I think the actual use is about the same however the horse use in the Sierra is more concentrated in specific areas and in the Wind Rivers, it seems to be evenly spread out. The impact in the Sierra seems worse because it is so dry in the summer. In the Wind Rivers, you get lots of afternoon storms so dust is much less a problem. Also, the warmer Sierra climate exasperates the algae problems in lakes. The hiking/horse riding season in the Winds is also shorter.

One trend I saw in the Wind Rivers is to use goats and llamas and I have not seen this in the Sierra. I think this may be regulatory- in the Sierra a goat or llama is counted as "stock" in the same manner as a horse and are more regulated.

This summer the drought has caused the water levels in lakes to be very low and nearly ALL streams in northern Yosemite are nothing but a few stagnant puddles. This makes for very warm water and lots of dust.

I really think one problem is too many horses using the same trail. There are tons of trails in Emigrant Wilderness and if you were to distribute the use more, there would be less problems.

I also think a lot of regulations are being ignored. I never see a wilderness ranger or game warden. I think our regulatory agencies are really being choked for funds. I think the "100 feet from water" rule used for backpackers needs to be extended a much farther distance for horses.