To examine the relationship between frost damages in tea plants (Camellia sinensis L.) and undulations in topography, frost damage occurred on 9 May 1988 in Nara prefecture was investigated in detail. Two sites were chosen for this study: Higasa-cho tea garden, Nara city and Enga tea garden, Tsukigase village. At the frost night the minimum air temperatures were 4.0℃ (Nara) and 1.0℃ (Hari) and new buds with two to four leaves were damaged. Since the damage occurred late in spring, differences in the degree of damage among tea varieties were not seen. The damages were severer at relatively lower places at the sites. The orientations of damaged side of tea rows indicated that the damages could not be attributed to rapid thawing of frozen leaves by sunshine. The damage orientations of rows across the contour seemed to have been affected by the larger scale cold air drainage (mountain breeze). On the other hand the damages on the rows along the contour occurred on the lower sides and they are considered to have been affected not by the large scale cold air drainage but by the smaller scale downslope air motions induced by the undulations in the garden.
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