Variation in Insect Richness on Six Prairie Plant Species

Abstract

Abstract Insects play a fundamental role in ecosystem stability by providing important ecological services such as pollination, biological pest control, and nutrition for other organisms. Recent human-caused declines in insect populations mandate that we better understand how to improve and sustain insect diversity and abundance. The goal of our study was to identify the insects associated with 6 prairie plant species. We spent 248 hours over 3 months during 1 year monitoring insect visits to 10 replicates of ∼1-m2 patches each of Verbena brasiliensis (Brazilian Vervain, Verbenaceae), Pycnanthemum muticum (Blunt Mountainmint, Lamiaceae), Monarda fistulosa (Wild Bergamot, Lamiaceae), Eryngium yuccifolium (Rattlesnake Master, Apiaceae), Silphium gracile (Slender Rosinweed, Asteraceae), and Rudbeckia texana (Texas Coneflower, Asteraceae). We identified 11 bee species and 100 non-bee species representing 9 orders and 57 families. Insect richness varied widely among plant species: More taxa (n = 75) visited Blunt Mountainmint than any other plant species. Wild Bergamot had the fewest visiting taxa (n = 23). The majority of insects visited multiple plants, although we observed 2 bee species and 44 non-bee species on only 1 plant species. The number of unique insect visitors of each plant species varied from 1 to 19 taxa. Total insect richness was significantly greater in the morning than afternoon (χ2 = 3.7, P = 0.054). That plant diversity begets insect diversity is widely accepted, and our work suggests that inclusion of plants that are strong insect attractors could be integral to insect conservation and restoration initiatives.