To examine if the intensive selection of Quercus gilva for hoes and spades during the Yayoi to Kofun periods found in the Kanto district also existed in western Japan, preserved preparations of Quercus subgen. Cyclobalanopsis were re-identified at 14 sites that yielded ample wooden artifacts of these periods. Re-identification showed that, at most sites within its present distribution range, Q. gilva accounted for 40–80% of hoes and spades including unfinished ones and split materials and that other species of Q. subgen. Cyclobalanopsis accounted for the remaining hoes and spades. Outside the present distribution range of Q. gilva, other species of Q.subgen. Cyclobalanopsis were selected for hoes and spades at two sites, except for one site in the Sanin district. Occurrence of Q. gilva not only as hoes and spades but as plant macrofossils in the Sanin district during these periods seemed to show past extension of its distribution to this district. The intensive selection of Q. gilva for hoes and spades seemed to have been established in northern Kyushu, judging from the present distribution Q. gilva and species of Q. sect. Aegilops in China and Korea and the route of introduction of the rice agriculture.

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Sarufutsugawa mires in northernmost Hokkaido provide habitats for boreal wetland plants, such as Carex livida. To clarify developmental processes of mire vegetation since ca. 9200 cal BP, we took drilling core samples from the Asajino-nishi Picea glehnii forest at 5.8 m a.s.l. in the lower reach of the Sarufutsu river and the Sarufutsugawa-naka mire at 11.8 m a.s.l. in the middle reach. We did additional AMS14C dating of plant macrofossils and reinvestigated Carex achene fossils from the Sarufutsugawa-maruyama mire at 15.6 m a.s.l. Caused by a drop of the sea level during ca. 6320–5290 cal BP, mires began to develop in this area after the burial of an estuary with brackish-water plant assemblages. Then vegetation of the three mires changed from wetland with submerged plant assemblages to wetland Alnus japonica scrubs. Finally, the Sarufutsugawa-naka and Sarufutsugawamaruyama mires became ombrotrophic, and Picea glehnii forests developed in the lower reach. This hydrosere was caused by a rise of the minerotrophic peatland surface above the flood level of nearby rivers with accumulation of peat, finally promoting ombrotrophy. In the Sarufutsugawa-maruyama mire, frequent silt layers in the sediments indicated that more frequent and prolonged floods than in lower reaches caused a delay in vegetation change to Alnus scrubs and ombrotrophic mire vegetation. Carex livida assemblages in this mire were established with the development of ombrotrophic mires since 1100 cal BP.

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Vegetation history was reconstructed from phytolith assemblages and macro-charcoal from sediments in the Ooshiburi-dorine on northern Akiyoshi-dai Plateau, Yamaguchi Pref., Japan. Eleven phytolith morphotypes were identified from samples, and phytolith zones were divided into zones I and II. Phytolith assemblages and charcoal concentrations in the sediments indicate that arboreal vegetation existed with abundant Sasa on the forest floor at study sites in zones I and II corresponding to the period of the last 200–300 years and that Miscanthus and Bambsoideae grassland was developed under the influence of human disturbance such as fire.

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Paleovegetation and palaeotemperature at 1160 m a.s.l. at the southeastern foot of Mt. Yatsugatake were reconstructed based on plant macrofossil assemblages from fluvial deposits in two horizons a sand layer intercalating the Blue Glass tephra deposited around MIS7.3 of the late Middle Pleistocene. A deciduous broadleaved forest grew near the study site, and a pinaceous conifer forest spread in upstream areas at higher altitudes. Plant macrofossil assemblages included taxa distributed mainly in the warm-temperate zone, such as Selaginella remotifolia, Buxus microphylla, and Phytolacca japonica. The annual mean temperature at the site of fossil deposition was estimated to be slightly warmer than that at the present (7.8°C) from the coldest limit of distribution ranges of Phytolacca japonica (8.5°C) and Selaginella remotifolia (8.1°C).

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