[Talk-ca] Mapping cut blocks in "wooded" areas

[Bryan Crosby]

RE: cut-blocks

 

As someone who has spent done time as a forest technician, I strongly advise
against mapping forestry activity.  Cut block spatial data changes daily and
any images used to trace are out of date.  There are literally tens of
thousands of clear cuts in British Columbia alone and there is absolutely no
way OSM mappers would be able to keep up with changes.  Keep in mind that
most clearcuts on crown land (and in some cases, private land) are temporary
openings in various stages forest development.  A 2 year old stand is just
as much a forest as a 25 year old free-to-grow stand or a 250 year old stand
of timber.  I believe that mapping a privately held 'Christmas' tree farm
would be pertinent, but these are radically different from commercial
forestry openings.  

 

I would also advise extreme caution in using images to map forest
development roads unless are working on a high traffic mainline.  Many spur
roads are in various stages of deactivation.  It may look like a road from
the outdated image, but it may have been completely deactivated and
replanted.  A site inspection is the only way to be sure.  

 

Bryan

British Columbia

 

From: Daniel Begin [mailto:jfd553 at hotmail.com] 
Sent: March-04-11 8:19 PM
To: 'Samuel Longiaru'; 'talk-ca'
Subject: Re: [Talk-ca] Mapping cut blocks in "wooded" areas

 

Hi Samuel,

 

About tagging forested areas, I would use landuse=forest only if it is
obvious on the field that the area is managed/harvested, as for
landuse=orchard or landuse=vineyard. We have a lot of Christmas tree
plantations in the area and I map them as landuse=forest because it is
obvious on the imagery and on the field.  

 

If it is difficult to determine if an area is under timber lease or not,
because it looks the same, I would keep it natural=wood...

 

About Cut blocks, I would map the hole they create that wooded area.  If the
area is replanted, then some OSM contributor will remove the hole you map in
10-20 years from now! 

 

Mapping the reality is the best we can do and because the reality changes
over time, we can keep mapping !-)

 

Daniel

 

  _____  

From: Samuel Longiaru [mailto:longiaru at shaw.ca] 
Sent: March-04-11 21:45
To: talk-ca
Subject: [Talk-ca] Mapping cut blocks in "wooded" areas

 

Hi Everybody,

I've been importing CanVec mostly south of Kamloops for the past several
weeks and am going to take some time now to go back and bring stuff up to
date.  One question I have though is in regards to how to treat cut blocks
in the wooded areas.

I see according to the map features wiki, that the CanVec imported tag of
natural=wood is technically not correct, at least for here, as wood is to be
reserved only for completely reserved/unmanaged areas.  I guess most of what
I have should really be mapped as landuse=forest but I have not made the
change because what is under timber lease and what is not would be difficult
to determine.  In one sense it's all managed to some degree or other.  But
my point is rather what should be done with the cut blocks, which in some
areas constitute up to 50% or more of the forested area.
http://osm.org/go/WJ1cj_R is a typical area.  It seems improper to keep them
as wooded when they are clearly not, and yet most are replanted and will be
wooded again someday... or at least that's what they keep telling us.

I started mapping them as it truly gives a more accurate representation of
the current state of affairs on the ground... but thought I'd better get
some guidance before proceeding too far.  

Thanks,

Sam L.
Kamloops 

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