Will the US government decide to euthanize excess wild horses?

This a very fine market, bayoubear.
Having lived near BLM land in SW Nevada (Death Valley Area), I can attest to two things.
1) The wild horses are a wonder to watch. Stampedes across the valley floor are very common, and so delightful to the nearby residents or anyone who happens to pass when they do.
2) The area where they roam simply does not have enough vegetation to support the growing herds. I have seen some wild horses emasculated and some dead on the side of the road.

A very sad state of affairs. You see, man-kind created the towns and highways, that trapped these herds in an area that gets extremely dry during the summer. Before we did this, the herds would travel south to the Colorado River area for the summer. They can no longer do this primarily because of I-15 between Los Angeles and Las Vegas. Eerily, Vegas means 'wild horses', and Angeles means 'angels'.

This will be interesting to follow. I was involved in the first BLM wild horse roundup back in the mid 70s, and the plan all along was of course to capture and adopt out any excess animals. There have been successes and abuses along the way among adopters, but it seemed to work for quite a while. Nonetheless, one has to consider that these animals are non-native to the desert / high-desert environments they range in, and between horses and burros they consume forage and water that the native wildlife desperately needs (deer, bighorn sheep, etc.). Most ranchers out there hate the darn things; people from the city think they're a natural part of the landscape and should stay. From a biologist's viewpoint, BLM would be doing the right thing to humanely remove animals the land can't support, BUT the hue and cry from animal rights folk is going to be huge. They will most likely stop any plans to kill the horses... but I could be wrong.

According to this story, the BLM report on the issue is due out on Sep 22.
http://www.tucsoncitizen.com/daily/opinion/94940.php

If there is no clear news that BLM will start euthanizing at this date, the question will settle as NO.