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.

228 A phenological atlas of plants An interesting line of study is estimation of a plant's yield. This concerns both the seed yield of woody species (coniferous and small-leaved) and the fruit yield of dwarf shrubs and herbaceous plants. The procedure is to choose a plot of certain size (e.g. 5 x 5 m, 25 x 25 m, 50 x 50 m, depend ing on the aims) during the flowering stage, and count shoots of a given species within it. Several specimens are then chosen for observation, and their generative shoots are labeled with numbered tags (herbaceous plants can be marked out by tying tracing paper/cloth on thread to them). When monitoring the process of fruit formation and ripening and seed spread one should follow the chosen technique and carefully record all observations and estimates in datasheets and field log. It would be interesting to estimate the proportion of plants with fruit set in the total number of flowering plants in the plot, fruit/seed yield, total and average weight of seeds and other indices. The beginning of the academic year is the time for studying the leaf fall process in various species (birch, goat willow, rowan, aspen, alder). Observations should be carried out in a permanent sample plot sized some 100 m2, the plants labeled with numbered tags, the extent of leaf fall estimated as percentages starting with the onset of leaf fall until its end at equal time intervals (e.g. on every third day). If such observations are done annually, they w ill provide interesting local material on the rate of leaf senescence and the timing of growing season completion at specific sites. It would be desirable to supply these data with a description of the weather at the time of observations to be able to compare the different years and find explanations for distinctions (effects of wind speed, air temperature). Weather info is now available from the Internet, and some schools even have their own weather stations. Nonetheless, the observer should take notes on actual air temperature and wind speed on each sampling day on the spot. Another kind of survey is based on the technique by the Ural phenol ogist V. A. Batmanov (1952). Observations are done on specific dates irrespective of the weather, weekends and such; for instance, plant phe- nophases are recorded on September 5,10,15, 20, 25 and 30. People tend to remember their own observations better. In autumn one can also monitor and record the following: