Corylus avellana belongs to early spring pollen sources for Apis mellifera. The aim of the present study was to evaluate the dynamics of the Corylus pollen seasons over a 10-year study period (2001–2010). The study was carried out in Lublin by the volumetric method that is currently used in aerobiology. Years of abundant pollen production by this taxon were determined, as well as the period of maximum pollen release in each year, which is associated with the availability of large amounts of pollen to bees. Thermal conditions accompanying the beginning of pollen shed and the conditions prevailing during abundant pollen shed were presented. In particular years, the start of the Corylus pollen seasons was recorded between 9 January and 25 March, with an average temperature of 4.1°C. The duration of the pollen season varied between 19 and 78 days. Years of the highest hazel pollen production were as follows: 2006, 2010, 2007, and 2005. The period of pollen abundance, associated with the presence of high Corylus pollen content in the air, was recorded most frequently in the second half of March and at the beginning of April, with the average temperature between 2.4 and 14.4°C, with the 10-year mean value of 8.1°C. At the temperature of 8°C, the honey bee undertakes its first foraging trips, among others, to search for water and collect pollen. The present study showed that the nitrogen content in Corylus pollen grains was 4.82%, while the protein content 30.13%, which demonstrates the significant nutritional value of this pollen.

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