Rapid use of resources as a basis of the Heracleum sosnowskyi invasive syndrome.

The functional properties of the invasive Heracleum sosnowskyi were compared with those of the native Heracleum sibiricum. The leaf and root traits, as well as those of a whole plant and of the mycorrhiza formation, were studied. H. sosnowskyi can fulfill the high-productivity potential only under the optimum availability of resources (especially water), while it is poorly adapted to maintain a high physiological activity under the unfavorable soil conditions. An important component of the H. sosnowskyi invasiveness is an ability to utilize rapidly resources in both the above- and underground areas at the optimum conditions.