Mapping Software (BS5837 Utility)

[Paul Barton]

Out of interest, does anyone know why the RPA of multi-stemmed trees should be less than for single stemmed trees?

 

The BS doesn't detail why the calculation is different - I wondered if anyone knew of any evidence that multi-stemmed trees have a smaller rooting area?

[Amelanchier]

Out of interest, does anyone know why the RPA of multi-stemmed trees should be less than for single stemmed trees?

 

The BS doesn't detail why the calculation is different - I wondered if anyone knew of any evidence that multi-stemmed trees have a smaller rooting area?

 

I would guess that because the measurement is taken at the base (where even a multistemmed tree usually has one stem/root collar), it's to compensate for the lack of taper.

[benedmonds]

 

 

Giles, have you/would you also add shadows and max height and spread to the trees? The Tree life BS5837 course recomended that you do.... I'm not sure I agree but interested in what others do/think.

[christreeroot]

 

 

Giles, have you/would you also add shadows and max height and spread to the trees? The Tree life BS5837 course recomended that you do.... I'm not sure I agree but interested in what others do/think.

 

 

We add these to certain jobs if they merit it, also you have got to take budgets and what the client wants.....

[Paul Barton]

I would guess that because the measurement is taken at the base (where even a multistemmed tree usually has one stem/root collar), it's to compensate for the lack of taper.

 

Of course! Obvious really

[Giles Hill]

 

Giles, have you/would you also add shadows and max height and spread to the trees? The Tree life BS5837 course recomended that you do.... I'm not sure I agree but interested in what others do/think.

 

 

I take the same approach as Chris. I did notice the software originally mentioned seems to do shaddows quite nicely.

 

The max height and spread would sometimes be a tough one to estimate, because of the environmental variables. You could have reasonable stab at it, if there where existing mature trees of the same species nearby, but I'd have a job providing much more than a guess, if it was the only tree of it's kind.

 

That said, I'd bring the subject up if it was a particularly worthy tree that wasn't fully mature - it's something that I'd do on occasion rather than for every tree.

 

The other 'non-BS' thing I tend to do, is just measure the spread where it's relevant rather than in all 4 points of the compass - eg if the tree is one of a group that's going to be retained, I don't measure the sides that are growing into neighbouring trees, just the sides that are overhanging the site. Firstly it's sometimes impossible to tell where one tree canopy starts and another finishes, so making up a measurement to fill a blank space on a form is pointless and secondly I think allows a better graphic representation - i.e. the group becomes an entity rather than a collection of oddly shaped trees. (If that makes sense).

 

Likewise I don't usually measure parts of the canopy that are overhanging neighbouring land - unless there's a reason to do so.

[Bundle 2]

"The above image is taken from the mapmaker site - it alters the shape of the RPA quite nicely, by extending the arc away from the barrier, whilst maintaining the overall area. "

 

"Any way, it’d be nice to have some software that drew the odd shaped canopies on AutoCAD rather than doing them manually. "

 

If map maker can do the rpa then why not the canopies.....?

Just reading the Pear Technologies blurb...it states that PT-Mapper Pro calculates to 4 compass points...so then it will draw eccentric canopy outline surely....Anyone know?