Hi Toby...very interesting question...here is what I would do:
Draw the map with the peachy colored area as one texture with no state boundaries. Then I'd show the orangy colored area as another texture with no state boundaries. I would include the state boundaries for the yellow areas with the state abbreviation labels in each state and abbreviate the Nebraska Territory (nt), Indian Territory (it), and New Mexico Territory (nm) as nt, it, and nm on the map. I would also put a light texture for the water and include it in the key. So the key would look something like this:
,'Key:
**** Slaveholding areas affected by ... Proclamation (States included in this area MO, TN, KY, WV, MD)
^^^^ Slaveholding areas not affected by ... Proclamation (States included in this area TX, AR, LA, MS, AL, GA, FL, SC, NC, VA)
#### Water
it Indian Territory
nm New Mexico Territory
nt Nebraska,'
Draw the map with the yellow areas labeled with state boundaries, the orange area one texture (no state boundaries), the peach area another texture (no state boundaries) and then a light texture for the water. You cannot of course label the bodies of water because those labels are not shown in print.
Done this way, you are communicating which states are included in each area. I don't know what the surrounding text is for this map but I would imagine the concept being taught is which states were affected by the Emancipation Proclamation. The exercise is NOT to teach state identification or location or relation to one another. There are plenty of other opportunities for them to learn state location in a social studies book.
Diane