Ep. 3 A Buckthorn in my side

Since joining FOTCSI I have had the chance to get out and explore the sub-watershed and the different communities in and around the Coves, Silver Creek Ravine and Euston Park.  Not unlike many, many, sites across southern Ontario the Coves sub-watershed has become inundated with the invasive species:  European Buckthorn (Rhamnus cathartica). 

To most, European Buckthorn looks like just another member of the forest community.  However Buckthorn represents a real threat to native species as it is rapidly pinching out available growing space, light and is seriously hindering the growth of seedling and saplings of important native plants in southern Ontario.

What unleashed this forest scourge? Environmental vanity. European Buckthorn’s original purpose for import was for use in gardens for it’s aesthetic value.Buckthorn is now #2 on the Ontario noxious plant list, and it’s potential to spread rapidly is very real as birds and animals that feed on the berries transport the seeds and promote the further growth, spread and germination of new Buckthorn. 

To locate Buckthorn here in London you don’t need to look very far; woodlots, fence lines, pastures and unused farmland are all very common locations to find patches and thickets full of Buckthorn.  Controlling and removing Buckthorn is dually important as the plant also acts a host for puccinia coronata, a fungi which causes a disease called crown rust in Oats. This may not be an immediate danger in urban setting but on agricultural land this could be potentially hazardous to the cereal crop.  All this considered it’s hard to believe European Buckthorn is still available at some nurseries.

To identify European Buckthorn invasions of your own neighborhood use these characteristics:

Size: Multi-stem shrub to a bushy small tree up to 6m tall

Leaves: Typically opposite (2 per node) in arrangement, oblong shape, with 2-4 strong veins arcing to the leaf tip from the midrib, may have fine teeth on leaf edge.

Stem: Individuals over a year old will develop thorns at tips of stems

Fruits: 5-6mm in diameter, black/purple in color

Flower: Green/yellow, clustered at base of leaves.