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.

210 A phenological atlas of plants folded and bundled, but gradually getting separated on their stalks. Leaf expansion is observed when small leaves have appeared, but leaf blades are still heavily corrugated and not yet fully unfolded. In conifers, needles on shoots become separated from tight bundles. 3. LEAF-OUT (FULL LEAF) International phase code BBCH 12-13 (Growing stage.., 2001; Meier et a l, 2009) Phase description First leaves can be considered fully developed when their blades have unfolded and reached a normal size typical of a given species. A species is considered to be in the leaf-out phase when some 10% of specimens already have full-size leaves. Expansion of a majority of leaves to full size is considered to complete this development phase. Further info Fenolog .rgo.ru: ‘Leaf-out’, appearance offully unfolded leaves - small, quite separate leaves with clearly visible stalks have appeared; leaf blades have smoothed out from corrugated to slightly wavy. Growth of young shoots - young growing green shoots have become visible, with leaves gradually expanding on them in the process. Onset of summer vegetative development -leave s have become nearly fully unfolded and smoothed, enlarged to normal size, with deeper green chroma, and harder texture. Terentjeva £ Yu. (2008): Young le a f- a leaf has reached its normal size, but is still of vernal bright green color, soft, tender. Summer vegetative de velopment - leaf of normal size and typical summertime dark green color. Sinel’nikova N. V. and Pakhomov M. N. (2015): Leaf-out is interpreted as the appearance of fully unfolded leaves, leaf blades turning from corrugat ed to wavy, gaining size and shape typical of a given species. In coniferous plants needles have expanded to full size and their growth stops. In winter annual dwarf shrubs (cowberry, crowberry, dwarf Labrador tea, cranberry) leaf-out is observed on annual shoots. Sinel’nikova N. V. and Pakhomov M. N. also distinguish between sub-phases: onset of annual shoot growth, end of growth, and lignification, which we don't use in our observations.