highly significantP<0.05
Spearman rank correlation analysis shows that specifically in Alnus , Betula , Corylus , Fraxinus , Quercus and Plantago both temperature in the year prior to (T -1 ), as well as in the growing season (T), are highly significant factors (T April r s between 0.30 [P<0.05[ and 0.58 [P<0.0001]; T Juli-1 rs between 0.32 [P<0.05[ and 0.56 [P<0.0001]) in the annual pollen influx of wind-pollinated plants.