What's clean and freshly done today in this wet moist rainy western Oregon zone will -- in just a few years ahead (1-10 years) -- often will become a renewed moss covered heap of stone virtually appearing as if it were never touched by human hand before.
So if you know various local bouldering teams that go outdoors frequently to their favorite bouldering haven to unearth various new bouldering problems -- we recommend that you set yourself into a pattern of follow that team.
As they unearth a series of boulders, whether a few stones, or a dozen stones at an entire boulder zone, make plans to visit those same bouldering zones in the next few short years just after they had progressed through that zone, because those freshly unearthed stones will still be quite clean (i.e. moss free) for only a short time thereafter.
Now is the time to retag some of those cool ascents without all the extra effort to re-clean de-moss those stone many years later.
Luckily not all boulders re-grow a moss carpet at the same rate. A lot depends on the stone characteristic nuances (surficial features) like grittiness, smoothness, and its compositional makeup (basalt, andesite, dacite, etc). Moss tends to cast new spore seeds in tiny niches of the rock surface, the the seeds sprout (after it becomes moist) in the tiny rock vesicles, usually from a high spot, then progressively down the boulder over a period of years (moss hangs ya know!).
