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Poa sect. Poa subsect. Nivicolae (Prob.) Tzvelev was circumscribed to include four species of the Soviet Union: Poa shumushuensis, Poa caucasica, Poa irkutica, and Poa veresczaginii. Bayesian phylogenetic analyses of plastid and nuclear-ribosomal DNA revealed that it is polyphyletic, none of these species are closely related. Poa shumushuensis, type of sect. Nivicolae, or its ancestor, likely displayed the nrDNA genotype characteristic of the higher polyploid P. sect. Malacanthae. Genotype codes are designated for each species: HX, CC, PHP, and SHP. Poa sect. Nivicolae s.s. is restricted to P. shumushuensis; P. sect. Irkuticae is restricted to P. irkutica; P. caucasica is moved to P. subg. & sect. Caucasicae nov.; and P. sect. Dschungaricae is resurrected for P. veresczaginii and two other species. Although diclinous breeding systems are known in many western hemisphere species of Poa, dicliny is infrequent and little studied in Asian Poa. Poa shumushuensis is judged to be either sequentially gynomonoecious or gynodioecious. A ratio of 2 perfect-, to 2 mixed-, to 1 pistillate-flowered inflorescences from different plants in P. shumushuensis is suggestive of a recessive allele for stamen suppression, and this is associated with subtle sexual-dimorphism. Poa irkutica is diclinous with a breeding system between simple gynomonoecy and sequential gynomonoecy; P. caucasica is perfectly flowered; and P. veresczaginii has infrequent abortive anthers, indicative of limited dicliny, or sterility for other reasons possibly related to its reticulate origin. In total, 23 Asian species are here reported to be diclinous and their breeding systems are characterized. A lectotype is designated for P. fauriei.

In addition to chromosome information published in the book entitled "Caryology of the flora of Sakhalin and the Ku rile Islands" (Probatova et al. 2007) and later-in Additions (1) (Probatova et al. 2009), somatic chromosome counts were made for 33 vascular plant species (26 genera, 11 families) from Sakhalin, Moneron and the Kuril Islands. Chromosome counts were performed by E.G. Rudyka, on squashed preparations of root tips fixed with Carnoy's solution. These root tips were taken from seedlings grown from seeds ob tained in herbarium specimens, which were collected in the field by V.Y. Barkalov. Preparations were stained with iron he ma toxylin. Voucher specimens are preserved in the Herbarium VLA, Vladivostok. The plants were identified by Barkalov. The paper, including annotations, as well as English translation, was prepared by N.S. Probatova. First counts are indicated with an asterisk (*), introduced (alien) species-with (+). The plant names and geographical distribution of the species stu died are given below according to the "Vascular Plants of the Soviet Far East" (Kharkevich 19851996), S.K. Cherepanov (2007), and "Flora of the Russian Far East. Addenda et corrigenda ..." (Ko zhev nikov & Probatova 2006).

The Deschampsia cespitosa complex in Russia is revised. Related taxa common to Russia and adjacent regions (i.e. northern Europe, Arctic America and Japan) are also considered. Deschampsia cespitosa s.l. is characterized by open to less commonly rather contracted panicles, spikelets (1) 2 (3)‐flowered, 4‐toothed lemmas with the lateral teeth larger, and awns straight or bent, inserted from the base to the top of the lemmas. Due to extensive overlapping in diagnostic characters, it is not possible to accept the specific status for D. borealis (Traut.) Roshev., D. brevifolia R.Br., D. macrothyrsa Tatew. et Ohwi and D. obensis Roshev; instead, they are treated as subspecies of D. cespitosa (L.) Beauv. Morphological differences are insufficient for a clear differentiation among subspecies, and geographical distributions also need to be considered. A total of 14 subspecies is accepted. Observations on ecology, problems of specific and subspecific delimitation, a distribution map, and considerations of evolution of the complex are provided. One new combination is made, Deschampsia cespitosa ssp. sukatschewii (Popl.) Chiapella & Prob. © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society, 2003, 142, 213–228.