[Talk-us] misuse of the landuse=forest tag for national forests

Torsten Karzig Torsten.Karzig at web.de
Sat May 11 22:43:51 UTC 2013

Hello SteveA,

Thanks a lot for your reply. I really appreciate you work for updating 
the national forests in southern California.

Before posting I already read the wiki pages you mentioned. For me it 
seemed that there is still some dispute about how the tag landuse=forest 
is used and there exist different approaches. What I only learned now is 
that US National Forests are indeed used for timber harvesting (and not 
only for forest protection) so I now fully agree that the natural=wood 
tag is inappropriate.

However, one thing which I still find strange is to tag large areas of 
scrub (bushes without any trees) as landuse=forest. Somebody using the 
map may be surprised when not finding any trees in a region mapped as a 
forest.  [The parts of the Angeles National forest that I have seen so 
far are dominated by scrub] For me using the landuse=forest tag in this 
case seems to contradict the fact that landuse=forest is supposed to 
describe woodland.

In an ideally detailed map those parts would be marked as scrub. For me 
it seems that what to do in the current situation is a question of what 
to take as a default. Your point of view is marking everything as 
landuse=forest and manually excluding scrub land. I thought it would be 
better to only mark parts as forest which clearly are woodland. Since 
your point of view seems to be the standard practice right now, I agree 
that it is probably the best to stick to it (although this means, imho, 
ignoring the conflicting definitions of scrub and forest).

Buy the way, what is rendered when a region is landuse=forest and 
natural=scrub at the same time?



On 05/11/2013 01:59 PM, stevea wrote:
> Hello Torsten:
> Please see our wiki page regarding these data (USFS imported data for
> national forests and wildernesses) at
> http://wiki.openstreetmap.org/wiki/US_Forest_Service_Data.
> Please see our wiki pages at
> http://wiki.openstreetmap.org/wiki/Tag:landuse%3Dforest and
> http://wiki.openstreetmap.org/wiki/Tag:natural%3Dwood regarding the
> differences between forest (actively managed forests where timber
> harvesting can and does take place, whether publicly or privately
> owned), and wood, which is "for ancient or virgin woodland, with no
> forestry use."
> Quite arguably, all national forests ARE landuse=forest:  in my mind
> there is no clearer example of a landuse tag as "forest" matching so
> well as exactly those of the boundaries of national forests.  Also
> arguably, there are NO natural=wood polygons which would be appropriate
> in any national forest, as they are managed forests, not "ancient or
> virgin woodland, with no forestry use."  These two categories are
> mutually exclusive.
> The protected_area tags are correct, on that we seem to agree. However,
> if there are other natural areas in such protected areas as national
> forests, which are correctly tagged landuse=forest (managed timber)
> which have other natural coverings, such as scrub or heath, you are
> perfectly welcome to add a natural=scrub tag (or whatever) where those
> natural landcovers are found, as appropriate.  Landcover is an emerging
> edge of OSM semantics, and there is much discussion about it:
> http://wiki.openstreetmap.org/wiki/Landcover is a good introduction, and
> http://wiki.openstreetmap.org/wiki/Proposed_features/landcover discusses
> a major proposal now under way.
> Also, http://wiki.openstreetmap.org/wiki/Protected_Area_Rendering shows
> that protected_area=6 (as national forests are/should be tagged) has
> specific polyline and dashing rules, but this (these rules) is/are
> proposals for the Kosmos renderer only.
> No, natural=wood is not a "better" tag (whether in replacement or as an
> additional tag) to the tag of landuse=forest for national forests. There
> is no interpretation here:  as described above, natural=wood and
> landuse=forest are quite mutually exclusive.
> SteveA
> California
> (who recently uploaded the southern California national forests, with
> careful tagging and discussion both here and in the first wiki page
> mentioned above before doing so)
>> I am relatively new to the talk-us list and have a question concerning
>> the landuse tags of national forests. Right now (at least in southern
>> california) all national forests are landuse=forest which leads to
>> large green areas on the map which look like they originate from a
>> very old video game with giant pixels. The boundaries of the national
>> forest often have nothing to do with the actual
>> landuse=forest/natural=wood boundaries. I would therefore vote for
>> deleting the landuse tag [and map it separately] leaving the national
>> forests only as protected_areas.
>> Before doing this change I would like to have your input/opinion on
>> the topic.
>> I know that this should actually not be a concern but does anybody
>> know whether protected areas of level 6 (like national forests) are
>> rendered? (if not this might be a reason for the initial
>> landuse=forest tag, although this is clearly mapping for the renderer)
>> One more thing: When I look at the definition of the OSM map features
>> it seems that natural=wood seems to be a better tag. But this depends
>> a bit on the interpretation whether landuse=forest is used for land
>> that is primarily managed for timber production or for woodland that
>> is in some way maintained by humans.
>> Torsten

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