Pollination Adaptation in Pedicularis Canadensis

During the spring of 1966 and 1967, operation of the pollination mechanism of Pedicularis canadensis L. flowers by nectar‐ and pollen‐foraging bumblebee ( Bombus Latr.) queens was observed in an Iowa relict prairie and was recorded by high‐speed cinematography. The stigma and style were found to sweep the forager's pronotum crevice as head and tongue were introduced into the 12‐mm corolla tube. Pollen deposited in the crevice was not removed as the forager's middle leg only groomed pollen laterally deposited on head and scutum. Thirty corbicular pollen loads from 417 foragers collected on nine prairie plant species included pollen from Pedicularis canadensis, Aquilegia canadensis L., Dodecatheon meadia L., and two unidentified plants not found in the prairie. The pollination mechanism was considered closely adapted morphologically and phenologically to bumblebee queens of eight species found foraging on Pedicularis .