On Sun, 18 Aug 2019 at 07:40, Joseph Eisenberg <joseph.eisenb...@gmail.com> wrote:
> > But I see that there is some desire for a tag for generic cropland, or > farmland used to grow unspecified crops. For this I would suggest the > key "farmland=cropland" or "crop=field_cropland", rather than crop=yes > (less specific) or produce=crop (unclear). > Before we get to the details of how we're going to tag it, we need to be clear on what "it" is. Modern agricultural techniques (mainly the use of fertilizers, whether natural or artificial) permit monoculture, where a single type of crop is grown in the same field, year after year. This we can map with crop=* (or crop=yes or whatever replaces it when we know a monoculture crop is grown but we don't know what it is, although that seems unlikely). However, it is still fairly common to use crop rotation where different crops are grown in different years, or even two different crops in the same year. See https://en.wikipedia.org/wiki/Crop_rotation One crop in the rotation may be grass, harvested for silage to later be fed to animals. In some cases a field in a crop rotation may be used as pasture for a year to directly feed animals. Land in crop rotation may be left fallow for a year, with no crop. OTOH, where the land is very uneven then it might be used for nothing but pasture (sheep or goats are the usual "crop" on land like that). Maybe we need crop=rotation rather than crop=yes. I suspect we need both. Not necessarily as the tag crop=yes if everyone thinks there's a better tag, but we need to cover "this is used to grow crops in some sort of rotation" and "this is used to grow crops but I can't figure out what type from this distance and I don't know if it's monoculture or rotation." Or maybe we should restrict ourself to mapping it as farmland because, in general, we don't know what a farmer is going to do with a given field from year to year. There are specific cases where we're fairly sure a field is used for monoculture and we have specific tags for those: orchard, vineyard, etc. But, in general, just because I see oilseed rape in a field this year that doesn't mean it's going to be oilseed rape next year (it usually isn't, around here). I should also point out that many farms around here devote some or all of their land to tourism. Is that crop=tourist? Where the tourists pitch their tents or park their caravans is a camp site, but some of the farmland may be left for tourists to use recreationally (aka the farmer having given up on farming completely because it's no longer economic). -- Paul
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