A Walk In The Park

 More and more medical practitioners are prescribing a walk in nature to benefit their patients mentally, physically and spiritually. I just read an article in a recent issue of Canadian Geographic magazine that features a BC doctor doing this, and who was instrumental in the establishment of the PaRx program, which stands for Park Prescription, and encourages people to spend at least a couple of hours a week in nature.

As most readers will know, I have been practicing a walk in the park for several decades. I know it has contributed immensely to my mental, physical and spiritual health.

I don't do as much of it in the heat and humidity of summer compared to my favourite seasons of spring and fall. But I still try and get out as much as possible, and a few days ago I purposely went out to Rondeau, in part to document some of the endangered Red Mulberry (REMU) trees I know of. Naturally occurring populations of REMU are fairly limited in Ontario and Canada, with places like Pelee Island, Point Pelee, Rondeau and the Royal Botanical Gardens being the best places for it.

One of my favourite clumps of REMU at Rondeau is this clump of three stems.

Clearly this photo was not taken on this trip to Rondeau, but it illustrates how much more readily recognizable they are in the autumn. Typically in late October, when most other tree species are in their golden autumn splendour, REMU are still looking fairly green, and even their leaves do not show much sign of deterioration. Late October is the time I target each year to explore different parts of Rondeau in the hopes of encountering a new location. Last October, for example, I came across at least three new individuals along Harrison Trail.

On this visit, during the growing season, I had to look a bit harder, and noted that most of the ones I saw along the closed stretch of Rondeau Road were continuing to be in good condition. One looks for large, almost plate-sized leaves with obvious drip tips which sometimes are quite obviously lobed.

Large leaves with at least one showing a lobe.

Usually there is some evidence of fruit, but with the hot dry weather of this year so far, fruit is much less abundant.

One of the trees that I have seen in the past, is now dead for some unknown reason. However I did come across a new one, with a fair size to it.

There aren't a lot visible from along the roads and trails, but with so much good habitat not visible from these access points, I expect there are quite a few others scattered here and there. The ones occurring the farthest away from the cottage community are likely the best quality ones, since the non-native White Mulberry is relatively common in those developed areas, and it often hybridizes with the endangered REMU and weakening the genetic make-up of the overall population.

While walking on my route, I noted that there were very few plants in flower, not really surprising since forest wildflowers have large finished flowering due to the heavier shade and reduced light levels. I did see a few of this non-native, but not aggressively invasive, species.

Heal-all (Prunella vulgaris)

Much more surprising was to see this large, female Common Snapping Turtle. If it had been in late May, it would be less surprising, since they would be out looking for a place to lay eggs, and the nearby sloughs would still have lots of water in them to aid in their travels. But by mid-July most of the sloughs are quite dry, and the egg-laying season is long over with. I really had no idea why this one was so far from any real wetland, as aside from leaving a wetland to lay eggs, they seldom leave a wetland for any reason, which is why snappers often have a build-up of mossy algae on their shells from being in the water most of the time.

While walking the closed road was quite pleasant overall, and I enjoyed talking to a good variety of bikers and hikers, I was dismayed to see the ongoing deterioration of the American Beech trees. Certainly the excessively high water levels of recent years has caused some stress to this species which prefers a more upland growing site. But most of the deterioration seems to be from the dreaded Beech Leaf Disease (BLD). The first photo above, showing the autumn colours, was taken in 2009, when the forest canopy was quite dense and more or less covered the road. That was several years before BLD had arrived. It is not for certain exactly when it arrived, but probably in about 2016 or so. These next two photos show what a normally densely leaved Am Beech now looks like: a few scattered leaves, and many of them shriveled.

 This is what the leaves would normally look like, clean and green, with developing flowers and/or fruits.

This is what many of the remaining leaves look like now on the majority of the trees: wrinkled, with black or beige areas paralleling the leaf veins.

There are some trees that have actually died, and undoubtedly many more will fall victim to this non-native disease. Given that the American Beech/Sugar Maple is the main forest type at Rondeau, one wonders what the park will look like in a few years. Already there are signs of change, now that the heavy shading canopy is decreasing. There is quite the insurgence of shrubby growth, such as Spicebush. On a perhaps slightly positive note, at least for the short-term, is that less shade tolerant tree species such as Tuliptree may be on the increase. Also in spite of the loss of various ash species due to the Emerald Ash Borer (EAB), there are still some trees producing seed and there are a fair number of new ash seedling showing up in the more open canopy conditions. Whether they survive to be mature and somewhat dominant elements of this forest remains to be seen. Rondeau has been portrayed as being an old growth forest, but with these changes, it may cease to have some of those characteristics.

Certainly this is not the first time some major vector has affected the forest. Things like the Dutch Elm Disease eradicated most of the elm trees several decades ago, and the EAB has played havoc for a couple of decades now. With the prospect of American Beech declining in a major way, things like Basswood, Yellow Birch, Red Oak and Black Cherry will no doubt become more dominant species, along with the various maple species. Until something comes along to affect them.

Changing gears to another type of park and phenomenon, is the park adjacent to where we live. It is a municipal park, and probably about three decades ago, presumably the municipality planted two American Sycamore trees. Sycamores are not a common species in Ontario, but are widespread in small numbers. 

Sycamore in an upland woodlot

 They can tolerate a wide variety of habitat types, and can be found in upland woodlots as well as along rivers, and everything in between. They grow fairly quickly and are excellent as shade trees, and for those reasons are popular with many. The trunks are sturdy and can resist severe weather fairly readily. The internal characteristics of this species does not lend itself to being easily split, so is not often used in the lumber industry or even for firewood.

The trunk and bark have some interesting characteristics. The largest tree in the previous photo is shown as well in this next photo. There doesn't seem to be anything unusual about the bark.

However as you look higher up the trunk, it takes on a different appearance, with pieces of bark missing and the trunk and limbs having a blotchy appearance.

That blotchiness increases higher up in the tree. As mentioned above, the tree can grow fairly quickly, of course from the inside out. The outer bark ceases to grow, but dries a bit, and then can be sloughed off in various sized pieces. Sometimes the sloughing off is fairly gradual, but apparently in hot, dry and windy weather, it is more obvious. And that brings me to the next bit of this post.

This first photo shows the two Sycamores, one behind the other.

 

The lower trunk is showing signs of the bark being sloughed off. It has happened gradually over the years.

The higher one looks, the more obvious the sloughing has occurred to the point where the limbs are mostly whitish. If you look closely near the upper parts of the two left limbs in the next photo, one can see where it is a bit yellowish. This is where some of the bark has recently sloughed off.

Presumably the relatively cool wet spring caused some good growth of the limbs, but the hot, dry and windy weather of the past month or so has permitted a lot of sloughing off of the bark. As a result, there is a lot of it scattered on the down-wind side of the trees.

Some folks recommend that the pieces of bark can be used for mulch. We have gathered a bit to see how that works.

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