Morphological Variation in the Seed of Betula populifolia Marsh: Since plants grown in metalliferous soils often express growth abnormalities (Gardea-Torresdey et al., 2004), we questioned whether varieties of B. populifolia colonizing environments contaminated with metals exhibit modification in seed morphology, (SA) especially seed size and weight. Hence, the purpose of this study was to determine if seed from metal contaminated soil exhibited morphological differences that correlated to total soil metal load (TML) and if so, could these differences theoretically impact dispersal effectiveness. Seed size at each site varied by as much as 220% and was normally distributed with far greater numbers in the mid-size classes. Tukey analysis (1) indicates that two sets of data (sites 41 and 18, 14 and 14-16) produced seeds of statistically similar size. A two-tailed t-test between the sites above and below a TML of 3.0 was significant (F=.76, p<.001), indicting that seed size at sites 14 and 14-16 were significantly smaller than the rest of the samples. Separation of data into subsets of sites above and below the soil metal tolerance threshold value of 3.0 indicate a weak but significant relationship (F=0.26, p>0.001). Wing loading (3) rates of seeds below the TML threshold of 3 (sites 14 & 14-16) were significantly lighter and smaller than those above 3 (F=.11, p< .01) However, the relationship (9) between the mean wing loading rates and TML. The polynomial regression is not statistically significant (r2 =.15, p = 0.55).