On 08/11/2019 20:50, Philip Barnes wrote:
No problem with boats and greenhouses that don't move. But these are probably seasonal and certainly shouldn't be mapped from aerial imagery alone as they may have long gone. They certainly need a recent survey.
I don't think polytunnels in open fields should be mapped, for this reason. They are seasonal and transient. They will be there for part of the year, and then removed after the growing season, and may not be used again on the same field the following year.
However, there are some permanent polytunnels that are, effectively, plastic greenhouses. Those can, and should, be mapped. But it needs local knowledge to map them. You can't do it from imagery.
It reminds me of the time an armchair mapper carefully traced a Maize Maze that had existed for a short time in a field near me a couple of years earlier.
I'm pleased to see that we do have the Hampton Court Maze mapped, though :-) Mark _______________________________________________ Talk-GB mailing list Talk-GB@openstreetmap.org https://lists.openstreetmap.org/listinfo/talk-gb
