Owen Clarkin: Tree Educator, Activist, Treebadour

“One of my personal goals is to renew legacy trees by intentionally planting young specimens from the spectrum of our indigenous species, before the older ones are all lost to us.” Owen Clarkin is a tree-loving activist who shares his knowledge of trees and the threats to their health, and his passion for preserving indigenous forests with tree planting.  

Photos:  Faris Ahmed

Q.1. When did you start caring about trees? Was there a specific time or event in your life that spurred your interest in trees?

Very early. I have always been keenly interested in nature and especially trees for as long as I can remember. The interest is probably largely innate, but three factors likely solidified it:

a. Early memories (early 1980s) of witnessing many very large American elms (Ulmus americana) either dying or recently dead from Dutch Elm Disease in the mostly agricultural landscape of my community. I found it hard to believe such a disaster could be brought on by an invasive fungus, and I wanted to “save” the old elms which were still alive.

b. Luckily, my household (like many at the time) had a copy of R.C. Hosie's book Native Trees of Canada (7th edition). As a youngster I studied that book carefully, and quickly learned basic facts and identification traits for the native trees of our region.

c. Almost 10 years later, at maybe the age of 12, I walked to a distant woodlot to examine a tall-looking conifer which I had been watching for years. Getting close, I recognized it as being a very large (~110' tall) white spruce (Picea glauca). Then I noticed that the tree was surrounded by a grove of shorter though still quite large and stout conifers, of a type that I had never seen before. These other conifers were strikingly beautiful, and I was overcome with a sense of being “in the past.” Having read about our native trees for years, it shortly dawned upon me that I was in an ancient grove of hemlock (Tsuga canadensis). The landscape in this particular spot of eastern Ontario is prime agricultural land not near a waterway, and by some historical accident this small woodlot contained large hemlock trees as a dominant species: a direct glimpse into the recent (<200 years) past of the landscape. Given how totally different the present landscape generally is with hemlock often being locally extirpated from recent-growth woodlots, and yet a dominant tree in this small, benignly-neglected woodlot surrounded by corn and soybean fields, this experience undoubtedly strengthened my interest in preserving our indigenous forests.

 Q.2. Where does your knowledge about trees come from?

Up until recently, my knowledge of trees has come from observing trees that I encounter, and using a variety of books and websites to make sense of what I notice; i.e. I am self-taught. Over time I've found a group of books that experience has proven to be very good, while some others were found to be not so good.

 With the emergence of social media, I've of late greatly increased my knowledge about the trees of distant places as well by participating in forums. I administer several Facebook groups on Tree and Plant Identification, effectively volunteering my spare time to solve other people's identification problems. But, I have also gained much from this. I've learned how to recognize the distinctive features of many remote trees and plants without the expense of having to travel and see them first hand. Social media Plant ID feels a bit like an inexpensive modern-day version of how in the pioneering days of taxonomy Linnaeus had agents all over the world collecting and bringing plant specimens back to him in 18th-century Sweden; fortunately I can see and get to know these plants from the comfort of my living room.

 Q.3. Why do you care about trees?

I have always been deeply interested in trees inherently. In addition to this, over time I have increasingly realized that trees are a primary foundation of the terrestrial biosphere; a living structure. This is often not explicitly appreciated by the public at large, including many naturalists. But one only need consider the vast array of insects which are specialists requiring certain species and genera of trees as food; in this sense, the kinds of trees and other vegetation one finds locally determines much of the resulting insect population. Many birds are also heavily dependent on the types of trees present, and on the arrangement of these trees (e.g. woodlot, fencerow, forest). Same goes for fungi, lichens, etc.

Q.4. With whom do you share your knowledge and passion about trees? How?

Knowledge is shared with everyone interested. At present I don't work on trees for remuneration and so don't need to wait until I've landed “clients” and furthermore I am free to speak my mind on industry practices, etc.

This interest is shared in a large variety of ways:

-in person or telephone conversations, answering e-mails etc. with colleagues and general public
-exploration of new sites with colleagues
-site visits with land-owners, sometimes with thorough inventory of the trees present
-donating seedlings to be planted in the landscape, usually these are “under-represented” tree species
-leading hikes for Nature Clubs
-public lectures
-website with galleries of images and identification tips (under development)

 Q.5. What motivates you to study trees?

Originally it was an innate interest. This remains but has deepened with conscious realization of how the status of particular trees has been and continues to be rapidly changing. The human impact on trees has been immense, from clearing indigenous trees away, to often replacing such departed trees with foreign species or cultivars (e.g. monocultures), to introducing devastating pests such as Dutch Elm Disease and Emerald Ash Borer. One conscious effort has been to undo some of this damage by for example reintroducing seedlings of tree species to areas from which they have likely been extirpated.

Tree conservation is not often considered in an age where the fate of many animal species is looking grim. But conservation problems are not to be underestimated for trees either. Many species/genera are presently suffering from devastating invasive pests, increasing pressure from native herbivores (e.g. mountain pine beetle, white-tailed deer), habitat loss, dubious tree planting practices, climate change (can't just “move” to a new location), and competition from aggressive foreign plant species. Additionally, trees suffer from problems not typical of herbaceous plants: they tend to mature slowly with long generation times, are “mined” in the wild for resources (wood, etc.), and by virtue of being large plants they can individually need considerably more space than other plants to have a viable population size in a local area.

So, a parcel of preserved land adequate in size to conserve a population of smaller plants may for example be inadequate to conserve certain species of trees. The life-habits of many trees are therefore sensitive to our modern age of resource extraction, habitat loss, and general disturbance, with local extirpation being a typical threat. I have studied identification techniques for every species in the hope of being able to recognize population sizes and trends of species communities in the past (via photographs and herbaria specimens), at present, and in the future.

 Q.6. From your perspective, what are the contributions made by trees that make them so important?

The contributions from trees are almost too numerous to grasp, and include:

-habitat (the “vertical” in forests, etc.)
-resources (wood, fruit, medicine) to humans and to other animals, plants and fungi
-landscape definition, especially stately isolated individual trees, majestic forests, etc.
-environmental services: cleaning air/water, retaining water at a watershed level, generating oxygen, holding soil together, hydraulic lift of water from deep in soil toward surface, helping convey water inland from rain nearer coasts via evapotranspiration (e.g. “rivers of air”), slowing down wind near the earth's surface, etc.

 Q.7. What do you see are the main threats to the trees in our region?

The main threat to trees is without a doubt our general indifference to trees and a tendency to take them for granted. There are many technical problems presently associated with trees (invasive pests, habitat loss, climate change, etc.) which may directly lead to problems such as local extirpation or longer term even extinction of some species, but all these problems are likely solvable with our current knowledge and technology if we were to put forward serious efforts to combat them. Very little has been done to date, but an optimist would hope for this to change.

 Q.8. In your opinion, what tree species is the most interesting in eastern Ontario/Western Quebec? Why?

Rock elm (Ulmus thomasii) is in my opinion the definitive eastern Ontario tree. It is probably at least as abundant here as in any other part of its range, but even here it's presently uncommon to rare and little known even by most “tree people.” Rock elm becomes a large tree with valuable wood, relatively large seeds sought-after by wildlife, and a charismatic growth form combining ruggedness with grace. This tree has supported many specialty hardwood industries in Ontario and Michigan from hockey sticks, piano frames, automobile frames, ship frames, etc. Due to the tree's large size, good growth form and toughness of wood, it was even exported as square timber to England when sufficient quantities were still available.

Sadly, this species which helped build North America is now largely obscure and ignored. I and a few other admirers have been trying to raise awareness of this species, and have been giving out seedlings in recent years. Full-sized majestic examples are now rare, but they can be seen for example in the towns of Merrickville and Hartington, Ontario (links below). Scattered medium-sized to fairly large examples dot the landscape of eastern Ontario and western Quebec, with root colonies of smaller sprouts often being found in mature forests.

Link to Merrickville's Tree

Link to Hartington's Tree

 Q.9. What benefits do you get out of spending a lot of time in forests and in green spaces?

The benefits are primarily associated with mental and to a lesser degree physical health. Going into the woods is literally an escape from the problems of the modern world; a place to recharge.

 Q.10. There are so many aspects to trees, at this point, is there anything in particular that you are interested to learn about trees?

I am particularly interested to learn more about:

-the present abundance and distribution of specific trees in the landscape
-methods to effectively combat invasive pests which are to date destroying up to a third of our indigenous tree species and genera
-the evolutionary history and inter-relationships of trees (phylogenetics)

 Q.11. Finally, do you have a favourite tree in Ottawa? If so, what kind of tree is it and where is it located?

Hard to pick one favourite tree, but I managed to do so. I select an old slippery elm (Ulmus rubra) near Mooney's Bay, which is on public land and can be walked up to by anyone. This is a good example of a “legacy tree;” a fine shade tree which was not likely planted by anyone (it was already “there”), and yet continues to exist in the modern built-up landscape where, due to questionable and simplistic planting practices, it is unlikely that it would be planted again should it die of old age. One personal goal is to renew such legacy trees with intentional planting of young specimens from a spectrum of our indigenous species, especially before the older ones are all lost due to old age.

Trees may seem immortal, but generally they live only about two-three times an ordinary human lifespan under good conditions, and the time is approaching when it will be impossible to find individual specimen trees in the landscape dating back to the age before intentional planting by humans was the norm. What we choose to sow today either continues on a presence for our indigenous species in the human environment, or doesn't. Slippery elm is not well-known generally, which is a shame as it makes an excellent shade tree and has economically valuable medicinal bark (google “slippery elm” for evidence).

Link to this slippery elm here and via Facebook:

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