Yesterday I wrote in my post that I had measured the Himalayan cedar tree, Cedrus deodara, in our yard to see how tall it was. I guess I was a little surprised that nobody asked me how I accomplished that. For years, I'd been thinking and maybe even saying that the H. cedar was probably about 75 feet tall. My measuring method put it at about 72 feet. Not bad, eh? By the way, a book I have called Taylor's Guide to Trees says that under cultivation this kind of cedar grows to about 80 feet in height. (It grows a lot taller in the wilds of the Himalayan mountains.)
I didn't figure this out all by myself, of course. I found the measuring solution on... wait for it... the Internet! Here's how you can measure the height of a tree, or anything else, using your digital camera. You need to find a stick, pole, or piece of pipe, for example, that you can measure to determine its length. You could even ask a person whose height you know to stand up against the tree trunk.
By the way, the view of the tree that you see in the photo on the right is one that we've never had until now. It was blocked by the blue Colorado spruce tree that we just had cut down. You can see the spruce stump in the photo, and see how close together the two trees were growing.
By the way, the view of the tree that you see in the photo on the right is one that we've never had until now. It was blocked by the blue Colorado spruce tree that we just had cut down. You can see the spruce stump in the photo, and see how close together the two trees were growing.
Once you have that pole or person up standing up against the trunk of the tree, you move back and take a photo in which the whole tree is visible. In the two pictures above, you can see the pole — a broomstick — that I used. It might be hard to see in the first picture, which shows the whole tree, but if you click or tap on it to enlarge the image, the stick will come into view. Just to make sure, I did an enlargement for you, above.
Now what you have to do is measure the length of the pole on the photo of the whole tree, and measure the height of the tree on the photo. I knew that the broomstick I was using actually measured 1.3 meters in length. I printed the photo, thinking it would be easier to take measurements on a paper image than on a computer screen. It turned out that the tree was about 17 times taller than the broomstick. So do the math: 1.3 x 17 = 22.1. That's the approximate height of the tree in meters. In Google, search for "22 meters in feet" and you learn that it's 72 feet. Neat.
In scouting they have a different way of figuring out the height of a tree. https://scoutmastercg.com/how-scouts-measure-height/ You might not have a camera....Within the last week I was fascinated by this way of photographing one of the tallest trees in the world, though the article is not that recent.
ReplyDeletehttps://www.dailymail.co.uk/news/article-2568138/Extraordinary-length-shot-President-one-largest-trees-Earth.html. You are lucky to have this wonderful cedar.
That sequoia is amazing. We saw a lot of sequoias when we lived in California, but not that one.
DeleteI think the Daily Mail, a British newspaper, got confused by the fact that Sequoia National Park is on the western side of the Sierra Nevada mountains. It's not in the state of Nevada, but in California.
DeleteIn the park-like yard we had in Paris before it was expropriated by the State, grew a tree that my father told me was a Wellingtonia. That was the name that John Lindley gave to the Sequoia! And a Sequoia it was!
DeleteI just assumed you had climbed up to the top with a measuring tape!
ReplyDeleteI would have liked to have seen a video of that! Interesting that you had a sequoia in your yard. Net days the tallest one in France is 189'in Ribeauvillé. Maybe the cedar will thrive without the competition from the spruce!
DeleteAmazing: there are about two thousand sequoias known to be growing in the région Centre-Val de Loire in France, including one not more than a mile from our house. Now I have to go find and photograph it.
DeleteThat would be fun to see Ken!
DeleteAccording to this web site featuring an inventory of all the giant sequoias growing in the France, there are 18 of them in Blois, 6 in Montrichard, 5 in Noyers-sur-Cher, 18 in Romorantin-Lanthenay, and others in Thésée, Selles-sur-Cher, St-Gervais-la-Forét — all towns that are within easy driving distance of Saint-Aignan.
DeleteTrying again to post that link.
DeleteVery clever!
ReplyDeleteI figured you had triangulated it, if you know the distance from the base of the tree on level ground, and the number of degrees from the horizon to the top of the tree, geometry solves the rest. I remember doing that in school - about 50 years ago. Today, I would ask Charlie in my office, he would give me the answer in about 10 seconds and then say "well everyone knows how to do that!"
ReplyDeleteI thought about asking you how you measured the tree. Now I know.
ReplyDeleteVery clever, indeed! Years ago I read an article about measuring tall things, in this case to the top of a church steeple. You place a pipe, broom, etc. in a vertical position next to the church and when the shadow of the pipe is the same length as the height of the pipe, you can then measure the length of the shadow of the church. It will be the same as the height to the top of the steeple. It helps if you do this on a sunny day. ;)
ReplyDeleteHahaha, to be honest, I did wonder how you'd measured that, I just didn't have time to type a post/to ask yesterday. Thanks for sharing that - must try it with the tree in our garden (we only have one, but that's enough in a small garden).
ReplyDeleteKen! I assumed being so technically able that you used the same gadget my engineer friend, Brian has. He just points the small, cellphone sized gadget at the top and then at the bottom. Alakazam! The distance is printed out on the screen. It is the same gadget used by surveyers and assessors to measure land and houses. The other assumption was that you used the triangulation/geometry formula! Anyway, your result will encourage me to now measure the height of a tree on another piece of property that I need to have cut down! Merci!
ReplyDeleteYou know what they say... never assume.
ReplyDeleteHa! I thought about asking, then figured you'd either known how or looked it up in some reference. Pretty good earlier guessing on your part.
ReplyDelete