Fig. 1.

A: Passive pollen sampler, as described by Ott and Peters, with additional pin holes to hold multiple slide holders. Two microscope slides, labeled A1 and A2, are placed in plastic slide holders inserted into pin holes. B: Plastic microscope slide holders, made to hold standard size microscope slides. Includes groove in base for easy slide removal. Slide is raised 6 mm above the bottom plate of the shelter. C: Assembled passive pollen sampler, mounted on l-bracket and fence post 1.8 m above the ground.