The enclosing features are area features coming from http://overpass-api.de/ .
There is some discussion here:
http://wiki.openstreetmap.org/wiki/Overpass_API/Areas
I think a landuse=forest should create an area, but maybe it hasn't been generated yet. I used the script below to find out that areas were last generated 2 days ago. Is the feature newer than that?
This is a simple about the simplest script that will return an area:
http://overpass-turbo.eu/s/eo7
According to the results, areas were last generated 2 days ago. The timestamp is returned in the output, Overpass Turbo does the math and displays it if you hover over the statistics on the lower right.