Divergence in diversity-area relationships between lawn and non-lawn plants in residential landscapes

Abstract

Context In residential landscapes, people acknowledge and manage larger, conventionally attractive plants differently than smaller, less conspicuous ones, possibly leading to a divergence in basic ecological patterns such as diversity-area relationships. Objectives We tested for divergences between lawn and non-lawn plants, and compared perceived and actual species richness in residential yards. We hypothesized that: (1) homeowner perception of plant species richness is more related to the actual species richness of non-lawn plants than lawn plants, and (2) alpha diversity will increase more rapidly, and beta diversity will decrease less rapidly for non-lawn plants than lawn plants with increasing spatial scale. Methods We recorded all plant species in four 5 × 5 m plots in the front and back yards of 30 residences within four neighborhoods of Gainesville, Florida, United States (N = 238 plots). We also surveyed residents regarding perceived plant species richness in their yards. Results We detected 386 non-lawn and 140 lawn species. Perceived plant species richness was positively related to non-lawn species richness and negatively related to lawn species richness, suggesting perception of species richness largely reflected that of non-lawn plants. Alpha diversity increased more rapidly, while beta diversity decreased less rapidly, for non-lawn plants than lawn plants with increasing spatial scale, although lawns had more species within individual yards. Conclusions Findings revealed a divergence in diversity-area relationships between different plant groups in residential landscapes. We should consider the ecological implications of unrecognized plant diversity, particularly in residential lawns, where management often strives to limit plant species richness.