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Posts Tagged ‘Quartz Inclusion’

Actually it was Christmas eve day when a trail I haven’t walked in a while called to me. It was a bright, sunny and warm day with temps nearing the mid-40s F. Days like this don’t come often in a New Hampshire December so I hated to waste it. I hadn’t been the only one to think so; the thin snow on the trail showed many footprints.

There were icy spots on the trail but I had my micro spikes on so I stayed upright. It’s a good idea to have them if you hike popular trails because the compacted snow quickly turns to ice.

There is pond here that’s a popular ice skating spot for local children. In fact I skated here as a boy. The town usually plows the snow off it but over the past few winters it has taken the ice longer to thicken up. I don’t think it was plowed at all last winter because it was too warm for good ice. Plow trucks have ended up at the bottom of the pond in the past so they make sure it’s good and firm before plowing it these days. But kids will be kids and you can see where they have shoveled to make a small skating area.

They pay no attention to the signs. Someday they might wish they had, but I hope not. This sign is on a dam and I’ve seen the pond when it had to be drained to work on the dam a few years ago, and I was shocked at how shallow it was. If a pickup truck went in at the deepest point the water would probably reach to the bottom of the windows.

Spidery cracks in the ice showed that it was still quite thin in places.

When a thin layer of ice on a pond gets snowed on quite often the snow is heavy enough to make the ice sink a bit, and this forces water up through holes in the ice. The water turns the snow to slush, which then freezes into the spidery patterns seen here. For years I wondered if someone had thrown a rock and broken a hole in the ice but this comes from below, not above.

Another thing I wondered about for years was what tree produced such zig zaggy twigs. When I finally realized it was witch hazel (Hamamelis virginiana) I felt pretty foolish, because all I would have had to do was look the plant over more carefully and I would have seen its seed pods and cup like bracts, which would have been an immediate give away. The seed pods especially are unmistakable in the winter. Inside each pod are two shiny black seeds that were much loved by certain Native American tribes. They are said to taste like pistachio nuts but I’ve never tried them. Natives also steamed witch hazel branches over hot stones in their sweat lodges to sooth aching muscles and used its Y shaped branches for dowsing. In fact the Mohegan tribe is said to have shown early settlers how to find water using witch hazel branches, and also how to use the plant medicinally. A tea made from witch hazel tightens muscles and stops bleeding and the plant is one of only a handful of medicinal plants still approved as an ingredient in non-prescription drugs by the Food and Drug Administration. It’s amazing that it is still being used medicinally after what is quite probably thousands of years. 

Two things we have lots of here in New Hampshire are trees and stones and you can find plenty of both along this trail. Some look like they were just left here by glaciers.

A vein of quartz in a stone points the way. Quartz can fill an already present crack in a cooling stone as a hot, liquid brine and some of the resulting veins can be very large. In Frankfurt, Germany there is a hydrothermal vein system that is nearly 4 miles long and almost over 200 feet wide. 

This little fern growing in a crack in a boulder never gets any bigger than what is seen here but it comes back every year to try again. It’s very persistent.

When water finds its way into a crack in a stone and freezes, the pressure from the ice can split the stone, and that’s what happened here. What is unusual about this scene is how a tree seed found its way onto the ground at the bottom of the crack and grew there. I’m guessing that the ever growing tree trunk is pushing the crack in the stone open even more each year. I’ve seen boulders as big as trucks split in the same way, cleaved perfectly by ice.

Stones aren’t the only things in the forest that crack; trees also crack. Straight, vertical cracks in tree bark like that shown above are called frost cracks because they happen in frigid weather when bark repeatedly freezes and thaws. Sunlight warms the bark during the day and then at night when the temperature drops quickly the bark cools and shrinks much quicker than the inner wood, and this causes stress and pressure build up. The unequal shrinkage and contraction between wood and bark can cause the bark to split, sometimes violently and as loudly as a rifle shot. It’s a relatively common sound in the woods at night, but it’s always startling. This frost crack is rare because it is in the bark of a white pine, which has thick bark.

Most frost cracks usually appear on thin barked trees and heal relatively quickly. This photo shows a healed frost crack in an oak.

Here is a scar in the bark of an eastern hemlock that I can’t explain. I’ve shown it off and on in blog posts over the years and many readers have had a shot at guessing the cause but none of us has truly been satisfied with their guess. By far the most popular guess is that lightning made the scar, but the lightning strikes that I’ve seen in tree bark have run as straight as a frost crack. They have also run the length of the tree, while this one comes up out of the ground and runs maybe 4 or 5 feet up the tree.

The zig zag crack is quite deep so I think it has been there for a few years. I’ve seen only one other photo of a similar scar and that also came with no explanation.

Sunlight on a hemlock branch warmed my spirits as much as it did the branch.

When a tree dies it often will shed its bark before it falls if it falls naturally, and the serpentine opening that shows in this tree’s bark is the beginning of the process. I see trees all the time that have all their bark lying in a heap at their base.

Sometimes I see trees that have broken off and fallen and their trunks are completely hollow. I often wonder how many of the trees that surround me in the woods are standing with hollow trunks. That isn’t a real comforting thought especially on a windy day, but I think the wound “window” in this tree shows how it happens. The weathered gray heart of the tree died first and the outer bark lived long enough to start healing the wound. If the tree had lived it would have most likely just been another standing hollow tree, but it finally died and I think the channels showing bark beetle damage all around the wound tell the story of how. Bark beetles don’t usually attack healthy trees but if the tree is alive when they move in it is doomed.

Here was a tree scar that wouldn’t ever heal; someone had cut down a hemlock that was about 5 inches through and I wondered who would do such a thing and why. And then I remembered doing the same thing when I was a boy, and I thought about how I didn’t know then and still don’t know why I did it. This seemed like a good time to ponder such things but I wasn’t able to fill in any blanks. It is healthy I think, to occasionally question our actions. I hope whoever did this will one day ask themselves why, just as I did on this day.

The bark had fallen off an old black birch (Betula lenta) and the inner bark was like confetti. Black birch bark looks a lot like cherry bark when young but once they reach about 50 years old the bark begins to split and form scaly plates. These irregular plates start to fall off when the tree is about 80 years old,  so I would say this tree must be at least that old. The beautiful inner bark shown here will eventually become the outer bark and it will begin to fall off when the tree is about 150 years old. Black birches were once heavily harvested for their natural oil of wintergreen so it’s unusual to find such an old example. I gave it a pat on the bark and wished it well.  

I know this very popular trail has been here since the late 1800s but this tree hasn’t been here that long. Still, it took a lot of foot traffic to wear the bark off its roots like this. I always stop to look at roots like this. Some are so smooth they look as if they had been sanded and polished by a cabinetmaker. Many show wood of different colors and are beautiful.

You will find something more in woods than in books. Trees and stones will teach you that which you can never learn from masters. ~St. Bernard

Thanks for stopping in.

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