The larger trees also create microclimates within the forest. Forest canopies allow for less fluctuation in temperature and provide some protection from frost. They obstruct sunlight during the day and have an insulating effect at night. Winds have been known to blow down trees on the mountain. Burnaby Mountain is blanketed with a second-growth forest that hosts a number of species.
Ferns are a common sight in the woods.
Their life cycles include both gametophyte and sporophyte stages. Sword ferns are very common, especially on the higher north slopes and in areas of reduced canopy cover. They are the largest ferns. Wood ferns are a smaller species. These are generally less common although their numbers are noticeably higher on the western slopes.