At the 2nd Annual Ravine Symposium, hosted by the Toronto Botanical Garden on November 3, UFORA’s Stephen Smith spoke about the importance of controlling invasive plants, with particular focus on dog-strangling vine (DSV).

These invasives don’t just out-compete and eliminate native species, Smith explained, they can dominate an area so comprehensively that forest regeneration no longer occurs. In some areas of the Don Valley, he added, DSV has crowded out new tree growth so thoroughly that those sites could eventually be treeless when the mature trees die of old age.

Smith said the best hope to get rid of this and other invasives is effective bio-control that shrinks them to manageable proportions, as has been achieved with purple loosestrife. He also described methods for tackling woody plants, such as common buckthorn and Norway maple, but warned that 100 percent elimination is an unrealistic ambition.

The best we can do is to study and understand the conditions that favour native plants, where to grow what, to learn and to adapt. Learn more about invasive exotic species found in southern Ontario here.