In reply to: Thomas54 "In the leave no trace training course I had with Boy Scouts the trainer extrapolated the highly sensitive areas of the desert southwest or the delicate mountain alpine regions with your neighborhood forest. The general training was a scare tactic that if you take a step off the trail the entire ecosystem will fail."
Not a scare tactic...The entire ecosystem won't "fail", but can be significantly damaged. Cryptobiotic soil crusts, consisting of soil cyanobacteria, lichens and mosses, play an important ecological role. In the cold deserts of Utah, Arizona, Colorado, and New Mexico, these crusts are extraordinarily well-developed, often representing over 70 percent of the living ground cover. Cryptobiotic crusts increase the stability of otherwise easily eroded soils, increase water infiltration in regions that receive little precipitation, and increase fertility in soils often limited in essential nutrients such as nitrogen and carbon.
Just saying...they are pretty darn important and should be protected from disturbance such as trampling by hooves or feet, or driving of off-road vehicles.
Hence the LNT messages provided at your training....