Invasive Species

Invasive species of plants and wildlife occur across Planet Earth, and of course ‘invasive’ depends on ecological context, doesn’t it? Invariably this phenomenon is a result of human activity. Our actions have ecological consequences, often way beyond what we can anticipate…

One particular invasive species pest occurring globally is the Emerald Ash Borer beetle – most commonly known as the EAB. This insect is especially a problem and concern in North America where already (since the early 1990s) it has killed millions of native ash trees. Cornell Cooperative Extension of Greene County’s Agroforestry Resource Center has an invasive species programme (CRISP), and in particular it has its own EAB Task Force for educating and raising awareness of the infestation to local communities. Early-on in my residency I’ll be meeting with Marilyn Wyman who coordinates the local EAB Task Force. Whilst in dialogue with her I hope to learn more about the infestation and the measures being taken to try and prevent its spread further.

the EAB: it may be beautiful, but its a little beast!

Ash trees (Fraxinus spp.) are keystone species for entire ecosystems and so the threat of the EAB alone can potentially initiate the collapse of an ecosystem and subsequently the demise of valuable, biodiverse habitat. Whilst there is no known evidence of the EAB in the Siuslaw Model Forest specifically, there is always ‘just that chance’ it might be there… could there be a chance that Bug Cinema will encounter it?

There are no less than 300 species of Lepidoptera (moths and butterflies) that are known to be reliant upon ash for their habitat. With this in mind, if we consider the loss of ash trees on a global scale the consequences are overwhelmingly bleak. I’ve become fascinated with the EAB story and somehow it will have an underlying presence throughout this project. Whilst Bug Cinema is a celebration of forest wildlife, in the context of the EAB there’s always that darker ‘what if’ scenario to contemplate…

Emerald Ash Borer:

The Emerald Ash Borer, Agrilus planipennis Fairmaire, is an invasive wood-boring beetle. Native to Asia, the beetle’s first North American populations were confirmed in the summer of 2002 in southeast Michigan and in Windsor, Ontario. It is believed that the EAB was introduced to the area in the mid-1990s in ash wood used for shipping pallets, packing materials in cargo ships and possibly timber imports. Emerald Ash Borers feed on and eventually kill all native ash trees. It doesn’t take a leap of faith to be mindful that the origins of this invasive, ecological pandemic can likely be traced back to unregulated deforestation in Asia.

an example of the EAB larvae damage to an ash tree

The EAB lays its eggs in bark crevices of ash trees and, once hatched, the larvae chew through the outer bark and then feed on the phloem (inner bark – the pipeline through which food is passed from the leaves to the rest of the tree). More in-depth information about the EAB’s complex biology can be found on the New York Invasive Species (NYIS) website.

multi-state map of EAB detections

 

 

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