There were birch trees on the top of the hill but they were very small. Their trunks were quite thick but lacking in height and it could be seen that the topmost branches had been frozen off. The leaves looked like those that sprout from branches that have been burnt in forest fires. I was told that they produce very little sap each year and that consequently their wood is harder than is usual – also, that the trees were fairly old. The farther north I went, the shorter they became.