# Spatial analysis? Two layers?

One is LandPlot and the other is Soils.

When I open the LandPlot attribute table I see I have 500 specific plots of land. When I open the Soils attribute table I see I have 5 types of soils (let's call them TypeA through TypeD). The issue is I want to select the specific Landplots (not all 500!) that contain TypeA AND TypeC soils (they can contain other soils in the plot but must include at least those two soils). I can't determine the proper process though.

I thank you for any advice.

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What format are each of your files in, vector or raster? –  Boyle300 Apr 12 '12 at 20:14
I'm not exactly sure.... My soils seem very pixelated so I'll say raster? My LandPlot polygons are definitely vector though. –  CaliforniaGirl Apr 12 '12 at 21:14

As I don't have the rep to comment I'll answer as an extension of Jersey Andy.

Assuming a vector(probably polygon) layer.

Firstly, select the soil types:

• Select by attributes.
• Layer: The layer with your soil types.
• Method: Create new selection
• Select as: SOILTYPE = 'TypeA' AND SOILTYPE = 'TypeC'

The key is to use the AND. I suspect what you've done is used an OR.

You can now either export the selected to a new layer (probably sensible in this case as you're still learning) or go straight to stage 2 being sure not to deselect anything:

• Select by Location
• Select features from
• tick the LandPlots layer
• Source layer
• Either:
• The one you exported.
• OR:
• SoilTypes (this assumes...)
• make sure you tick: _Use Selected Features_
• Spatial selection: Your choice, but usually it's the top one.

This will then do a spatial intersect and the land-plots selected will intersect with the ones of a certain soil type.

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selecting by attributes using SOILTYPE = 'TypeA' AND SOILTYPE = 'TypeC' would result in an empty selection set, because there are no records for which that entire statement is true. I'll amend my answer below. –  Jersey Andy Jun 20 '14 at 20:10

Let's assume it's polygon data, not raster. If so, you need to do two overlay selections, where the second one is only operating on the polygons selected in the first one. First operation: select soils where type = TypeA and then select landplots that intersect those soils. Second operation: select soils where type = TypeC and then select from within the selected landplots for those that intersect those soils.

In ArcGIS, this would be a sequence of "Select by attribute" and "select by location" operations.

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Hi, thank you for your suggestion.I just tried this but I think something went wrong. I'm still getting individual Landplots that do not include 'both' of my soil types. When I did 'select by location' (after select by attribute) I did "select features from Soils and then Source Layer: Landplot and then Spatial Selection Method: Target layers features intersect the source layer feature. I then took the NEW layer and repeated but with the other soil type. Still this did not eliminate any plots in my LandPlot layer. It also shows soil that stretches way out of the individual plots. Using Arc10. –  CaliforniaGirl Apr 12 '12 at 21:47
any tips por favor? –  CaliforniaGirl Apr 12 '12 at 22:23
Sorry, I didn't see this until now. You probably don't still need to know, but for reference, this is what I meant, using the 10.2 interface, prompts have changed a bit. 1. Select soils where type = TypeA. 2. Select by location, selection method = "select features from: landplots, source layer: soils, spatial selection method: intersect..." 3. select soils where type = TypeC. 4. Select by location, selection method = "select from the currently selected features in", target layer: landplots, same source and spatial method. Result should be landplots that touch both soil types. –  Jersey Andy Jun 20 '14 at 20:11
I think what was wrong when you did it before was that in the second "select by location" you need to make the selection method different, "select from the currently selected features." –  Jersey Andy Jun 20 '14 at 20:18