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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An Insidious New Disease to contend with

 The natural world is having to deal with a relatively new and serious disease. It is known as Beech Leaf Disease (Litylenchus crenatae ssp. mccannii).

Beech Leaf Disease (BLD) was first noted in North America in 2012, in Lake County, Ohio, right across Lake Erie from Chatham-Kent. It has gradually spread through other jurisdictions, and as of late 2019, is now confirmed in New York, Pennsylvania and Connecticut on the US side of the lake. It was only a matter of time before it was also discovered in southwestern Ontario.

There are eight municipalities in Ontario, from Chatham-Kent in the west, to Niagara in the east and up to Toronto, where as of late 2019 BLD had been found. The key characteristics are dark, almost black areas in between the leaf veins.....

 

....in addition some of the leaves may appear partially shrivelled.

I first heard about BLD about a month ago, in late September, from a keen forest specialist: Gerry Waldron. Gerry wrote an invaluable book on Trees of the Carolinian Forest several years ago. To give Gerry his due, he is the only person who has discovered three new tree species for Canada in his career! Gerry wrote to me, advising me to be on the lookout for BLD. Shortly after checking out some of the characteristics to be looking for, I immediately thought the American Beech (AMBE) trees of Rondeau warranted a close look. For the last 3 years, I had noted Rondeau's beech trees exhibiting severe stress, even becoming partly or almost completely defoliated in mid summer. I thought that it was primarily due to the high water levels that Rondeau has been subject to. AMBE is largely an upland species, meaning they like to grow in a spot where there is good drainage. They don't like to have 'wet feet', at least not for long. They can do alright on the higher ridges of the Rondeau sandspit, and there are some decent sized ones there, indicating that they have been able to tolerate the changing water levels for many decades. However the consistent record high water levels of the last three years have caused major stress to many upland loving tree species at Rondeau.

I immediately started checking the AMBE along many of the trails at Rondeau, and over a period of several days, was quite concerned. I checked the north end of Rondeau Road and the south end of Rondeau Road (now the west side of South Point Trail). I checked the Tuliptree Trail, the Gardiner Deer Exclosure, the southeast corner of the east side of the South Point Trail, and the section of Harrison Trail between Gardiner Ave and Bennett Ave, including the Group Campground. I found evidence of BLD on virtually every AMBE tree I checked. In fact of the one hundred or more AMBE trees I was able to see clearly, there was at least some evidence of BLD on every one. There was a very small number of trees where I didn't see any evidence of BLD, but that was only because most of the leaves were either already off the tree, or they were too high up and obscured by the foliage of other nearby species.

It was easy to conclude that BLD is well established in Rondeau, and an unaffected tree would be a rarity. Here are some of the leaves I photographed at various parts of the park, which depict BLD.

South Point Trail (West)

Tuliptree Trail

Rondeau Road north

I contacted several people within the Ontario Ministry of Natural Resources & Forestry about BLD, and got some more detailed background information. A publication dated in the spring of 2020 indicated that there were only two confirmed locations for BLD in Chatham-Kent: Clear Creek Forest Provincial Park, and Sinclair's Bush, about half way between Rondeau and Blenheim. I sent several representative photos to them, and had BLD confirmed. So the abundance of BLD at Rondeau was new information. 

I checked a few other places that I had easy access to, and where AMBE were known, including:

-Clear Creek Forest Prov Park

-a woodland area along the road that crosses Morpeth Creek

-Sinclair's Bush

-McKerrall Woods, a few km northeast of Chatham

-Paxton's Bush, at the north side of Chatham, and

-a privately owned woodlot along the roadside between Ridgetown and Thamesville

I found evidence of BLD at Clear Creek and Sinclair's Bush, not surprisingly, as well as McKerrall Woods and some inconclusive evidence at the private woodlot between Ridgetown and Thamesville.

Clear Creek Forest Prov Park

McKerrall Woods

Sinclair's Bush

 There are lots of other woodlots harbouring AMBE, but it is getting almost too late in the season for satisfactory checking. A Forestry Health Specialist will be visiting some of these woodlots to collect samples of the leaves and twigs. While the symptoms are fairly apparent, forestry specialists want samples to check, to see if the nematodes that transmit the disease are present.

What does this mean for Rondeau and other woodlands where AMBE is an important component of the forest? It is hard to say for certain at this point. Some trees will likely succumb. However according to some of the persons who have been examining BLD and its affects, some trees show some resistance to the worst outcome.

At Rondeau, the American Beech-Sugar Maple forest type covers a major part of the park. There are other species in that forest type, including Basswood, Black Cherry, Tuliptree, Green Ash and various others. But for one of the main components to become potentially a very minor part, does not bode well. One particular concern is for an endangered bird species, the Acadian Flycatcher. It nests almost solely in the outer branches of AMBE.

Acadian Flycatcher nest in AMBE

For anyone familiar with Clear Creek Forest Provincial Park, you might remember that huge American Beech tree along the main trail. It was one of the largest, if not the largest, of its kind in Ontario. But it showed stress about 4 years ago and died and blew down about two years ago. Interestingly, a small AMBE right beside that massive tree was where I found evidence of BLD just a few weeks ago. It makes me wonder if BLD had some influence on the health, and subsequent death, of that huge tree.

This first image shows the huge AMBE tree in late 2011.

This is what the tree looked like in the spring of 2019, shortly after it blew down.

This next photo was taken just a couple of weeks ago, and the small AMBE in the lower left side of the photo is where I found some leaves showing BLD.

 Over the last several decades, trees like American Chestnut, American Elm and most ash species which at one time were dominant elements of southern Ontario forests, have been severely reduced. The American Chestnut is officially an endangered species. Let's hope that the American Beech does not follow that trend.

No doubt there are many more trees in various woodlots yet to be discovered, unfortunately. Please be aware of this unfortunate situation. I fully expect to be on the lookout for this next season!

Death of a Giant Senior Citizen

It is true....one of the giants of Chatham-Kent, indeed of all Ontario, has come crashing down and is now dead.

I'm talking about a tree, an American Beech tree to be precise. The last time I measured it, it was about 95 cm in diameter at the official measuring height of 4.5 feet above the ground. Here it is as of April 2016.

It is located in one of the newest provincial parks in Ontario, Clear Creek Forest Provincial Nature Reserve, at Clearville in southeastern Chatham-Kent. It is one of the least known and visited natural areas of Chatham-Kent. I devoted a blog post about it in my series of Natural Areas of Chatham-Kent a little less than a year ago. You can read that post at this link.

As I was winding down my career with OMNR in 2011, I took some of the colleagues out to a few sites to pass along various aspects of their significance and management. Here is one of my colleagues being impressed by this huge tree......

.....and here is what it looked like this past week. The staff of Rondeau Provincial Park are in charge of administering Clear Creek Forest, and maintenance staff had been here recently to clear the trail from the huge trunk that had fallen across it.

You can see from the first two photos above that there was a lean to the tree, which is typical of many older growth trees as they age. The right hand side of the base of the tree had deteriorated with age, so it was only a matter of time. One of the fierce westerly winds we had over the past couple of months was the deciding moment, and down it came. Although I doubt that anyone was there at the time to verify it, I am quite sure it made quite a bit of sound when it fell! It took another medium-sized beech tree down with it.

 As mentioned, its diameter was almost a metre. According to one source on trees of the Carolinian Zone, where this species is abundant and grows the best, the largest one known a few years ago was 92 cm in diameter. The tree here was several cm in diameter larger, but the other specimen had not been measured for awhile and if it was still alive, may have surpassed this one. Regardless, the one at Clear Creek Forest is/was one of the largest of its kind in Ontario.

This next photo shows how fragile this tree was in its old age. The outer shell looked fairly sound, but the inside at the bottom was quite hollow, again, not unusual for a tree of this age.

 And speaking of age, I did a count of the rings as best as I could although parts of the cut surface were hard to see due to the chainsaw cuts. You can see from this next photo that some of the rings were quite close together, and others were relatively far apart, reflecting the varying ability to grow over the decades. Certainly a lack of moisture at a critical period of seasonal growth would be one limiting factor.

 Close to the centre, it was impossible to count any rings due to deterioration, as you can see in the next photo. However since American Beech is a tree of a closed canopy type forest, typically the growth is very slow in the first few decades of its life. Unless there is a larger over storey tree that dies or falls down providing a significant amount of sunlight to the forest floor allowing young trees like beech and maple to grow vigorously, the growth rings would be so close together it would be difficult to count them. So with that in mind, I estimated that this tree was at least 250 years old, and could very well have been 300 or more years. Large mature trees are known to live up to 400 years.

Now that this tree is dead, it will no longer be providing beech nuts for critters such as the Eastern Grey Squirrel, Blue Jay, various woodpecker species or Wild Turkey.

However its remains will be quite useful for many other creatures over the next few decades until it completely decomposes. In fact it is well known that a dead tree provides life for far more species than a live tree, so all is not lost. Whether it be beetles or other invertebrates, various species of fungi or other creatures, this fallen log will be of enormous benefit to many forms of wildlife. Salamanders will be one of the larger types of wildlife that will eventually call this rotting trunk home.

Blue-spotted Salamander

Red-backed Salamander

While I was checking out Clear Creek Forest, I wandered the trail to see what else there was to see. Obviously this provincial park is about more than just one tree, although the older growth character along the main trail is certainly an important one, and a reminder of what large parts of Chatham-Kent once looked like.

Spring wildflowers are finally appearing. I saw several species, including:

Dutchman's Breeches

Hepatica

Bloodroot

Skunk Cabbage

Silver Maple

Birds were not plentiful on this brief woodland visit, just things like chickadees and robins.

I did spend a bit of time on the north side of the road where a very different character of the provincial park occurs. There were geese and ducks in some of the ponds; swallows and kingfishers were searching for food, and a couple of Yellow-rumped Warblers were busy in their search as well. On occasion one of the swallows would take a break and rest on a branch over the water.

Northern Rough-winged Swallow

A few Ruby-crowned Kinglets were busily foraging along the shrubby edges of the ponds.

May this forest giant 'Rest in Pieces'