nature closeup blossom alder tree pollen in spring

adler alder allergy alnus background beautiful beauty betulaceae betulus birch bloom blooming blossom blue botanical botany branch bright brown bud buds bush carpinus catkin catkins close closeup color cone day deciduous decorative detail earring environment flora floral flower foliage forest fresh garden glutinosa green growth hazel inflorescence landscape leaf leaves macro medical natural nature nobody organic ornamental outdoor outdoors park plant pollen season seasonal seed shrub sky spring springtime stem summer sunny tree twig wood yellow young