User talk:Imagic/landcover

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Recreation ground vs. park vs. village green

What exactly is the difference between a park (leisure=park), maybe with some pitches (leisure=pitch) and a recreation ground (landuse=recreation_ground)? And why another tag for landuse=village_green? --Imagic 14:49, 20 March 2012 (UTC)

vineyard is an orchard

As far as I understand the difference between plantage and orchard is that orchards are plantages for food production where plantage is a more general term. --Skyper 15:33, 23 January 2013 (UTC)

In my understanding vineyards are orchards and should be in this group with orchard=grape. --Skyper 15:33, 23 January 2013 (UTC)

At first I thought the same. But after some research it turned out that a vineyard is not an orchard. Even wikipedia uses the word plantation. To be absolutely sure I'll ask some native speakers. --Imagic 16:12, 23 January 2013 (UTC)
The first reply from a native speaker confirms this: "An orchard is always a field of fruit trees, (e.g. apples, pears, cherries etc). Other kinds of fruit growing on vines or bushes would not be called an orchard. " --Imagic 16:43, 23 January 2013 (UTC)
Ok, but then it should be stated that way. Right now "trees and shrubs" are mentioned and grapes belong to the second one. --Skyper 17:29, 23 January 2013 (UTC)
I took the definition from wikipedia. But after some more digging I tend to agree with you that "shrubs" is not correct. I'm removing it from the definition of orchard. --Imagic 08:40, 24 January 2013 (UTC)
Also plantation might be a bit too general as it fits for all (forest, orchard, strawberries, vineyard, bamboo, rice, asparagus, horsetail and more). Where is the difference to farmland or should I add the crop sequence by months and tag it as plantation ? --Skyper 17:29, 23 January 2013 (UTC)
I see the point. I guess we need a better differentiation between those three, especially as those terms overlap to some degree. Maybe it would be even better to not give a definition of these terms but instead present a list, what should be tagged with each one. Example: bananas are by definition grown in orchards but they are called "banana plantations". Quote from wikipedia: "The term "plantation" has usually not included large orchards (except for banana plantations)". So lets use each term as it is actually used by people.
And regarding vineyard: I'm tempted to move that back to landuse=vineyard. Most responses I got tell me that they may be plantations but no one calls them that way. --Imagic 08:40, 24 January 2013 (UTC)

I made now the following changes:
  • landuse=vineyard is again a separate tag: it is used a lot and most people don't see it as orchard nor as plantation
  • landuse=orchard should be used for all trees for food production. This is in line with the current description of the tag.
  • landuse=plantation should be used for all trees which are not for food production, e.g. tobacco. One exception: landuse=forest should be used if the trees are grown for timber. --Imagic 14:18, 24 January 2013 (UTC)
tobacco is not a tree, but I think you meant "trees and other plants which are not for food production, e.g. eucalyptus, tabacco". --Skyper 13:40, 25 January 2013 (UTC)
  • landuse=farmland should be used for all plants except trees, e.g. sugar cane.
This is not 100% as the terms are defined but should make it easier to find the appropriate tag and is also (more) in line with the current tagging practice. --Imagic 14:18, 24 January 2013 (UTC)
Better now. Still some thoughts:
  • palm trees are no "real" trees, better mention seperatly (important for translation).
  • Do not know how many people know that e.g. sugar cane and bamboo are grass.
  • Monoculture should be mentioned in the definition of plantation.
  • Last but not least, I find it more and more difficult to distinguish between non-food and food production. All plants where parts can be used to make oil of are difficult. Some plants are also used by the pharmaceutical industry and you also might use several parts of a plant for different purpose.
I already use landcover=* and would like to get it more spread but especially this part is not clear at all and I think that we won't advance with some more redefining and deprecating in favour of a better structure / system. The more people we can convince the easier we will get the developers of the editors to change the presets. (JOSM code includes already a function to warn about deprecated tag and one to silently change tags of modified objects on upload. --Skyper 13:40, 25 January 2013 (UTC)

Rendering order

I am not sure about this strict order for rendering:

  • Within a landuse=* there might be several landcover=* (e.g. grass, scrub in a hole of the forest or on the side of a plantation / orchard).
  • Right know I am not able to tell which should be rendered first as they might even cross it is also not really calculable.
  • Only solution I see right now is to render one of the keys either with some transparency or non-solid or to limit landcover=* to stay within one landuse=* and create several objects where needed. --Skyper 14:08, 25 January 2013 (UTC)
Please keep in mind that these are all just my thoughts about how it might work. This is not - and is also not intended as - a rule book. The specific rules are always up to the renderer itself. Maybe some renderer ignores landuse completely and only renderes landcover - or vice versa. When writing that part I always had some kind of transparency in mind; maybe I should emphasized this more. --Imagic 12:42, 29 January 2013 (UTC)


While I mostly agree with your writeup I think that the following paragraph should be revised: If we take a look at the possible values, we see things like cave_entrance, peak, spring, stone (a single stone), tree (a single tree), volcano, but also scrub, water, wetland, wood, etc. There is no clear idea visible, for what this key should be used.

In my understanding this should be used for natural one-dimensional features. This of course would deprecate about half of the values.

I think that a scrub, a wetland (eg a marsh, a swamp) or a wood could be seen as geographic objects similar to the point features. There are also linear features like cliffs that fit into this view of natural. These are typical objects to put a name (while inside there might be several landcovers and landuses, maybe without names). What does not fit into this typology for natural, of the currently used values, is mud or sand or similar.

So there is no gain in restricting usage to nodes, because areas and lines also can fit and will not be a problem. Btw. a cave_entrance, stone or volcano clearly aren't one-dimensional objects if you do a detailed mapping --Dieterdreist (talk) 08:52, 18 September 2014 (UTC)