[Tagging] eelgrass

[Joseph Eisenberg]

Ok, looking at the aerial imagery at
https://www.openstreetmap.org/edit#map=16/48.4961/-122.4876 - this is
certainly not a reedbed. Reeds have long woody stems which stick up
out of the water, and they are a significant barrier to travel. Even
wetland=saltmarsh would be inappropriate, because a salt marsh has
grasses and similar plants which extend up out of the water. But in
this area you can travel freely by canoe or kayak, because the
seagrass is under water in all of the aerial imagery.

It looks like this are is above the lowest low tide line, is that
right? But perhaps there is just no imagery from low tide?

If the area is, in fact, exposed at low tide, then it would be okay to
keep the natural=wetland and use a new tag wetland=seagrass for the
areas that are covered with eel grass or similar vegetation, since
wetland=tidalflat implies no vegetation:
https://wiki.openstreetmap.org/wiki/Tag:wetland%3Dtidalflat

If there are deeper areas of seagrass which are not exposed at low
tide, I would not map these with natural=wetland, since they are
always covered in water even at the lowest tides. But you could map
these areas with a new tag like natural=seagrass if the eel grass is
clearly visible from the surface or in aerial imagery.

Joseph Eisenberg

On 12/19/19, Clifford Snow <clifford at snowandsnow.us> wrote:
> On Wed, Dec 18, 2019 at 1:00 PM Joseph Eisenberg
> <joseph.eisenberg at gmail.com>
> wrote:
>
>> Do you have an example of a location which you wish to tag?
>>
>
> Here is what the researchers have documented
> http://www.arcgis.com/home/webmap/viewer.html?url=https://services.arcgis.com/6lCKYNJLvwTXqrmp/ArcGIS/rest/services/PBNERR_2004HabitatMap_for_Publishing/FeatureServer&source=sd
>
> What is in OSM is https://www.openstreetmap.org/#map=12/48.5094/-122.4945
>
>>
>> It looks like eelgrass usually grows below the low tide line, unlike a
>> salt marsh, and the grasses do not usually reach up above the water.
>> So natural=wetland might not be appropriate for these seagrass
>> meadows.
>>
>> Perhaps natural=seagrass would work?
>>
>> https://iucnrle.org/blog/seagrass-meadows-the-marine-powerhouses/
>>
>> https://www.sciencephoto.com/media/728140/view/cape-eelgrass-zostera-capensis-
>> https://newenglandboating.com/bay-scallops-and-eelgrass/
>>
>>
> --
> @osm_washington
> www.snowandsnow.us
> OpenStreetMap: Maps with a human touch
>