Dr. Dean Coble, professor of forest biometrics, and Jason Grogan, research associate, illustrate how to measure the height of a tree using a yardstick.
A perfect TH-cam video! Useful and informative. No 3 minute introductory scene with spinning logos. No going off on tangents about the history of the yardstick. No electric guitar soundtrack that drowns everything out. No begging for the users to "click the subscribe button and the 'like' button as well".
If anyone is wondering what the geometry behind this is, you're basically making an isosceles (two sides the same length) triangle out of the 30" stick, the 30" line from your eye to the bottom of the stick, and the line from your eye to the top of the stick. Lining the stick up with the tree creates a much larger but geometrically similar (same shape) triangle consisting of the tree, the line from your eye to the bottom of the tree, and the line from your eye to the top of the tree. Since the two triangles are similar (same shape), the fact the length of the line from your eye to the bottom of your stick (30") is the same as the length of your stick (30") means the length of the line from your eye to the bottom of the tree (60') must be the same as the height of the tree (60'). As a side note, we can see that when he measures the length of the line from his eye to where he will be holding the bottom of his stick, he holds his arm slightly higher than when he is actually lining up the stick with the tree. The true length of the line from his eyes to the bottom of the stick is therefore likely slightly over 30", since holding it lower will make it farther from his eye. Consequently in the larger similar triangle we would expect the length of line from his eye to the bottom of the tree (60') to be slightly longer than the true height of the tree (56'), which turns out to be the case.
Military method: take any straight object (pen, stick, tent stake, etc.) and hold it vertically at full arm extension as you did in the video. Position the top of your stick level with the top of the tree, and position your thumb level with the bottom. Then rotate your measuring object 90 degrees while still at full arm extension. Position your thumb against the tree and have a buddy pace out to the end of your measuring object. Your hight estimation will be as accurate as the pacer's pace count. If you use the measuring tape, it will be accurate within a couple of percent. This is how pathfinders determine the correct amount of standoff from obstacles for the approach and departure ends of a helicopter landing zone or parachute drop zone. Like this: th-cam.com/video/F6fltSqImFM/w-d-xo.html
@@Drottninggatan2017 the only thing that matters is that the distance from you and the tree, and the distance from your eye and the stick remain constant. You hold your stick vertical to align it with the tree. I personally do this with a pencil or similar sized object. Once you have set your thumb on the pencil so that the tree appears to be the same height as your pencil rotate 90 degrees to translate that distance onto the ground to easily measure it.
Great video! You don’t need a yardstick, you can use any stick. You don’t need a tape either, just heel/toe steps and a knowledge of how big your shoes are. Try it!
He’s got a hard hat on stand with the best posture you can start at the tree and walk backwards until the top of the tree is in line with the brim of the hard hat! The point you can see it is where the tree will land!! 50k plus trees fell in the city and in the country and anywhere else you can imagine. Never use the “stick method lmao.
Stand your yardstick or ruler on the ground pointing straight up. Measure the shadow of the stick. If the shadow is half the height of your stick - the shadow of the tree will be half the height of the tree. You just need to figure the ratio of a known object to the unknown object's height. The ratio will be the same.
About 50 years ago, I showed a similar method to some scouts whilst at camp. We used the stick at arms length similar to you. Held it so the thumb was at the base of the tree and we moved backwards until the top of the stick was at the top of the tree. The next step was to rotate our wrist through 90 degrees and our thumb was still at the base of the tree, then one of the scouts paced the distance until we told him to stop. We stopped him at the end of the stick. He then placed a marker on the ground and we calculated from his pace (all scouts knew what measurement their pace was) how tall the tree was.We did a double check with a measuring tape and the lads were pleased when that their calculations were very close to the final measuring tape distance/height.
This is EXACTLY the type and quality of video I was hoping to find!!! THANK YOU. My 10 yr old daughter and I had the discussion of how to determine tree(or other object) height from any given distance while while walking to school yesterday... and now we know the distance is key and more importantly... we don't need special tools. This is perfect. Well done...
There is another more accurate way too, but you need a sunny day... Say your daughter is 4 and a half feet tall. She stands in the sun and measures the length of her shadow on the ground. Say her shadow is 6 feet long.. Then she measures the length of the shadow the tree casts.. Say this is 36 feet. Then 36 divided by 6 = 6 Then it is 6 times her height [4.5 feet] to give 27. The tree is 27 feet tall... You like that eh!!
You can also use a compass to measure width by taking a bearing across the object (e.g., river, ravine). Then walk at 90-degrees up or down from that point until a bearing to the same aiming point is + or - 45-degrees. The distance walked is the width of the obstacle. Same as the tree, but on its side.
If one tilts their head back when siting the top of the tree, that introduces that 6 foot error. Site the top of the tree past the yardstick only moving your eyes and the estimate will be even closer. Great video, I needed this information!!
Both of the measurements given are estimates. Neither are "precision". The laser just measures the distance and angle faster. The laser is only as accurate as the user and the tilt at his shoulders produces similar error. If the laser is sited from 2 locations, even inches apart, then it's calculation is skewed. Ever notice surveyors don't use hand-held scopes? That's why. Mounted scopes have an engineered swivel that is taken into account in its calculation, which allows it to site multiple locations with minimal accuracy loss.
We used this method as arborists to determine where a tree will land once felled, although we used pace counts, not the measuring tape. Does a very good job at preventing property damage/personal injury, so long as your notch cutting skills are on point!
When we were kids we measured the shadow cast by the yard stick and the shadow cast by the tree and simply plugged it into a fractional equation, e.g. 36"/60" x/120' Other than the fuzzy tip of the shadow, it was pretty accurate. It was also a great way to motivate kids to learn math.
Sir Author Conan Doyle incorporated a similar method in the Sherlock Holmes story, "The Musgrave Ritual" Your method is just simple trigonometry using the 3, 4, 5, triangle. Keep going on this not only to get children interested but more adults need this as well
In 8th grade my math teacher drew a twostory outhouse on the chalkboard with the lower door open. A stickman stood to one side with a line going from him to the top door. This was the "high pot in use". I've never forgotten that in 55 years.
You can do something similar with a speed square by placing the square on a level surface aligned to the base of the tree and then sighting down the 45° angle of the square aligning it to the tree top measure the distance from the tree to the square. This works because a 45° inclines run and rise match.
You can also post the yard stick next to the tree, stand back until the can see the entire tree in view, measure the whole tree with a tape measure in the stand backed view, then the yard stick and then multiply the two together to get the height. For example, say the yard stick is 2 inches in the stand backed view, and the tree is 50 inches total, the tree is then 100 yards high.
My grandpa was a faller and one time he pulled out a length of string with a weight tied to it, like a stone or a quarter with a hole in it. I had to ask him about it and he said they would wrap it up and put it in their pocket out in the woods. God bless the easy start.
Man that is very informative..Its always good to learn things...I generally just go down to the local bar and complain about a tree I have to deal with...and after a while some retired ( loggers never retire) cutter will say let me come over and look at it... never costs more than a bottle of whiskey and drinks around the campfire.... cheap at twice the price..everybody is happy...I share the firewood with them and have all I need...
Instead of aiming at the base of the tree, like you mention about your "line of sight" beginning at 1:29. Keep the top of your right fist (holding the stick) level with your eye. This is what creates a 45 degree angle in your triangle, that is viewing the top of the tree. If the bottom of your stick is not level with your eye, than your distance will be less accurate. And as Jens R mentioned you need from there to add the height of your arm above the ground. If you are felling in a really tight spot, you could take into consideration the distance above the ground where you will place your hinge.
I think you’re on the right track but that would only be perfectly true if his estimate were too low. In this case, his estimate would’ve been the same, because of the distance to the tree, but adding the height of his arm would only increase the estimate, making it more inaccurate. Your geometry sounds correct but I think we’re just dealing with an imperfect, albeit good enough, method of measurement.
I’m in a rush and had to go at 2:00! Thank you for this! Hard to believe a tree is as tall as a yard stick?! I need to go see how small my oak tree is!
I was giggling watch it how simple it is to measure without technology. That was great. Thank you for taking the time making and uploading this life hack. :)
Interestingly, old things become new again. Learned the same height measuring method in the Boy Scouts oh so many years ago. A great teaching method for youth, plus it improves their math skills.
@@AwesomesMan Either watch the video again (or other presentations) or try it out yourself to determine the math. But, then again millennials can't do math in their head the old school way and are always asking for the answers INSTEAD of discovering it out for themselves. Perhaps videos on using maps and compass would really enthrall your mind.
Oh my god i aint never heard of being able to measure a tree height any easy way! 👍🏻👍🏻 I had no idea that roughly measuring a tree height the easy way exists! Thank you for educating me sir
It's basically geometry. If he had looked closer to the ground rather than looking at a slight angle it would have been closer to the 56 feet. It's 2 principles. Similar triangles. 1 being his arm and the bottom and top of yardstick, being equal (because they are the same angles) in proportion to him and the bottom and the tree's top. The other principle, because the first triangle is 30" (his arm length) and 30 inches (The yarstick height) that makes it a 45 degree angle, but more importantly the length of the base and the height of it are the same, so his distance to the tree equal's the height of the tree. Since he was looking slightly down it wasn't exactly a 90 / 45/ 45 degree triangle which explains some of the variance (also could be the tree bends toward him slightly making it appear taller when measuring with the stick. Also he could find out his distance to the top of the tree (if it was straight and he measured from the ground) as every hypotenuse of a 90/45/45 triangle is either the basse or the height (they are the same) times the square root of 2. So if it were 60 feet high from the ground he would need an 84' rope to lasso the tip top.
You must remember to add the height of your arm over the ground from the measured tree height. If we say you held the yardstick 5 feet above the ground, you should add 5 feet to your measurement. For those wondering this method uses the principle that the two short sides of a right sided triangle are equal.
@@G58 : If he would've added five feet to the yardstick measurement,that would've given him a height of 65'. The laser measurement was 56'.He would've been even more off by adding five feet to his yardstick measurement.
Corrections: [A] The two sides of an isosceles triangle are equal. This triangle happens to be both isosceles and right-angle. [B] I think you mean to deduct the height your arm is above ground level. I might be wrong here. Maybe it would be better to crouch or sit to get your sightline for the base at ground level, and therefore the acute angle at your eye is closer to the 45° mark.
Measuring the distance from your eye to the stick and then holding the stick at that height basically makes an equilateral triangle from your eye, your hand and the tip of the stick.
Your explanation is the methodology of the billmore stick. I worked in coastal BC Canada where ground conditions are highly variable and trees up to 90 meters tall have been measured. 60 meter trees were not uncommon. Basic method we use to use was a simple sunto clinometer to measure the angle difference top to bottom in % instead of degrees x horizontal distance in meters. Worked well for variable distances necessary. Lasers were a real innovation for timber cruising in big timber.
My father was a graduate of the Penn State school of Forestry in the 1950’s. I grew up physically running cruise lines, and by using a Biltmore stick to calculate how much board feet of timber was in an area of land…hard work because one had to stay on as straight of course as possible and this meant transversing around swamps, up hills, etc. we also used paint guns to mark which trees were to be harvested….GOOD TIMES 🙂
@@jcook7148 I'm from Minnesota and that guy is called a timber cruiser. I remember when I was a kid walking on trails marked by axe marks on a trees to keep you on the trail or the "cruise line."
Good video using good old trigonometry. Your hand assessment would be closer to your laser measurement by noticing where on the tree your extended "level" arm was pointing at. You would add the distance from that spot to the ground to your tape distance. In your case on level ground it is 4 feet. This works pretty well when you are standing on the upper side of a hill.
Would it have made a difference if you had held your arm parallel to the ground, then added the distance from your arm to the ground to the measured distance to the tree? In other words, did the negative angle you introduced by aiming your arm at the tree base have given you the four foot error?
Learned to do this with an ax handle from a logger friend of mine, we were just measuring roughly how far the tree will fall when we cut it to determine how far the felled tree would land for hazards but it's cool that we can use this same technique to estimate height if we have a tape
Interesting way of doing it. I always just stood next to it at 6 ft tall and eyeballed 6 ft sections all the way up and added one more than I counted. Then stepped off that distance. Usually ended up being slightly shorter than I measured. Prob shouldn’t be felling the tree that close to anything you don’t want damaged anyway and should climb it and take down in sections.
Alternatively, if you go to the top of the tree, and you hold the end of a 100% straight 90 degree strip of measuring tape that begins right at the base of the tree, you can get pretty accurate results that way too and with only a small risk of bodily harm.
What happens if tree is on a slope? Do you need to try to stand on the same counter as the tree? For example, if you stand upslope from a tree, do your thing with yardstick, and measure along (sloped) ground with vinyl tape, will you still get a reasonable estimate?
If I am not mistaken you do not need a yard stick. Any stick, branch, log or object of arms length will work. I think you could also bend your arm to 90 degrees and sight down your upper arm to the tree base and then sight across your finger tips to the tree top. Then measure to the tree by knowing the length of you steps. Less accurate but probably within a few feet with practice.
I was taught to measure the length of my shadow when it was the same as my height, then measure the length of the tree's shadow. Doesn't work without the sun or in a heavily forrested area but it is accurate
You would have to be measuring at exactly the right time of day though. You could also just measure the shadow length of anything you know the exact height of, calculate the difference and apply the same calculation to the tree’s shadow. This can be done anytime there is a shadow present, regardless of its length.
@@peterk8909 so that means you going to stand around all day measuring your shadow until it is exactly 6 feet? That would definitely work, but doesn’t sound very practical.
60ft actual minus 56ft est. = 4ft Shoulder height at which stick bottom mark was being held... maybe 4.5 to 5ft? I suspect for trees around the 45-65ft mark, using the stick method, such slight over-estimate (between 5 to 10%) would commonly happen. Of course the precise geometry is not quite that simple - and it is after all a rough working estimate. But just thought I'd make that observation. Anyhow assessment with a small over-estimate is always better re safe working and property protection eh?
Pretty accurate. Correct me if I'm wrong, but If you look closely, there was a depression angle (which might cause the 4 feet difference) when you measured the base of the tree with the base of the ruler (because of this the angle won't be 45° anymore) since you were looking down from the horizontal line, from that viewport (which based on the data was approx -5.14°: tan-1 (5.5/60) based on average human height). If you look absolute horizontal from the eye's POV, there's no way to see the base of a tree. You can only see the base of the tree if there's an opening angle (elevation or depression method, further you go, the more field view will be covered with that same angle). To use this method more accuaretly, our eyes should be on ground level, looking up to the tip of the tree, and measuring the distance right from the point where our head was. The easiest way is to get a rectangular ruler with a degree of 45°, hold it to your eye's height, follow the hypotenuse until you can see the tip of the tree. Measure the distance to the tree and add the height from the ground to your eyes and you get the most possible accurate measurement done without any tech tools. :)
Also, if you looked at the person when he took the tape measure to the tree, he held it up at least three feet above the ground which almost completely accounts for the 4 foot difference from the laser measurement.
@@heela188 doesnt matter that he held over the ground since we are meassuring along that plane the whole way. The difference in height cant be explained this way :)
Pythagoras's theorem is always useful. This is how the height of the pyramids were determined by the ancient Greeks. They used similar right angled triangles and shadows cast on the ground.
The method shown is "almost" correct. The reference item is the yardstick (or stick or string & plumb-bob, whatever)...NOT your eyeball. You need to subtract your outstreched arm length (30") from the reading on the tape measure. Also, the Mark-1 human eyeball is way more precise than the laser sensor on your contraption. Swaying tree tops, less upper foilage to reflect light, etc can spoil the lasing meter. Any tilt to the tree can spoil the actual measurement.
I disagree about the reference point NOT being his eyeball. The reference point is the hypotenuse/adjacent side 45 deg angle of the "Small triangle". That point is ~30 inches from the right angle (arm L yardstick). That's approximately his eye.
I use to use a speed square on a level bucket. Keep backing up until the angle lines up with the top of the tree then measure the distance to the tree. But that's a good trick!
I learned a similar method in the Boy Scouts 53 years ago at age 12. Site on the base of the tree with straight object (stick will do) and the top the tree, pivot the base of the stick 90 degrees to the tree! Site on end of the stick that was the top of the tree. Have someone mark that point while you are still sighted on the stick. If you were to fell this tree in that direction that is where the tree would land.
I think I can estimate the tree height just by looking at it and come as close as you did. As a member of a remote control airplane club, I often help people get their airplane out of a tree. Sometimes I use a 100 foot parachute chord. If I get the chord over a branch and it just reaches the ground I know it is 50 feet up. I can add more rope as needed if it is over 50 feet. I can usually guess within 5 feet of how high up the target is.
@@iamf6641 Probably because most people are not good at estimating things. And lets be honest, most men don´t even know the difference between 6 and 12". :p
Well....you measure the height of a tree very carefully. That is how I was taught back in the 1970's.... You all take good care out there now you hear.
That’s just more complicated than it needs to be. Keep it simple, just site at a 45 degree angle to the top of the tree, take a step back and the top will land at your toes. ( use a hand held site level with 45 degree mark if You can’t judge it)
Many years ago while I was deployed, we were trying figure out the height of a flagpole. A young civil engineering officer only ‘sort of’ remembered this method, so we relied on other means. But I’ve always held it in the back of my head and though it would be cool to know. Well, now I do.
You're a professor but didn't throw in the basic reason this works the way it does? Come on man. It's simple geometry, you're creating a 45 degree angle from where you're standing with the tree, and the angle is equidistant and therefore the same length as the vertical tree as is along the ground to it. Think of a speed square, you're creating a gigantic invisible one between you and the tree, with your feet at the point of the 45 point
I have something similar that can do that. "Theodolite" (iPhone) takes photos/videos that will stamp the image with GPS location, direction, tilt, azimuth, time and date. I imagine you could even take a measurement of a tree on the other side of a small river. Take one reading, go farther or closer and take another reading, compare the two angles and distance between the two points.
I was worried they wouldn’t wear the appropriate safety gear when performing this dangerous task. I felt great relief to see they indeed were wearing hard hats.
When the yardstick comes out, the hard hats go on. Thanks for keeping it safe, gentlemen.
A perfect TH-cam video! Useful and informative. No 3 minute introductory scene with spinning logos. No going off on tangents about the history of the yardstick. No electric guitar soundtrack that drowns everything out. No begging for the users to "click the subscribe button and the 'like' button as well".
If anyone is wondering what the geometry behind this is, you're basically making an isosceles (two sides the same length) triangle out of the 30" stick, the 30" line from your eye to the bottom of the stick, and the line from your eye to the top of the stick.
Lining the stick up with the tree creates a much larger but geometrically similar (same shape) triangle consisting of the tree, the line from your eye to the bottom of the tree, and the line from your eye to the top of the tree.
Since the two triangles are similar (same shape), the fact the length of the line from your eye to the bottom of your stick (30") is the same as the length of your stick (30") means the length of the line from your eye to the bottom of the tree (60') must be the same as the height of the tree (60').
As a side note, we can see that when he measures the length of the line from his eye to where he will be holding the bottom of his stick, he holds his arm slightly higher than when he is actually lining up the stick with the tree. The true length of the line from his eyes to the bottom of the stick is therefore likely slightly over 30", since holding it lower will make it farther from his eye. Consequently in the larger similar triangle we would expect the length of line from his eye to the bottom of the tree (60') to be slightly longer than the true height of the tree (56'), which turns out to be the case.
Prefect explanation, I figured out what he was doing when he measured his arm, and started holding the stick up.
Thank you 👍
Thanks for the explanation. I know the theory behind this, but for the love of god couldn't figure it out.
Would your measurement be more accurate if you brought your eye closer to the ground to line up the yardstick?
Thanks 👍
Super helpful and interesting geometric exercise. Also fun to tease you about wearing a helmet for this dangerous task!
Pretty nifty. I always just cut em down to see how tall they were
Bahaha
Same, hate it when it is tall enough and i have to put it back
Don't cut it down, that's deforestation.
@@Waseemmmm stop commenting please
@@BrianHay7 Weirdo.
Military method: take any straight object (pen, stick, tent stake, etc.) and hold it vertically at full arm extension as you did in the video. Position the top of your stick level with the top of the tree, and position your thumb level with the bottom. Then rotate your measuring object 90 degrees while still at full arm extension. Position your thumb against the tree and have a buddy pace out to the end of your measuring object. Your hight estimation will be as accurate as the pacer's pace count. If you use the measuring tape, it will be accurate within a couple of percent.
This is how pathfinders determine the correct amount of standoff from obstacles for the approach and departure ends of a helicopter landing zone or parachute drop zone.
Like this: th-cam.com/video/F6fltSqImFM/w-d-xo.html
Does it matter if the ground is level and if you hold the stick vertically or not?
@@Drottninggatan2017 the only thing that matters is that the distance from you and the tree, and the distance from your eye and the stick remain constant. You hold your stick vertical to align it with the tree. I personally do this with a pencil or similar sized object.
Once you have set your thumb on the pencil so that the tree appears to be the same height as your pencil rotate 90 degrees to translate that distance onto the ground to easily measure it.
Learned that same way for measuring pole heights with the local telephone company! Thanks!
That is the most confusing shit I've read this week
Wha, so you rotate the stick so it’s parallel to ground and your thumb against the tree.??
Great video! You don’t need a yardstick, you can use any stick. You don’t need a tape either, just heel/toe steps and a knowledge of how big your shoes are. Try it!
Good point!
You don't need shoes, just know how big your feet are.
You don't need a real tree, you can just imagine one. Just keep in mind that i² = -1, when holding your imaginary yardstick at a right angle.
He’s like: lets wear helmets in case the clouds comes down.
😂😂
I was looking fr u
That's to stop the alians from harvesting his thoughts dummy
Or aliens
Seems strange at first until you realise OSHA will slam you with a big ass fine if you're caught not wearing your hardhat while on the job site.
For city trees, keep in mind that a standard telephone pole is 35 feet tall. Sometimes you can measure a tree against one.
Thanks great tip 4sure!
Any electrical/phone pole will be in the ground according to this calculation.
2ft + 10% height of the pole.
So a 40 ft. pole would be 6ft under.
@@lalarobert 🤣🤣🤣🤳🙏
He’s got a hard hat on stand with the best posture you can start at the tree and walk backwards until the top of the tree is in line with the brim of the hard hat! The point you can see it is where the tree will land!!
50k plus trees fell in the city and in the country and anywhere else you can imagine. Never use the “stick method lmao.
Nah that’s too easy, I’m whipping out the protractor
Stand your yardstick or ruler on the ground pointing straight up. Measure the shadow of the stick. If the shadow is half the height of your stick - the shadow of the tree will be half the height of the tree. You just need to figure the ratio of a known object to the unknown object's height. The ratio will be the same.
About 50 years ago, I showed a similar method to some scouts whilst at camp. We used the stick at arms length similar to you. Held it so the thumb was at the base of the tree and we moved backwards until the top of the stick was at the top of the tree. The next step was to rotate our wrist through 90 degrees and our thumb was still at the base of the tree, then one of the scouts paced the distance until we told him to stop. We stopped him at the end of the stick. He then placed a marker on the ground and we calculated from his pace (all scouts knew what measurement their pace was) how tall the tree was.We did a double check with a measuring tape and the lads were pleased when that their calculations were very close to the final measuring tape distance/height.
Thank you for showing us how to do this with very simple equipment! It's amazing!
This is EXACTLY the type and quality of video I was hoping to find!!! THANK YOU. My 10 yr old daughter and I had the discussion of how to determine tree(or other object) height from any given distance while while walking to school yesterday... and now we know the distance is key and more importantly... we don't need special tools. This is perfect. Well done...
There is another more accurate way too, but you need a sunny day... Say your daughter is 4 and a half feet tall. She stands in the sun and measures the length of her shadow on the ground. Say her shadow is 6 feet long.. Then she measures the length of the shadow the tree casts.. Say this is 36 feet. Then 36 divided by 6 = 6 Then it is 6 times her height [4.5 feet] to give 27. The tree is 27 feet tall... You like that eh!!
You can also use a compass to measure width by taking a bearing across the object (e.g., river, ravine). Then walk at 90-degrees up or down from that point until a bearing to the same aiming point is + or - 45-degrees. The distance walked is the width of the obstacle. Same as the tree, but on its side.
Good dad award
@@rrcaniglia That is really clever!! Thank you for that!!
That's pretty advanced thinking for a 10 year old. Most are just wanting to climb the tree let alone wonder how high they're actually climbing haha
Excellent presentation and beautifully simple principle. Thanks for taking the time 👍
Outstanding demonstration!
This video is simply very illustrative. Thank you
If one tilts their head back when siting the top of the tree, that introduces that 6 foot error. Site the top of the tree past the yardstick only moving your eyes and the estimate will be even closer. Great video, I needed this information!!
4 foot
@@JerichoRally feet
@@m74796 pics?
4' error?
Both of the measurements given are estimates. Neither are "precision". The laser just measures the distance and angle faster.
The laser is only as accurate as the user and the tilt at his shoulders produces similar error. If the laser is sited from 2 locations, even inches apart, then it's calculation is skewed. Ever notice surveyors don't use hand-held scopes? That's why.
Mounted scopes have an engineered swivel that is taken into account in its calculation, which allows it to site multiple locations with minimal accuracy loss.
We used this method as arborists to determine where a tree will land once felled, although we used pace counts, not the measuring tape. Does a very good job at preventing property damage/personal injury, so long as your notch cutting skills are on point!
why did you feel the need to say you are an abortist?
@@Mr850man why did you feel the need to ask him why he felt the need to say he is an arborist?
@@Mr850man to give context to the real world used of this knowledge?
@@ryanvess6162 Ohh arborist! I read it wrong sir
My cutting skills are pretty rusty I ain't gonna lie but my cunnilingus and donkey punch right hand are a sight to behold!!!
This is why I love TH-cam. very informative video, I will archive this in my brain until the day, who knows when, I can use it. Thank you.
Every day is a day for learning. Thank you very much!
awesome, very useful for quickly estimating tree heights
When we were kids we measured the shadow cast by the yard stick and the shadow cast by the tree and simply plugged it into a fractional equation, e.g. 36"/60" x/120' Other than the fuzzy tip of the shadow, it was pretty accurate. It was also a great way to motivate kids to learn math.
Probably while y'alls was smokin da herb right breh?
@@charlesdarwin7253 Not likely. Just a better school that's all.
What if it was cloudy :)
Sir Author Conan Doyle incorporated a similar method in the Sherlock Holmes story, "The Musgrave Ritual" Your method is just simple trigonometry using the 3, 4, 5, triangle. Keep going on this not only to get children interested but more adults need this as well
@@isailwind3471 This method in the video doesn't depend on the weather.
Simple yet useful, Thales is awesome
In 8th grade my math teacher drew a twostory outhouse on the chalkboard with the lower door open. A stickman stood to one side with a line going from him to the top door. This was the "high pot in use". I've never forgotten that in 55 years.
You can do something similar with a speed square by placing the square on a level surface aligned to the base of the tree and then sighting down the 45° angle of the square aligning it to the tree top measure the distance from the tree to the square. This works because a 45° inclines run and rise match.
that's terrific to know if the tree will hit the house ,thanks
The best video on the subject, thanks!!
Cool! This is a really handy technique.
You can also post the yard stick next to the tree, stand back until the can see the entire tree in view, measure the whole tree with a tape measure in the stand backed view, then the yard stick and then multiply the two together to get the height.
For example, say the yard stick is 2 inches in the stand backed view, and the tree is 50 inches total, the tree is then 100 yards high.
😂
My grandpa was a faller and one time he pulled out a length of string with a weight tied to it, like a stone or a quarter with a hole in it. I had to ask him about it and he said they would wrap it up and put it in their pocket out in the woods. God bless the easy start.
That's pretty darn cool. Thanks.
Man that is very informative..Its always good to learn things...I generally just go down to the local bar and complain about a tree I have to deal with...and after a while some retired ( loggers never retire) cutter will say let me come over and look at it... never costs more than a bottle of whiskey and drinks around the campfire.... cheap at twice the price..everybody is happy...I share the firewood with them and have all I need...
Brilliant!
Probably works for many issues needing addressed.
That gives me an idea for a medical procedure I've been putting off.!
Thanks!
Cringe
Instead of aiming at the base of the tree, like you mention about your "line of sight" beginning at 1:29. Keep the top of your right fist (holding the stick) level with your eye. This is what creates a 45 degree angle in your triangle, that is viewing the top of the tree. If the bottom of your stick is not level with your eye, than your distance will be less accurate. And as Jens R mentioned you need from there to add the height of your arm above the ground. If you are felling in a really tight spot, you could take into consideration the distance above the ground where you will place your hinge.
I think you’re on the right track but that would only be perfectly true if his estimate were too low. In this case, his estimate would’ve been the same, because of the distance to the tree, but adding the height of his arm would only increase the estimate, making it more inaccurate. Your geometry sounds correct but I think we’re just dealing with an imperfect, albeit good enough, method of measurement.
@@beboppalooka9897 What if he subtracted the heigth?
I’m in a rush and had to go at 2:00! Thank you for this! Hard to believe a tree is as tall as a yard stick?! I need to go see how small my oak tree is!
Actually the yard stick is bigge. It Is an otpical solution that the tree loks bigger
lmao
You got enough from the video and understand the concept well enough to work for the government or Google, heck they’ll probably make ya a manager.
I was giggling watch it how simple it is to measure without technology. That was great. Thank you for taking the time making and uploading this life hack. :)
That's a neat tool for measuring height. Thanks that should come in handy.
Interestingly, old things become new again. Learned the same height measuring method in the Boy Scouts oh so many years ago. A great teaching method for youth, plus it improves their math skills.
Yes! I was taught that in the Boy Scouts, too! I still can't do it, though.
Where is the math in this technique?
@@AwesomesMan Either watch the video again (or other presentations) or try it out yourself to determine the math. But, then again millennials can't do math in their head the old school way and are always asking for the answers INSTEAD of discovering it out for themselves. Perhaps videos on using maps and compass would really enthrall your mind.
Reading a tape measure isn’t math.
@@swingbelly You clearly dosent know what math is.
Oh my god i aint never heard of being able to measure a tree height any easy way! 👍🏻👍🏻 I had no idea that roughly measuring a tree height the easy way exists! Thank you for educating me sir
It's basically geometry. If he had looked closer to the ground rather than looking at a slight angle it would have been closer to the 56 feet.
It's 2 principles. Similar triangles. 1 being his arm and the bottom and top of yardstick, being equal (because they are the same angles) in proportion to him and the bottom and the tree's top.
The other principle, because the first triangle is 30" (his arm length) and 30 inches (The yarstick height) that makes it a 45 degree angle, but more importantly the length of the base and the height of it are the same, so his distance to the tree equal's the height of the tree.
Since he was looking slightly down it wasn't exactly a 90 / 45/ 45 degree triangle which explains some of the variance (also could be the tree bends toward him slightly making it appear taller when measuring with the stick.
Also he could find out his distance to the top of the tree (if it was straight and he measured from the ground) as every hypotenuse of a 90/45/45 triangle is either the basse or the height (they are the same) times the square root of 2.
So if it were 60 feet high from the ground he would need an 84' rope to lasso the tip top.
Incredibly useful knowledge
Awesome!! Thank You for sharing your knowledge. I learned something new.
You must remember to add the height of your arm over the ground from the measured tree height. If we say you held the yardstick 5 feet above the ground, you should add 5 feet to your measurement. For those wondering this method uses the principle that the two short sides of a right sided triangle are equal.
well. you may be trying to be more accurate than this method allows. But point taken.
Hence the 4ft difference between the two readings perhaps?
@@G58 : If he would've added five feet to the yardstick measurement,that would've given him a height of 65'.
The laser measurement was 56'.He would've been even more off by adding five feet to his yardstick measurement.
Corrections:
[A] The two sides of an isosceles triangle are equal. This triangle happens to be both isosceles and right-angle.
[B] I think you mean to deduct the height your arm is above ground level. I might be wrong here. Maybe it would be better to crouch or sit to get your sightline for the base at ground level, and therefore the acute angle at your eye is closer to the 45° mark.
I was wondering about that. Different height people will get different results.
Thanks, for this video. Could you explain why you use arms length in inches to calculate?
Measuring the distance from your eye to the stick and then holding the stick at that height basically makes an equilateral triangle from your eye, your hand and the tip of the stick.
Your explanation is the methodology of the billmore stick. I worked in coastal BC Canada where ground conditions are highly variable and trees up to 90 meters tall have been measured. 60 meter trees were not uncommon. Basic method we use to use was a simple sunto clinometer to measure the angle difference top to bottom in % instead of degrees x horizontal distance in meters. Worked well for variable distances necessary. Lasers were a real innovation for timber cruising in big timber.
Excellent presentation
My father was a graduate of the Penn State school of Forestry in the 1950’s. I grew up physically running cruise lines, and by using a Biltmore stick to calculate how much board feet of timber was in an area of land…hard work because one had to stay on as straight of course as possible and this meant transversing around swamps, up hills, etc. we also used paint guns to mark which trees were to be harvested….GOOD TIMES 🙂
Dang!🤠👍
Is there an actual title that goes with that job? Down here we say “that guy cruises timber for a living”.
@@jcook7148
No, but I could get you a bill of sale.
(Knuck knuck knuck!)
@@jcook7148 I'm from Minnesota and that guy is called a timber cruiser. I remember when I was a kid walking on trails marked by axe marks on a trees to keep you on the trail or the "cruise line."
Good video using good old trigonometry. Your hand assessment would be closer to your laser measurement by noticing where on the tree your extended "level" arm was pointing at. You would add the distance from that spot to the ground to your tape distance. In your case on level ground it is 4 feet. This works pretty well when you are standing on the upper side of a hill.
Geometry
Not even trig. Similar triangles. Geometry. 7th grade stuff that many forgot or didn't see as interesting back then.
great knowledge, just learnt something new today
I love that demonstration
Seems like if you add in the distance from the ground to his shoulder that error would only be about one foot instead of four.
That's brilliant! Thank you.
I was expecting some trigonometry, but this is way easier👍.
He is actually using trigonometry, but with paralellism he can just walk around and measure it.
The principle is the same,
Wow! Neat trick! Thanks for sharing.
Awesome, will try this out.
Would it have made a difference if you had held your arm parallel to the ground, then added the distance from your arm to the ground to the measured distance to the tree? In other words, did the negative angle you introduced by aiming your arm at the tree base have given you the four foot error?
Learned to do this with an ax handle from a logger friend of mine, we were just measuring roughly how far the tree will fall when we cut it to determine how far the felled tree would land for hazards but it's cool that we can use this same technique to estimate height if we have a tape
the top would have fallen where he stood.
I dont know when i will ever need this information, but im glad i know it
Great stuff, cheers.
Interesting way of doing it. I always just stood next to it at 6 ft tall and eyeballed 6 ft sections all the way up and added one more than I counted. Then stepped off that distance. Usually ended up being slightly shorter than I measured. Prob shouldn’t be felling the tree that close to anything you don’t want damaged anyway and should climb it and take down in sections.
Alternatively, if you go to the top of the tree, and you hold the end of a 100% straight 90 degree strip of measuring tape that begins right at the base of the tree, you can get pretty accurate results that way too and with only a small risk of bodily harm.
Or you could just cut the tree down and measure it from base to top without ever leaving the ground
Or you can jump off the top and use Newton's equation to calculate the distance based on time in free fall. 9.8m/s2 works.
Great video! I’m going to try this
nice to know, thanks really enjoy these little tricks
I just push a friend out of the tree and count the length of his scream! The sound of the thud is also a good ground penetrating radar tool.
What are you both doing in the tree at the top of it 😂
What happens if tree is on a slope? Do you need to try to stand on the same counter as the tree? For example,
if you stand upslope from a tree, do your thing with yardstick, and measure along (sloped) ground with vinyl tape,
will you still get a reasonable estimate?
nope you just stand next to the tree that's all duhhhh
Good information. I'll definitely remember this.
That was really interesting and informative. WOW! That was cool.
If I am not mistaken you do not need a yard stick. Any stick, branch, log or object of arms length will work. I think you could also bend your arm to 90 degrees and sight down your upper arm to the tree base and then sight across your finger tips to the tree top. Then measure to the tree by knowing the length of you steps. Less accurate but probably within a few feet with practice.
you may not need a yard stick but apparently a hard hat is required 😁
Your forearm may not be the same length as the rest of your arm, how dare you advice something so flawed.
Student's: Why do I need trigonometry
Teacher: You'll be measuring a tree one day
Teacher: "You need trig for a lot of things. But if you want to measure a tree, all you need is geometry"
Excellent Excellent Excellent video! THANK YOU.
Very interesting and informative. Thank you
I was taught to measure the length of my shadow when it was the same as my height, then measure the length of the tree's shadow. Doesn't work without the sun or in a heavily forrested area but it is accurate
You would have to be measuring at exactly the right time of day though. You could also just measure the shadow length of anything you know the exact height of, calculate the difference and apply the same calculation to the tree’s shadow. This can be done anytime there is a shadow present, regardless of its length.
@@cd7071 If you're 6 feet tall and your shadow measures 6 feet it's the right time of day.
@@peterk8909 so that means you going to stand around all day measuring your shadow until it is exactly 6 feet? That would definitely work, but doesn’t sound very practical.
@@cd7071 Not really. It happens twice a day. It's a lot easier than climbing a tree with a tape measure.
60ft actual minus 56ft est. = 4ft
Shoulder height at which stick bottom mark was being held... maybe 4.5 to 5ft?
I suspect for trees around the 45-65ft mark, using the stick method, such slight over-estimate (between 5 to 10%) would commonly happen.
Of course the precise geometry is not quite that simple - and it is after all a rough working estimate.
But just thought I'd make that observation. Anyhow assessment with a small over-estimate is always better re safe working and property protection eh?
I concur.
Great Video! Love it!
Really good work here..nice
Pretty accurate. Correct me if I'm wrong, but If you look closely, there was a depression angle (which might cause the 4 feet difference) when you measured the base of the tree with the base of the ruler (because of this the angle won't be 45° anymore) since you were looking down from the horizontal line, from that viewport (which based on the data was approx -5.14°: tan-1 (5.5/60) based on average human height). If you look absolute horizontal from the eye's POV, there's no way to see the base of a tree. You can only see the base of the tree if there's an opening angle (elevation or depression method, further you go, the more field view will be covered with that same angle). To use this method more accuaretly, our eyes should be on ground level, looking up to the tip of the tree, and measuring the distance right from the point where our head was. The easiest way is to get a rectangular ruler with a degree of 45°, hold it to your eye's height, follow the hypotenuse until you can see the tip of the tree. Measure the distance to the tree and add the height from the ground to your eyes and you get the most possible accurate measurement done without any tech tools. :)
Also, if you looked at the person when he took the tape measure to the tree, he held it up at least three feet above the ground which almost completely accounts for the 4 foot difference from the laser measurement.
@@heela188 doesnt matter that he held over the ground since we are meassuring along that plane the whole way. The difference in height cant be explained this way :)
@@lollerskatez1 The height of his arm above the ground might account for the 4ft difference between the two readings perhaps?
I just hold out my thumb, then paint the tree on the canvas and that's how tall it is!
That's good information. Thanks.
Very fun video. Thanks for sharing. Cool trick to show the boys next time I’m at the cabin:)
Pythagoras's theorem is always useful.
This is how the height of the pyramids were determined by the ancient Greeks. They used similar right angled triangles and shadows cast on the ground.
The method shown is "almost" correct. The reference item is the yardstick (or stick or string & plumb-bob, whatever)...NOT your eyeball. You need to subtract your outstreched arm length (30") from the reading on the tape measure. Also, the Mark-1 human eyeball is way more precise than the laser sensor on your contraption. Swaying tree tops, less upper foilage to reflect light, etc can spoil the lasing meter. Any tilt to the tree can spoil the actual measurement.
i think the point of this video is for a quick estimation, not a precise measurement. Notice how he performed no math in the example
I disagree about the reference point NOT being his eyeball. The reference point is the hypotenuse/adjacent side 45 deg angle of the "Small triangle". That point is ~30 inches from the right angle (arm L yardstick). That's approximately his eye.
I use to use a speed square on a level bucket. Keep backing up until the angle lines up with the top of the tree then measure the distance to the tree. But that's a good trick!
Thanks for the knowledge 🫡
new skill learned at 2 am
I learned a similar method in the Boy Scouts 53 years ago at age 12. Site on the base of the tree with straight object (stick will do) and the top the tree, pivot the base of the stick 90 degrees to the tree! Site on end of the stick that was the top of the tree.
Have someone mark that point while you are still sighted on the stick. If you were to fell this tree in that direction that is where the tree would land.
were you 17 then ?🤣
That’s very handy to know. Thankyou
Really handy short cut!😊
I like how they are wearing hard hats on a public sidewalk
I think I can estimate the tree height just by looking at it and come as close as you did.
As a member of a remote control airplane club, I often help people get their airplane out of a tree. Sometimes I use a 100 foot parachute chord. If I get the chord over a branch and it just reaches the ground I know it is 50 feet up. I can add more rope as needed if it is over 50 feet. I can usually guess within 5 feet of how high up the target is.
yeah man It's pretty easy to know the height of a tree lmao. I dont know why these are complicating it
@@iamf6641 Probably because most people are not good at estimating things. And lets be honest, most men don´t even know the difference between 6 and 12". :p
Finally, something educational that the algorithm has recommended!!!!
Thanks, great video
Interesting. Are conquistador helmets the required head covering at your college campus?
Interesting! In my previous line of work we were never really concerned with tree height, only tree diameter.
Great work keep it up
Well....you measure the height of a tree very carefully. That is how I was taught back in the 1970's....
You all take good care out there now you hear.
That’s just more complicated than it needs to be. Keep it simple, just site at a 45 degree angle to the top of the tree, take a step back and the top will land at your toes. ( use a hand held site level with 45 degree mark if You can’t judge it)
i agree, a bucket of water works perfectly too
Thats too complicated, just climb the tree and drop down from the top, calculate how long it took to drop and bobs your uncle, you got your height
What you describe is exactly what he did. I don't know how it could get less complicated.
Great video
Many years ago while I was deployed, we were trying figure out the height of a flagpole. A young civil engineering officer only ‘sort of’ remembered this method, so we relied on other means. But I’ve always held it in the back of my head and though it would be cool to know. Well, now I do.
Hello Paul how are you doing 😊
You're a professor but didn't throw in the basic reason this works the way it does? Come on man. It's simple geometry, you're creating a 45 degree angle from where you're standing with the tree, and the angle is equidistant and therefore the same length as the vertical tree as is along the ground to it. Think of a speed square, you're creating a gigantic invisible one between you and the tree, with your feet at the point of the 45 point
John Bell explained this in a most professional and empathetic way. OSU has the BEST Forestry Engineering School available in the USA.
That’s excellent!
I wish there was an app full of this kind of stuff. Would be gold
I have something similar that can do that. "Theodolite" (iPhone) takes photos/videos that will stamp the image with GPS location, direction, tilt, azimuth, time and date. I imagine you could even take a measurement of a tree on the other side of a small river. Take one reading, go farther or closer and take another reading, compare the two angles and distance between the two points.
Very interesting, thank you.
I was worried they wouldn’t wear the appropriate safety gear when performing this dangerous task. I felt great relief to see they indeed were wearing hard hats.