trees – Page 3

Tay Meadows Tidbit – Resilience

While walking through the cedar woods at the back of the property last week, I came across this oddly-shapen poplar tree. Being so used to the idea that trees grow vertically, any trunk that crosses that pattern really stands out. What was particularly interesting to me about this tree was the curve in the middle. How would that have happened? It’s almost as though the trunk was made of plasticine and sagged once it was horizontal.

You can’t really see it in this photo, too many trees in the way, but the branches at the top of the tree curve up from the trunk and are growing vertically, suggesting that the tree, despite the big split in its trunk, is still alive. So my first thought was that this happened when it was still shorter, and the stuff to the right of the big curve has grown since. But that doesn’t make sense, either, because the tip should have started growing straight up again at the point where it found itself horizontal, which would have been the low point on the curve in that case.

Looking more closely at the trunk, it would appear that this isn’t the first time this poor tree got broken. There’s the fresh snap, still looking a little raw and coloured, at the far left. Then, just a short distance to the right of it, is a jagged bit of wood sticking out from the line of the trunk. It looks like some years ago the trunk snapped at that point, but not completely. Cause is hard to say, being an old injury. The top part of the tree toppled to the side, but was still affixed enough to keep growing. It did, at that point, turn to start growing straight up, and it probably lasted that way many years, given the thickness of the trunk and how much tree is grown from the point where the trunk makes a right-turn (see image below). This old break might have happened in two stages, a small tear first that caused the initial swooping shape, and the second, larger rip that resulted in an abrupt right-turn as the tip corrected for its new orientation.

Perhaps, eventually, the top part of the tree, growing sideways from the trunk base, grew too heavy to continue to be supported, and the trunk broke a second time. Given the vertical growth of the branches at the top of the tree, this second break didn’t kill it, either. What amazing resilience.

Resilient tree, pre-break — My crude reconstruction of the tree before the most recent break, but after the first (simply rotated the top half of the tree in Photoshop so it'd line up with the base of the trunk).

The most popular of 2009

Yesterday I highlighted what my favourite posts of the last year were, choosing one per month (and leaving out many that were probably just as worthy as a result). As a related idea, last year I also summarized what the most popular posts of the year were, and I thought I’d also do that again this year. WordPress keeps tabs not only on how many visitors your site gets, but also which pages they’re visiting. By far and away the page that gets the most visits is my home page, with the blog stats returning 33,333 hits in the last 365 days, as of this evening. My “About Me” page also gets quite a few. But what about the others? What are people looking for?

Well, most people are looking to find more about milk snakes. Although I don’t typically rank very high on the Google web searches, my photos can often be found on the first handful of pages of results for relevant search terms. I think this is how most people searching for milk snakes, or even just “snake”, arrive here. In a search for “eastern milk snake”, the above photo even makes the first page, and I suppose is different enough to catch people’s interest. A grand total of 7,861 people dropped by to check out the milk snake post.

Compared to the milk snake, all of the rest of my posts have a rather paltry visit count. The next closest, if you can still even call it close, is my grapevine beetle post. The above photo comes up on the first page of image results for “grapevine beetle”, and probably accounts for much of the traffic. There aren’t very many images on that first page that offer a sense of scale, so perhaps that’s why this one is interesting. Over the last year, this post got 2,139 people visiting.

Ranked number three, with just 1,509 hits, is my post on poison ivy. Given just how many pages there are out there about the subject, it’s surprising that it gets even that much regular traffic. It doesn’t come up on the first few pages of Google results.

Coming in fourth is my post on White Pines, the Tree of Great Peace. It collected 1,298 page views over the last year. It’s likewise a commonly discussed subject, so visitors must be coming by way of more detailed searches.

I’m a little surprised that my fifth-ranked post, about house centipedes, isn’t higher on the list considering how creepy most people find them. On the other hand, so many people find them creepy, there’s lots of web content about them. It had 1,292 hits.

Number six is about water bugs – a handful of species of invertebrates that I found in some pond water samples. Although the post mentions a number of species, I suspect many, if not most, of the 1,264 visitors were searching for info on blackfly larvae, the corresponding photo of which, above, comes up on the first page of Google image search results for the subject.

The seventh post, I’m delighted to say, is about a few colourful moths. Yay moths! I would hazard a guess that the particular moth most of the visitors were interested in was the Isabella Tiger Moth, above, which is the adult form of our very familiar Woolly Bear caterpillar. The above photo is the very first image returned for the Google image search “Wooly bear caterpillar moth” (number two if you spell woolly with two L’s). It’s had 1,235 visitors over the last year.

Some 1,185 people have come by to check out my post on flamingos. The post was titled “pink flamingos for the yard” and I’ve noticed a number of search terms on my stats pages indicating people looking for plastic lawn flamingos. These ones probably weren’t what they were looking for; they were captive birds kept by a neighbour down the road from my parents’ old house who bred them and sold them to zoological institutions.

I noticed that as soon as my post on snapping turtle eggs went up last June that it started getting a lot of hits. In just half a year it’s accumulated 1,149 page views. It’s a shame that the eggs I found had been depredated already, but hopefully the post at least offered some useful information.

And rounding out my top ten, the only other one with more than a thousand hits (1,007 total), was my post on giant water bugs. This one got picked up on a web forum – for video game animation or something weird like that – which still brings me periodic hits. The popularity, I think, is partly due to the post’s title, “monster bug”. One of the photos comes up on the second page of Google image results for that term.

It’s interesting to note that only two of these ten posts are actually from 2009: the white pine and the snapping turtle. All the rest are from 2008.

Wrinkles of time

I’ve been wanting for a little while now to repeat a post I did early in the life of this blog. In fact, it was the third post I wrote here (not including the “Hello world!” introductory post), two years ago less a week, on January 13, 2008. It concerned a subject that my mom had recently (at the time) discovered in a library book she was reading, though I seem to have neglected the name of the book.

We all know that you can count the rings of a tree’s trunk, once it’s been felled, to figure out the age it was when it died. You can also do the same thing for large branches by taking a cross-section. But did you know you can also observe the passage of years on the twigs at the end of the tree’s branches?

As a twig grows, its extension of length follows the same stop-and-start pattern as the rings in the tree’s trunk (which represent the laying down of new wood each year), since obviously they don’t continue growing in the winter months. At the end of the fall, before the twigs stop growing for the year, trees such as this maple develop flower buds at their tips that will turn into next year’s flowers come spring.

Where they set their buds (regardless of whether or not the twig develops side branches) the bark of the twig “wrinkles”. You can’t see it at the point of the flower buds, but you can easily detect it for previous years. Look closely at the two photos above. See how there’s spots along the twig, about the same length as the twig is wide, where there appear to be a whole bunch of ridged rings clustered together? You can also see it at the base of the side branches on the top photo. That’s where the buds formed that year. Once the flower buds have finished and the tree has released its seeds, the twig continues growing (at least, I believe this is how it works; I poked about online to confirm, but couldn’t find anything that mentioned it. It would be hard for the twig to grow while bearing flowers at its tip, though).

The rings persist many years. This is from much farther back on the branch; you can compare the thickness of it to the twig that’s coming off the side. The rings are still present, but you can see the ridges of the bark just starting to cross through them.

Because they’re a long-lasting physical feature, you can count backwards to examine the annual growth of each twig and branch. Here’s a sample, above. On this small twig I found four sets of rings, set at various intervals along its length. Each ring represents the start of a new year’s growth, with the portion of twig between each ring having grown in that particular year. So if we consider the small flower buds at the end of the tip as 2010’s new growth, then the section of twig just below the flower bud was what the tree produced during 2009, back as far as the first set of rings. The bit of twig between the first and second set of rings was the growth from 2008, and so on.

I only show as far back as the rings formed from the flowers of 2006, but I could trace back a few more years along the branch behind it (it just wouldn’t’ve shown up well in the photo). It’s interesting to note that the tree doesn’t grow the same amount of twig every year. The length it grows depends a lot on weather conditions such as temperature, and the amount of sunlight and rainfall. In optimal conditions, the tree will produce more twig growth, and in poorer years the growth will be shorter. It can also vary from twig to twig. It’s less pronounced on this twig than it was on the sample twig I used two years ago. (Also note how green the background was two years ago!)

Incidentally, data from the University of Waterloo about an hour and a half west of Toronto indicates that rainfall was about average in 2009, above average in 2008 and 2006, and below average in 2007. Doesn’t really help explain the growth pattern, does it?

Have a look at your own trees next time you’re walking by. Try comparing them to trees in other areas or other habitat types. See any patterns? Yes? What do they suggest? No? Well, it’s still neat to observe the annual growth spurts, anyway. :)

Request for ID – Fungus or egg mass?

I have great faith in the power of the nature blogging community to help others with identifications for mystery organisms and objects. Sometimes there are things you come across that you just can’t seem to find the right combination of search terms to produce a result and an ID on the web. You all came through on the comfrey I posted back in the summer. Now I’m asking for your help again; admittedly, this challenge is probably a little more difficult than the wildflower.

I found this stuff in our cedar woods at the back of the property. The woods border on a bog/poor-fen, and are themselves rather wet. It’s nearly uniformly cedar, but there seem to be one or two tall poplars in the middle. Also mixed in are a few small snags that looked like they were maybe once upon a time also poplars, but were in any case not cedars. I found half a dozen of these small snags, and every single one of them had these brown cakey masses on the sides of the main trunk. I didn’t spot any small trees with this bark pattern that were still alive.

They ranged in size from a few inches long to as much as seven or eight. Some were a rich brown, while others were nearly the same colour as the bark. All of them were covered, to some degree, with algae. And all of them had these tiny holes, about 2-3mm in diameter, clustered mostly around the edges and sparingly across the middle. I tried to peel it up to look underneath or assess its texture, but it was woody and firmly attached.

My hypothesis was that these were egg masses of some sort of insect. I also considered fungal growths, but then what are the holes? I’m reminded of a post I did in the first couple of weeks of writing this blog, about the bracket fungus Cerrena unicolor, which has a symbiotic relationship with a horntail wasp, whose larvae feed on the fungus’ mycelium in exchange for carrying the fungus’ spores to its next host. The fungus then also uses pheromones to attract an ichneumon wasp that parasitizes the horntail larvae, presumably helping keep the horntails from going crazy and decimating the fungus’ root system. Maybe it is a fungus and there was something like that going on here?

Any thoughts?

Speaking of trees and stuff, the January edition of Festival of the Trees is up at Xenogere. Jason takes us on a walk through the Celebration Tree Grove in Dallas, Texas. I encourage you to head over and join him.

Destructive beauty

I hope everyone had an enjoyable and relaxing holiday! It can be such a busy time of year for many people, sometimes it takes a conscious effort to slow down and sit back for a bit. I had a nice visit with my family, who are so spread out over eastern Ontario these days (no one is closer than an hour to anyone else, and the farthest distance between two of us is four hours) that we don’t have many occasions where we’re all able to get together. Needless to say, the break in the usual routine proved a slight distraction from online activities, and I’m just getting back into the post-holiday swing.

This afternoon was beautiful and sunny, albeit a bit on the cold side. I bundled up and took Raven out to the 100-acre woods for her daily exercise. We got a couple of inches of snow yesterday night, and the landscape was freshly powdered. I admired it all, through the narrow gap between my toque and scarf, but didn’t take many photos. I already have lots of lovely winter landscape images. There’s only so many I can actually put to use. You’d all get quite tired of seeing snowy scenes if I photographed and posted every spot I admired.

Christmas night and into Boxing Day we got a fair accumulation of freezing rain. In most open areas, where the sun can reach and shine on the branches, the ice had melted off. However, in the confines of the forest where direct sunlight is sparse and fleeting, much of it still remains on the trees, a glittering coat about 1/2 cm (~1/5 inch) thick. We haven’t had any above-freezing temperatures that would melt it in the absence of direct sun, and so it persists. Where they catch the sun as it filters through the branches, the ice-coated trees can be quite beautiful, glittering like crystal. I wish that the camera could capture the scene as well as the eye can perceive it.

Ice can be incredibly destructive, too. Pine trees seem to suffer the heaviest casualties. Of the pines I passed today, very few were unscathed, and most had at least one limb lying on the snow at their foot. The pine out in front of our house has lost two branches. We had some wicked winds yesterday night, and they may have helped to bring down some branches that might otherwise have escaped damage simply through the weight of the ice itself.

The problem for pines seems to be that their long needles all sit slightly separated, so that when the ice freezes on them they can hold a lot more of it than an equivalent limb on a spruce (short needles), cedar (few spaces), or other evergreen might. Generally speaking, evergreens have developed very strong limbs that can support more weight than the average deciduous tree might be able to, because they need to be able to hold the heavy snow and ice that accumulates on their needles. Deciduous trees have comparatively weak limbs – they don’t need stronger ones because they drop their leaves in the winter, instead, and ice and snow buildup is relatively minimal.

Underneath the big maples in our fields the snow is scattered with shards of ice, crystals that have dropped from the tree’s overhanging limbs as the sun has warmed and melted it. It crunches underneath my snowshoes as I walk through. The maples sit out in the open, exposed. They lost a few twigs and smaller branches with the winds blowing the weight of the ice-covered limbs about, but compared to the pines, it was simply a light pruning. You’d be hard-pressed to even detect where the branches fell off from.

Enough ice collected on the dried grass stems in the fields to lay them flat, and blowing snow from last night has all but covered them. Strange shadows, grass blades carved in relief from the surface of the sheet of white. A few scattered stems still project from the soft surface, and these, too, will soon be hidden by the next storm, or perhaps the one after.

This area was part of the Ice Storm of 1998. The nearby town of Smiths Falls actually makes the Wikipedia page on the event as it was one of a number that declared a state of emergency. Perth and vicinity received in the neighbourhood of 60-80mm of freezing rain – assuming it all froze solid, that would be 6-8 cm (2.3 to 3.1 inches) of ice coating everything. Millions of trees through the affected region were damaged or destroyed. Aside from the obvious aesthetic effects, the storm also crippled the maple syrup and orchard industries, who depend on healthy trees for their crops. I bet woodpeckers were one of the few groups to substantially benefit from the storm, as the sudden preponderance of dead trees and snags would provide a bounty of nesting and foraging sites. Although there are very few signs of the storm remaining, or at least ones that can clearly be attributed to that particular event, I do sometimes wonder about bowed trees like these, and what weight might have caused them to bend so.