Growth of samaras of Acer negundo L. in Tyumen conditions

The data on the number of samaras in the inflorescence and their morphometric parameters in the ecological conditions of the capital of the Tyumen Oblast were analyzed. It was found that chemical pollution of the atmosphere accelerates the growth of samaras in the initial stages of ontogenesis and slows it down at the end of the period of fruit formation. The proportion of asymmetric samaras and the size differences between their left and right halves increase under pollution. Keywords: ACER NEGUNDO, VARIABILITY, ENVIRONMENTAL POLLUTION, CLIMATE, LENGTH AND WIDTH OF THE SAMARAS