Usage of plants for weather and climate forecasting in Bulgarian folk traditions

Observations of plants are a common source of information for predicting weather patterns. In this study of Bulgarian folk knowledge, more than 30 plant species were documented as weather indicators, 20 of which were assessed as having a very high level of repeatability. Three species of fungi are also reported as weather indicators. The plants, consisting of herbs (47.6%), trees (28.6%) and shrubs (23.8%), are well known and widespread in the study area. The original texts relating to traditional forecasts and the involvement of plants in folk beliefs and customs are presented. Folk botanical knowledge about the morphology of plants and phenological states (e.g., grass growing, fruitfulness of trees, natural leaf fall, secondary flowering) are the basis used by Bulgarians for mostly long-term forecasts, and for predicting seasonal disasters caused by rain, drought, snow, extreme heat or cold, ice, or wind. The knowledge of folk meteorology today and its rational basis and importance are discussed in a contemporary context.