Solved. First, here is the link to the BLM online map system:
BLM Online MapChoosing your state is the easy part. If you have the same experience that I had, you pull up the map, zoom in, and you can't see much of anything, other than big mustard yellow blotches. Useless.
It turns out that the default settings on the layers on the map are virtually opaque. Here is how to fix it:
After your map loads, go to the menu in the upper right and click on the "layers" icon, which looks like a stack of paper. A big box will pop up on the right edge of the map.
Now scroll to the bottom of that map. Click the box next to "surface management." It should turn blue.
Now click on the little row of three horizontal dots next to the words "surface management." A small box pops up. One of the menu items is "transparency." Click on it.
A slider will pop up. As far as I can tell, the slider is set to "opaque" by default. Move the slider toward the right, to about the 60 percent level. That preserves some of the color overlay (which gives you the all-important info about which land is BLM and which is not), while still letting you see roads and other key landmarks.
Not the most user-friendly map I have ever seen, but it gets the job done.
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