What's eating my trazel?

Trazel (Corylus × colurnoides, a Turkish hazel × common hazel hybrid) inherits hazel's typical pest profile. Hazelnut weevil attacks developing nuts, grey squirrels take the crop early, and big bud mite causes blind buds. The Turkish hazel parentage generally confers good vigour and some disease tolerance, but nut pests apply equally.

Larvae bore into developing nuts, leaving empty shells and causing premature nut drop; up to 80% crop loss in heavy years. Shake adults from branches onto a sheet in spring and destroy them. Remove fallen infested nuts promptly. Kaolin clay sprays at bud burst reduce adult feeding damage.

Harvest nearly all nuts before natural drop, reducing or eliminating the edible crop. Net canopy at ripening in late summer. Harvest as soon as nuts reach maturity rather than waiting for natural fall.

Abnormally swollen, rounded buds that fail to open; affected shoots produce no growth or crop. Identify and remove swollen buds in late winter before mite dispersal in spring. In severe cases, hard-prune affected branches.

Sticky honeydew on foliage, minor leaf curl, and sooty mould; rarely causes serious damage in established trees. Encourage beneficial insects. Apply insecticidal soap to heavily infested shoots if natural predators are insufficient.