In 1958 considerable injury occurred to trees growing in Manitoba and Saskatchewan as a result of unusual weather conditions which prevailed between October 1957 and June 1958. Unreasonably warm temperatures and strong winds during the winter months caused winter drying of conifers. A severe frost in late April, which had been preceded by temperatures of above 80°F, and lighter frosts that occurred periodically throughout May and June, caused extensive injury to buds and foliage of both coniferous and deciduous trees