The relationship between landforms and vegetation was examined to clarify the long-term effects of geomorphic processes on vegetation structures on mountain slopes. This study was conducted in the Genbunzawa and Zenroku-zawa watersheds in the upper Azusa River basin, central Japan, where landslides and sagging landforms prevail. In the middle and lower parts of the watersheds, landslides characterized the vegetation structures. Larch (Larix kaempferi) forests occupied the scarp slopes of large landslides, while spruce (Picea jezoensis var. hondoensis) forests occurred mainly on landslide deposits. Even-aged alder (Alnus inokumae) forests and mature fir (Abies homolepis) forests dominated the alluvial cones that form in the lowest part of the watersheds. However, spruce and fir-spruce forests were found on a large debris-flow lobe (LDL) in the alluvial cone in the Genbun-zawa watershed. The LDL seems to have controlled the distribution of debris-flow paths on the alluvial cone because both recent debris-flow paths and even-aged alder forests caused by debris-flow disturbance were restricted to the area south of the LDL. Dendrochronology and radiocarbon dating results suggest that a large landslide occurred in the middle of the Genbun-zawa watershed ca. 370–350 years ago and had lasting influences on the vegetation by creating new edaphic conditions on debris-flow lobes and by changing the local disturbance regime in the alluvial cone.

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Artemisia spp. (mugwort) are herbs with significant use in the traditional folk medicine. They are widely used to treat various symptoms of respiratory, digestive, infectious, and gynecological diseases. Recently, their efficacy has been verified through the pharmacological analysis. However, only limited evidence is available regarding their prehistoric importance as medicinal herbs, and even the largest archaeobotanical database of West Asia, the Archaeobotanical Database of Eastern Mediterranean and Near Eastern Sites (ADEMNES), has only one record of Artemisia utilization. It is remarkable, then, that recent excavations at three prehistoric sites in the Middle Kura Valley of West Azerbaijan, South Caucasus, have yielded substantial amounts of Artemisia seeds. Further, evidence from one of these sites, Göytepe, suggests that Artemisia was used as an insecticide/fungicide. The high frequency of occurrence of charred Artemisia seeds in the three sites implies that this plant was used in daily life, and its exploitation may be considered one of the cultural components of prehistoric West Azerbaijan.

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The Kuwagaishimo site is a large-scale settlement site of the late Jomon period (ca. 2000 cal BC) in the Kansai region with many stone axes that were probably used for gathering or managing such plants as rhizomatous ones and beans. This site is considered as a transitional site where the plant management using stone axes of central Japan changed to that in western Japan during the middle to the late Jomon periods (2500 to 1500 cal BC). Study of seed or fruit impressions on potsherds from this site revealed an impression of a Vigna seed that was as large as modern domesticated azuki varieties on a potsherd of the late Jomon period.

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