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In QGIS 2.18 I draw polygons on a certain grassland-type on aereal imagery. Sometimes, there are other landcover-types within the patches of interest, so I'd like to draw polygons with holes.

In the example, I want to exclude the small forest-patches within the grassland. Is there any procedure other than creating a new layer for everything I want to exclude and then clip my grassland-layer?

enter image description here

PolyGeo
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yenats
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1 Answers1

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Use the Advanced digitising Add ring tool

Turn on the Advanced Digitising Toolbar in View > Toolbars > Advanced digitsing, or Edit > Add ring

Then with the layer editable, click on the Add ring icon

enter image description here

and click away around the woodland, right-click to finish

If you then want to add a polygon to fill the hole, then use the Add feature in the normal way, but with Settings > Snapping Options set up so you can snap to the nodes of your ring so you don't end up with overlaps or gaps.

Martin Hügi
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  • Just realised this had been asked before here https://gis.stackexchange.com/questions/29280/how-to-create-a-hole-in-a-polygon-in-qgis so I expect this may get closed as a duplicate. I should have checked first. – Martin Hügi Aug 09 '17 at 17:45
  • The link leads exactly to this question - and I didn't find the same question here. – yenats Aug 09 '17 at 17:49
  • Sorry copied wrong link, have now edited my comment – Martin Hügi Aug 09 '17 at 17:50