this to be the case. The Darcy and Burkart (2002) study you cite shows that of the two mechanisms the researchers investigate to explain A. saccharum seedling suppression, shading, or competition for light, rather than allelopathy seems to be the main cause and it seems plausible to me that the dense mat-forming habit and evergreen nature of V. minor would drastically reduce light available to seedlings and be a strong above-ground competitor for space and light to A. saccharum seedlings. There may be below-ground competitive effects as well."
Kim Chapman
Forest Ecologist
Great Lakes Forestry Centre
1219 Queen Street East
Sault Ste. Marie, Ontario, P6A 2E5
Tel.: (705) 541-5626
kim.chapman@canada.ca
References:
Darcy AJ, Burkart M. C. 2002. Allelopathic potential of Vinca minor, an invasive exotic plant in
west michigan forests. Bios. 127-132.
Kourtev PS, Ehrenfeld JG, Huang WZ. 1998. Effects of exotic plant species on soil properties in
hardwood forests of new jersey. In Biogeochemical investigations at watershed,
landscape, and regional scales. Soil Biol Biochem. 2(3):493-501.
Additional Information on Vinca minor:
http://www.invadingspecies.com/invaders/plants-terrestrial/invasive-ground-covers/
Observations From Members 