Distribution of seeds of the giant hogweed (Heracleum sosnowskyi Manden.) in the winter period.
The results of experiments on natural distribution of seeds of the giant hogweed (Heracleum sosnowskyi Manden.) in the winter period are presented. It was found that viable seeds are preserved on the umbrellas of this alien plant in winter. Falling of single seeds during the winter period is not much different from falling of seeds in the summer-autumn period. It was shown that seeds under the influence of various factors, in particular, under the influence of strong gusts of wind, can move up to 5 m from the mother plant. It was revealed that the seeds are also able to move together with broken umbrellas over distances many times greater than the distances of the natural scattering of single seeds. Experimental observations on the movement of umbrellas at a distance of 40 ± 9 m for 15 min suggest that the range of movement of umbrellas can be hundreds of meters on a flat surface of icy roads. The high germination of seeds left on the umbrellas allowed us to conclude that measures to control Sosnowsky's hogweed should include the destruction of dead plants with seeds until a stable snow cover is formed.