Northern march of Arthedain

The plants and wildlife of Arthedain suffered only a little less in the time of Men. Overrun by glaciers in the distant past and dominated by the Iron Mountains in the last ages before the rising of the sun, northern Eriador was never blanketed by the vast, dense forests favored by the Ents. Instead, it was covered by a silvan woodland, with mixed forests in the watered areas and grass and flower covered glades on the drier hilltops and uplands. Unfortunately the first Eriadorans to move herds into the country, called by them the Northern Marches, steadily cut the woodlands and grazed sheep and cattle on the undergrowth that remained. The forests here, as in Cardolan, failed to regrow under the impact of the grazing. By the time of the founding of Arnor, the northern hills were, if not heavily settled, certainly changed. Moors and prairies were widespread, and the wooded country had retreated either to the best watered or most isolated regions. Even without forest cover, the hills of the Northern Marches could still support man and beast, if both were willing to work and could tolerate the starker beauty of grainfields, grass, and flowering heather. The telling blow to the Arthadan ecology in the mid-Third Age was the advent of cold winters—which came along with the rising power of the Witch-king. The constant strain of providing firewood out of dwindling groves was one problem. Rebuilding houses and barns for greater insulation was another, as was expanding cropland and gardens to produce more food and a greater variety of foods as insurance against the variable weather. Wild animal species were crowded out as Men took more room for their own needs. Wild plants already troubled by the short growing season lost ground to the more necessary domestic varieties. By the time of the Great Plague, Arthedain's population had dropped considerably from the days of old Arnor; the people, animals, and plants that remained were tougher then they were, more efficient in their use of available resources, and more grimly determined to hold on to their own patch of hillside.