Five Points Trail Guide Sign 4: Alien Invasion!

[1]Invasive species are like bullies that try to slow down and stop the chain of succession in the ecosystem. One prominent invasive shrub in Five Points Forest is European Buckthorn (Rhamnus cathartica). TTLT and the stewards of the property actively remove Buckthorn every year. Buckthorn is greedy, staying green longer than native plants and stealing the sunlight! Buckthorn does not share space well either, growing quickly and forming patches where nothing else is allowed in. The black berries of this plant show up in the late summer and the seeds get spread around by birds. As it is gradually removed, we are seeing native species come in and grow, slowly healing the scar that Buckthorn has left on the landscape.

Garlic Mustard is an aggressive, invasive herb that is prevalent at the ground level. In the first year of its life, it grows in a cluster of leaves like a rosette, developing strong roots that will grow into a tall flowering plant with hundreds of seeds in year two. Dense stands of garlic mustard can produce more than 60,000 seeds per m2 and double in size every four years[2]. The seeds of this plant can be easily spread by people and animals. They can remain in the soil for many years and still be able to germinate. Al Driedger is a valuable resource in the fight against Garlic Mustard in Five Points Forest, relentlessly picking the plants every year before they flower. TTLT has also developed an “Adopt-a-Patch” program to tackle the removal of this invasive plant.

European Buckthorn
European Buckthorn berries (above), Garlic Mustard year one (below, left) and Garlic Mustard year two (below, right)
Garlic Mustard Year OneGarlic Mustard

[1] Image source: Credit Valley Conservation, King County and www.eattheweeds.com

[2] Retrieved from: http://www.invadingspecies.com/invaders/plants-terrestrial/garlic-mustard/