The entomophilousTaraxacumandLeucanthemumare not generally regarded as harmful allergy causing plants because their pollen grains are normally not present in the air. However, walking throughTaraxacumandLeucanthemumvegetation causes an increase in the atmospheric pollen frequencies. The increase was studied with rotorod traps 0.25, 1 and 1.5 m above the ground. The controls were obtained 1 and 0.5 h before, and immediately after a 30 min walking through the vegetation. The collections were made on four days inTaraxacumand two days inLeucanthemummeadows with four trappings each day. Walking in the vegetation increased the pollen frequencies, especially at the 0.25 m level from 24 to 1404 pollen grains • m-3(Taraxacum) and from 32 to 4424 grains • m-3(Leucanthemum) but less at the 1.5 m height (from 14 to 59 ofTaraxacumand from 12 to 235of Leucanthemum). Thus small children playing on the ground, are subjected more to pollen than adults. The importance of the entomophilous pollen frequencies at various heights as an allergy causing factor should be studied further.