Talk:Tag:natural=gully

Why not use with waterway=stream ?

We have no fitting landform or attribute to say that a stream is in a "cutting". Many people use waterway=ditch which is wrong, this one might be better? RicoZ (talk) 20:15, 23 September 2018 (UTC)

waterway=stream + cutting=yes is a valid combination but cutting=yes indicates an artificial cutting.

Combining waterway=stream + natural=gully? - why not. --Imagico (talk) 20:33, 23 September 2018 (UTC)

it is not entirely clear what is meant by "stream is in a "cutting "". The gully is well described in Wikipedia. It is a form of soil erosion. The gully usually does not have a permanent watercourse, but it can be formed by water during the melting of snow.

--EugenyN (talk) 20:40, 23 September 2018 (UTC)

I mean a stream in a gully. A permanent stream in a gully may be unusual but I see nothing in the WP article prohibiting it and I would consider the combination(s) as indicated by Imagico a valuable option regardless how rare.

Any objection if I remove the "should not be used for: small valleys with known permanent or regularly occurring waterflow" part from the tag description? I consider it an unnecessary restriction. RicoZ (talk) 18:09, 25 September 2018 (UTC)

if there is a stream at the bottom of the gully, then it is possible to use waterway=stream + natural=gully, however I personally have not seen it. it would be interesting to see the photo.

it seems the wiki about the gully is a translation of the russian wiki. there is no recommendation "should not be used for: small valleys with known permanent or regularly occurring waterflow" there

I think we should use natural=gully when the landscape erosion is primary. if the stream is primary it's better to use waterway=stream + clarifying tag.

Also in the russian wiki it is noted that natural=gully it is desirable to use for narrow gully. (1-5 meters) if the gully wide it is better to use natural=earth_bank --EugenyN (talk) 18:46, 25 September 2018 (UTC)

You are suggesting waterway=stream + clarifying tag - do you know a suitable clarifying tag? Because that is exactly what I would use natural=gully for. Regarding the conflicting width suggestions and natural=earth_bank we could reword the pages in the sense "if the erosion area is large enough that it can be mapped in detail you can use natural=earth_bank instead".RicoZ (talk) 19:08, 25 September 2018 (UTC)

Unfortunately, I do not know the qualifying tag. And I do not really understand which natural object is going to be tagged. it would be nice to see the photo.

"If the erosion area is large enough to be displayed in detail, you can use the natural = earth_bank instead." Yes, this is a correct remark.--EugenyN (talk) 19:19, 25 September 2018 (UTC)

Not so easy to find a fitting example picture but perhaps [1] or if you imagine a miniature version of [2]. RicoZ (talk) 19:52, 25 September 2018 (UTC)

thanks for the photo. in photo 1 I definitely see a gully. judging by the size (width) it is probably natural=earth_bank. also judging by the picture it is early spring and the stream will exist until the snow melts, probably 1 month or less. --EugenyN (talk) 16:38, 26 September 2018 (UTC)

Yes, it could be tagged as natural=earth_bank if it is visible good enough on the satellite picture or someone walks along the banks with a gps. Otherwise it would be still small enough it could be still mapped as gully (at least according to the English page). RicoZ (talk) 19:01, 26 September 2018 (UTC)

The cited statement was meant to indicate that a stream incised into the surrounding soft ground should always be mapped waterway=stream and that natural=gully is not a replacement for this. I would suggest to add back a statement that unless the hydraulic erosion that led to the formation of the gully is strictly historic and there is no present day water flow continuing the erosion waterway=stream (+ potentially intermittent=yes) should be used. --Imagico (talk) 10:19, 26 September 2018 (UTC)

Confused .. why not waterway=stream + natural=gully (+ possibly intermittent)? Or is that what you are suggesting? RicoZ (talk) 19:01, 26 September 2018 (UTC)

Ah, too bad I just now read the comments here - could have taken photos of a few gullies with streams in them in today's hike :) We have plenty of those in Latvia. Some indeed are seasonal, getting water when snow melts. But many have formed on the banks of the ancient glacier riverbeds, where small springs appear. In that case, it's a permanent small stream that digs a gully. It definitely makes sense to map gully + stream on the same way. Sometimes either the stream or the gully might be longer than the other, which can be handled by split or partially overlapping ways (no strong preference). --Richlv (talk) 20:54, 21 January 2023 (UTC)

Transitional Landform

I know many places here in Austria that look very much like the sample photo. All of them are the consequence of terraces that were made for agriculture (vineyards etc.). Some of them were later abandoned and reforested, but you can still see the terraces. On heavy rain, the water now digs easily into the soft soil, and the first step in the transition back to natural landforms with valleys and ridges is what we see in this photo. If the terraces are still in agricultural use, the farmers throw green and other waste into the gullies. Otherwise, they become deeper and deeper over the centuries and the slopes become wider and smoother, and in the end there is a valley.

Similar ravines (but not as narrow) can develop from former hollowways. --Fkv (talk) 21:23, 4 August 2020 (UTC)