[Tagging] Multipolygon (several outers) forest with different leaf_types: mapping strategy?

Joseph Eisenberg joseph.eisenberg at gmail.com
Wed Mar 13 23:36:58 UTC 2019

Normally we should map features that are “real” and “current”, and is
easiest to do for things that can be observed in person.

This suggests mapping each patch of trees as a separate polygon or closed
way, based on having the same leaf_type and leaf_cycle. Usually it’s only
necessary to use a multipolygon when there is a hole in a donut-shaped
woodland. Each area should be tagged natural=forest or natural=wood in
addition to the leaf_type/leaf_cycle tags

So then the problem is, how do you show that all of these patches of trees
are part of one “forest”?

How can another mapper verify where the named “forest” ends? Is it a type
of boundary=protected_area that is designated by the local government or
private landowner? Is there a fence around the whole area? It looks like it
is not a single continuous area, so this makes it even harder to verify
where the named forest ends.

I don’t know much about the original poster’s example, but it looks like
the name is “<Village name> Communal Forest”, and the areas included in the
relation are on separate sides of the village and divided by farmland.
Also, there are other areas of woodland right next to the edge of this

Perhaps this is mapping land ownership parcels rather than a “real”
physical feature?


On Wed, Mar 13, 2019 at 11:14 PM marc marc <marc_marc_irc at hotmail.com>

> Le 13.03.19 à 14:59, David Marchal a écrit :
> > the JOSM validator claims that contiguous outer members is an error
> yes it's- the sum of all outer should not have a "internal" way
> like this one
> https://www.openstreetmap.org/relation/9393253#map=17/48.42219/5.92713
> so draw a new way for the outer of this part
> or split currents ways to include only the outer part in the relation
> and make another relation for the leaf_type
> > openstreetmap.org renders a misplaced name
> It doesn't seem so misplaced
> https://www.openstreetmap.org/#map=15/48.4222/5.9197
> but that's not due to the tag
> > no leaf_type
> it's hard to render a forêt with several leaf_type
> you may put natural=wood landcover=trees to every part of the forêt
> having a different leaf_type
> but you 'll have a duplicate forest : a foret at the relatin level and
> at every part. currently i'm not aware of a good schema to avoid this
> (you can trick some QA tools by using landuse=forest for the
> relationship and natural=wook for all parts, but see the wiki for
> forest, the meaning of these 2 tags is random/variable depending on the
> mapper, the only meaning you can get is "there are trees", the same
> meaning for the 2 tag)
> Regards,
> Marc
> _______________________________________________
> Tagging mailing list
> Tagging at openstreetmap.org
> https://lists.openstreetmap.org/listinfo/tagging
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/tagging/attachments/20190314/0403e6ed/attachment-0001.html>

More information about the Tagging mailing list