Measuring lean

[daltontrees]

2 nails and the clinometer app on a smartphone

https://play.google.com/store/apps/details?id=com.plaincode.clinometer&hl=en_GB

[Daniël Bos]

Is it wrong to be a little excited about this coming storm, just so I can measure afterwards to see if anything moved?

[Gary Prentice]

Is it wrong to be a little excited about this coming storm, just so I can measure afterwards to see if anything moved?

 

Very.

[Daniël Bos]

On the subject.

When I screwed in the screws the distance between the two was 297mm.

About a week later the distance was 295mm (which would be less lean???)

Both of those were on perfectly still days, the second measurement a day after heavy rain.

Today it's been gusty, and the measurement varied between 292 and 299mm which lead me to the question: is there readily available data on how much a particular species of tree, of a particular diameter can naturally flex?

I presume it was just flexing in the wind, I couldn't see any rootplate movement, but I don't know if I'd be able to see such small movement if it was rocking it's roots? Also the half I'd be wanting to look at most is under that building.

[Daniël Bos]

The building hasn't moved by the way, it's a straw bale, cob plastered structure. Any movement would show cracks in the plaster.

[Daniël Bos]

The only issue I have with the smartphone option, is that I use it to document the data.

I take a picture of the plumbline or the tape measure. It then has a time and date attached.

If I use the phone to measure angle (mine has perfectly straight sides btw) it can't take a picture of itself.

 

First world problems, but problems still...

[sandspider]

Take a screen grab? That'll show what's on the phone screen with time and date...

[Daniël Bos]

Three years on, here's the "field" tree.

It looks to have moved about an inch, which given the distance over the measurements would be an increase in lean of approximately 0.45 degrees.

Considering the position of the tree, it's vitality, and the targets should it fail, I'm quite happy with that.

 

From the picture it may not be very clear, the tree has just one single branch on the "high side" which actually doubles back towards the low side to such an extent that I reckon it's net contribution to counteract the lean is zero.

Edited March 11, 2020 by Daniël Bos

[Daniël Bos]

The tree by the building may have moved just a tiny bit.

Gap between the screws now measures 297 ish mm.

Took me some time to find the same tape measure for consistency...

 

It appears to be in slightly less health overall. Most likely because of the very dry past two years (with half it's root plate covered by the building) and the very Sandy soil.

There's little bits of Browning of the needles throughout.

Hopefully with a slightly less dry summer for a year or two she'll recover.

 

So far, I'm happy to retain this one also. Though it would be unfortunate if the building got damaged, it's not in use often and failure of the tree would not likely result in injury or worse.