[Tagging] Feature Proposal - RFC - boundary=forest(_compartment) relations

[Kevin Kenny]

On Wed, Feb 10, 2021 at 8:52 AM Martin Koppenhoefer <dieterdreist at gmail.com>
wrote:

> Am Mi., 10. Feb. 2021 um 13:47 Uhr schrieb Paul Allen <pla16021 at gmail.com
> >:
>
>>
>> The forestry proposal emphasises that its boundary may encompass
>> areas of not-trees: lakes, rocks, cleared ground where trees have
>> been felled and new trees have yet to be planted, etc.
>>
>
>
> I believe it is not helpful to include lakes, rocks or scree in "forestry"
> areas. I can understand that from a macro perspective, in a "forestry" area
> there might be lakes, e.g. if you say "the Amazon rainforest is a forestry
> area" (exaggerating here to make the point) but going more into detail, you
> can hardly argue that a lake is used for forestry, or scree. In OSM we tend
> to expect that the macro view is represented by analyzing the detailed
> mapping. We generalize as few as we think makes sense (and according to the
> time we dedicate), but in principle we strive for a high level of detail,
> because you can always compute more abstract generalizations, but you can
> never get detail that isn't there.
>
> I also do not believe it is helpful to see sawmills as part of forestry.
> We do not see furniture factories as part of residential landuse, do we?
>

Which then once again leaves us with no way to map a designated, signed
boundary of an area reserved for forestry.

Around here, those areas do indeed include rocks and scree, some of which
in a few decades may have trees. If, for instance, an avalanche scar isn't
scree or rock, what is it? But they eventually regrow.

Also, the areas do include many ponds that last for a while, and then
eventually drain when the beavers move on.  They then go through natural
succession through mud flat, meadow, alder thicket, and eventually regrow
to young forest that's attractive to the beavers again. Sometimes the young
forest gets harvested along the way. Some of those ponds are fairly
sizable.  https://www.flickr.com/photos/ke9tv/14966947604/ shows where a
trail was wiped out by beavers and
https://www.flickr.com/photos/ke9tv/15563983656/ gives an idea of the
extent of the inundation.  https://www.flickr.com/photos/ke9tv/15587818865
shows an early stage of succession where plant life is returning to a spot
the beavers have abandoned - predominant vegetation here includes grasses,
sedges and cranberries, plus some tamaracks that have survived from the
previous cycle. https://www.flickr.com/photos/ke9tv/15541120652 is later in
the succession, with alder, shadbush, and a few beech saplings appearing.
Much later in the cycle, I don't have good pictures to show you because the
thickets are not terribly photogenic.

When I was a young boy, a piece of my uncle's property was under the waters
of a beaver pond, and I would fish there when I visited him. By the time I
was a grown man, the pond and the beavers that made it were gone, replaced
by a sucking mud flat.  By the time I married, there was a grassy area with
patches of laurel meadow. When my uncle passed away, and the property came
into the hands of first my mother and then my brother, it was a diverse
thicket of alder, blueberry, shadbush, and other early-succession species,
with tree saplings beginning to emerge. Today, young pines stand above the
scrub, which is beginning to struggle. It won't happen in my lifetime, but
my daughter will likely see tall pines and birches standing where the pond
once was, and all the early-succession plants shaded out. In another
generation or two, the oaks and hemlocks may begin to take over, if the
area is undisturbed, or else the beavers will move in again. The same thing
is now happening in some adjacent land where my brother harvested a fine
stand of red oaks, about twenty years back. That's the time scale that
forestry happens in.

All of these areas are part of managed 'forest'. It's worth mapping where
the ponds, marshes, meadows, screes and scrub/shrublands are this decade.
It's also worth mapping the forestry area, particularly if it's also
designated in some way for public recreation.

There are large commercial forests - privately held - in my part of the
world that do have recreational easements. There are even larger state
forests that the timber companies contract with the state to harvest. The
public policy that created them is there to ensure sound management. Prior
to their creation, the land was laid waste by an endless cycle of
clearcutting and bankruptcy. Eventually it became clear that the state
should simply hold the land that it had seized when the bankrupt logging
company ceased to pay taxes. More recently, (but still generations ago) the
state realized that there's value in having recreational access to the
managed forest, and now most pf the state forests are managed for combined
objectives - soil and water conservation, species protection, fish and
game, timber, and recreation, at the very least.  I think that there's a
fairly broad consensus that cadastral mapping is acceptable for such things
as recreation areas, particularly where the boundaries are marked and
recoverable in the field.

There's a proverbial phrase in English. When someone gets so embroiled in
details that he loses sight of the big picture, we say that he 'can't see
the forest for the trees.' That's exactly what's going on here. The trees
are the detailed landcover - useful to map. The forest is the designated
landuse - also useful to map. Confusing the two is what got us into this
mess in the first place.
-- 
73 de ke9tv/2, Kevin
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