A pollen count of 100 - 500 grains per cubic meter is considered high. Here, on the southern piedmont, we laugh at this. Between the trees, grasses, weeds, and other flowering plants, each Spring, we experience counts in the thousands (over 10,000 has occurred more than once).
Accordingly, those with upholstered furniture on our screened porches bring indoors the cushions and cover our furniture that remains. With tree pollen already 100 or better, my wife and I undertook this task weekend before last. A few metal frame chairs are left uncovered until pollen season has passed.