[Tagging] Tagging National Forests

[Daniel Koć]

W dniu 17.08.2015 4:10, Martijn van Exel napisał(a):

> But after some discussion I realized that this may be a side effect of
> a different problem, namely how we tag national forests. In the US,
> these seem to be tagged as landuse=forest which is only partly true:
> within a National Forest, many different land uses can occur, only one
> of them being forest.

We had the same problem with imports of national forests in Poland. It's 
exactly the counterintuitive problem you've mentioned: forest area is 
not always covered with trees! In our case that was probably just areas 
being property of the national forest operator "Lasy Państwowe" (which 
is the same as "National Forests" by coincidence =} ).

> So should we just not tag National Forests as landuse=forest?

We started redrawing the boundaries, so the forest is just the ground 
truth (only the trees), but now I'm not sure that was the best action to 
take, even if simple and useful. Somebody lately said, that the forest 
area may include burned areas, young trees fields and other such things. 
I'm not into the forestry, but it looks we have the opportunity to 
redefine our trees/forest tags, starting from general understanding what 
the forest really is and what parts it consists of. While discussions 
about landcover=trees are useful, they are way too narrow. I feel we 
need to rethink the whole tree tagging in OSM, because we have no 
general agreement on the subject:

http://wiki.openstreetmap.org/wiki/Forest

The whole issue is not as straightforward as one can reasonably expect. 
According to Wikipedia:

"A forest is a large area of land covered with trees or other woody 
vegetation.[1] Hundreds of more precise definitions of forest are used 
throughout the world, incorporating factors such as tree density, tree 
height, land use, legal standing and ecological function.[2][3][4] 
According to the widely-used[5][6] United Nations Food and Agriculture 
Organization definition, forests covered an area of four billion 
hectares (15 million square miles) or approximately 30 percent of the 
world's land area in 2006.[4]"

The FAO definition is linked:

http://www.fao.org/docrep/005/y4171e/y4171e10.htm

and it has about 17 pages on my screen. Actually it's rather good that 
it is so comprehensive, because it may be a good base for understanding 
the background and to identify parts we may be interested in. Another 
idea is to research common GIS practices regarding trees.

Anybody willing to get deeper into the subject?

-- 
"The train is always on time / The trick is to be ready to put your bags 
down" [A. Cohen]