Effects of environmental conditions on the distribution of resources between generative and vegetative reproduction were considered in relation to several theories. Our objective was to study the effects of heavy pollution-induced habitat deterioration on the growth and reproduction of Betula pendula Roth trees. The length of vegetative short shoots of the birch, the chlorophyll concentration in leaves, and the reproductive effort were studied for the most polluted site – a zinc-lead dump in Wełnowiec (the district of the city of Katowice) and the control site in the village of Smoleń near the town of Pilica. All the plant samples were collected from 10 microhabitats categorized on the basis of different levels of heavy metal concentrations in the topsoil. The length of the vegetative short shoots was greater than that of the trees growing at the control site. The same increasing tendency was observed in chlorophyll concentrations. The somatic cost of reproduction in Betula pendula was higher for the polluted site, presumably owing to both more intensive generative reproduction and resource limitations in the unfavorable environments.