The American black currant is also known as the wild black currant and is a member of the Saxifragaceae family. Black currants are susceptible to pests that affect the health of the plant.
Gall mites are a problem for black currants, infesting dormant buds in the summer. Another mite commonly found on the black currant is the spider mite, which is a member of the arachnid family. Boring insects such as the clear-winged borer often attack black currant plants and spread rapidly, causing the death of many plants.
Black currants infested with gall mites exhibit symptoms such as bud swelling, dry rosettes and dieback. Spider mites are characterised by fine silk webbing on the underside of plant leaves. These tiny mites produce symptoms such as distortion of leaves, too. Boring insects cause black currants to suffer from stem wilt, resulting in plant death.
Removing mites is accomplished by spraying the plant with a hard stream of water, which knocks mites from the tree. Applying horticultural soaps also eliminates mites. Boring insects are difficult to eliminate. Prune infested branches and search for other insects. Apply insecticides to the plant to reduce insects.