concentrations at canopy height ranged between 250 and
420 grainsm3 from 13 to 17 July and reduced to 95 grainsm3
on 19 July. Also, on four consecutive days (14–17 July, Fig. 5b–e)
diurnal distributions of pollen concentration were bi-modal,
similar to those measured by Flottum et al. (1984), with a
second lesser peak occurring for most elevations between 1100
and 1200 EDT.