montane A montane condition is an environmental condition in which an altitude range falls between mid-altitude forests and the tree line. LTER:350 ORCID:0000-0002-4366-3088 The exact level of the tree line varies with local climate, but typically the tree line is found where mean monthly soil temperatures never exceed 10.0 degrees C and the mean annual soil temperatures are around 6.7 degrees C. In the tropics, this region is typified by montane rain forest (above 3,000 ft) while at higher latitudes coniferous forests often dominate. altitudinal condition