You all can look at history: between 1860 and 1920 about 87% of New Hampshire forest was for the most part mowed down (God bless ole John Henry!) and the rivers were polluted (one good thing Nixon did with the
clean water act of 1972 http://www2.epa.gov/laws-regulations/summary-clean-water-act). So, the forest we see around us is not the original primary forest (primarily softwoods) but impacted into the man induced secondary forest (mixed hard and soft woods- making the birch and maple the iconic New England trees). Hail, hail, the gifts of the Industrial Revolution. So, yes, as climbers, we should be more respectful/mindful of the micro-ecology of cliffs. Their must be an expert among us who can speak to what real impact that cleaning of cracks, scrubbing of lichens, and the disruption and annihilation of critters tiny and not so tiny has on New Hampshire's cliffs. As a climber who has done his share of un-earthing new routes, it has been my observation that if the routes do not get climbed it does not take long for mother nature to fill in the cracks and reestablish plants and critters. Most of the original equipment returns. The real question, however, is what rare and fragile plants and animals get annihilated and never come back and become local extirpated or made outright extinct? also, even things grow back, is it the original stuff?
I have been a major part of establishing routes on what have become high use areas. In particular I refer to Echo Crag, Mt. Oscar, and the Beer Walls over in the Adirondacks. I have always been disturbed and alarmed at how the base of these areas ecology have been majorly impacted. When I first walked into the base of Echo Crag back in 1992 for the most part the base of the cliffs were a field of Trilliums. Now they only remain in isolated clumps. The foot traffic has been so great that trail work has been needed to prevent trail erosion. Has anyone noticed the markers at Oscar measuring, over time, the extent of the reduction of soil from climber traffic. I believe their has been a post here about that- Ward Smith I believe has been involved with this project. (who can speak to this?) I know that the base of my climb Live Free or Die (5.9++??) at the Beer Walls is about three feet longer than when I first climbed it in 1982 with Rich Leswing.
Putting up routes in particular, and the climbers who follow, because they became popular climbs and/or areas, is really a self serving act. It is ego driven. Nature has no say in the matter as to our handy work. Do we give up climbing and recreation? Probably not. Can we better educate, manage, and self regulate our selves as a climbing community? You betcha we can. John Henry's drive for timber and profits is what helped drive the creation of NH and national conservation groups, our NH State Parks, and the White Mountain National Forest. We cannot undo our acts of the past, but we can become great advocates and stewards of our land and crags into the future.
Any grad students out there want to take this on: the environmental impact of climbers on NH crags?