Effects of Ant Mounds on Soil Chemistry and Vegetation Patterns in a Colorado Montane Meadow

Abstract

The vegetation and soil chemistry of 15 abandoned mounds of Formica canadensis were compared to control quadrats in a meadow at 2900 m near Gothic, Colorado, USA. Principal Components Analysis indicated the mound vegetation was relatively homogeneous and distinct from nonmound vegetation. Discriminant Analysis indicated that mounds were characterized by Bromus polyanthus and Achillea millefolium, and nonmounds by Poa interior. A parallel analysis of 15 soil chemicals indicated some statistically significant chemical differences between mounds and nonmounds. Several micronutrients (Fe, Zn, Mn), were lower in mounds but were unlikely to be deficient. Ant—dispersed plants (myrmecochores) were almost entirely restricted to nonmound quadrats.