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I'm using ArcMap 10.3 and am looking for some guidance on how to "connect" two layers. Layer one contains non-overlapping polygons (site) Layer two contains overlapping polygons (species) I would like the attributes from layer two to appear in the layer one polygons when the fall within a polygon.

This will create a list of species within a site.

  • It would be best to do this from a personal or file geodatabase feature class to keep the OIDs static. Use one of the overlay tools (Intersect, Identity, Union) to join the tables which will create overlapping polygons with each species then join the overlay by attributes to the site polygons by OID, select each species and calculate the field with an append to the species present field (Site.Species_Present = !Site.Species_Present! + !Species!).. this will compile the species into one field regardless of how small the overlap; what are you trying to achieve with this? – Michael Stimson Apr 27 '17 at 21:46
  • Thanks Michael, this is great. I need to work out how to do some of this but think i get the concept. We are trying to create species lists for land parcels to help prioritize conservation action. Really excited to see if we can make this work. – James Apr 27 '17 at 23:43
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    May I suggest you trim the very small overlaps.. species don't respect property boundaries but sometimes the overlap is less than a few percent of the site. If you do this in a geodatabase the shape_area will be calculated for the overlap and the site (as well as species) area should exist in the table; you can calculate percent overlap and remove very small anomalies before it has a chance to skew your data in further analysis. – Michael Stimson Apr 27 '17 at 23:49
  • Sorry what do you mean by "Use one of the overlay tools (Intersect, Identity, Union) to join the tables which will create overlapping polygons with each species"? the layer I have already has all the overlapping species polygons. Sorry I'm missing something here - really appreciate your help. and great idea re removing the small overlaps – James Apr 28 '17 at 0:03
  • Intersect resources.arcgis.com/en/help/main/10.2/index.html#//… Identity resources.arcgis.com/en/help/main/10.2/index.html#/Identity/… union resources.arcgis.com/en/help/main/10.2/index.html#/Union/… I think the best for your purposes is intersect which will allow you to intersect your sites and species (limit 2 layers with basic and standard license) to find your common areas. – Michael Stimson Apr 28 '17 at 0:06

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