Create a Choropleth Map

In your layers panel, hide (uncheck) everything except your vanHoodsCount and vanShoreline layers.

Right-click on the vanHoodsCount layer and select Properties.

On the new window, select the Symbology tab.

At the very top, there is a button where Single Symbol is selected.

Click on that button and select Graduated. This will allow you to display graduated colours representing classes of attribute values.

On Value select: DougFirs
On Precision select: 0
Check the box for Trim
Color Ramp: pick a color ramp that looks like it would represent the prevalence of Douglas Firs.
On Mode select: Natural Breaks (Jenks)
On Classes select: 5
Click Apply and drag/resize your symbology window so you can see your map canvas. When you are satisfied, click OK and close the window.

Your map should look like this:

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