Krummholz island plant species density data for East of Tvan, 2000.

Species richness (density) on one meter sq. plots were measured on windward and leeward sides of krummholz trees previously studied by Seastedt and colleagues. Species richness of adjacent dry meadow tundra areas was also sampled. The results indicate that species richness is initially increased by the passage of tree islands. Richness was higher in leeward areas than on either windward or open tundra sites. The hypothesis that successional species must tolerate low nitrogen conditions found in the windward sites of tree islands was not supported by findings obtained here.