Макарова, О. А. Фенологический атлас растений / Н. В. Поликарпова, О. А. Макарова ; М-во природ. ресурсов и экологии Рос. Федерации, Федер. гос. бюджет. учреждение «Гос. природ. заповедник «Пасвик» ; [худож.: Хохлов В. А. ; пер.: Кислова О. С.]. - Рязань : Голос губернии, 2016.

196 A phenological atlas of plants ing spring and summer, as well as the wintering environment. Besides, the timing of autumn events in trees and shrubs is much dependent on their age, type of soil, distance to groundwater, and location. T he beginning of leaf coloration is timed to the day when the first autumn-color leaves (needles) or entire branches (strands) were seen. The process of leaf color change (to red, yellow, orange, brown, etc.) gains pace slowly. The first autumn leaves usually appear in the mid- or lower crown. Soon after that, a birch tree would have entire branches with autumn-colored leaves visible from afar (‘flags’). Autumn phases in pine and spruce are less conspicuous, since only part of the foliage gets discolored: on 2-3-year-old branches in pine, on 5-7-year-old branches in spruce. Needle coloration in pine begins in the second half of August on lower parts of branches. In spruce this phase begins later, most often in October. In many trees and shrubs leaf fall begins soon after the onset of leaf coloration, and also proceeds very gradually and at first inconspicuously. In some species however leaf fall usually begins only after most of the foliage had changed color. Among small-leaved species, the beginning of leaf fall is more distinct in aspen and some willows. Our programme includes observations of leaf fall onset for only several species, in which this phase is the most distinct. The day when the first autumn-colored leaves (needles) begin to fall is defined as the beginning of leaf fall. In pine this phase can be identified by slightly shaking branches. Altitudinal zonation in the mountains is visible from a distance during autumn