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Plant NameTypeDescription 
Anthracnose (Leaf spot)Currant, GooseberryDiseaseAnthracnose is a fungal disease affecting the leaves of currants and gooseberries. Leaves show small, round or irregularly-shaped spots on the upper or lower surfaces. The spots are usually dark brown in color and may develop tiny, gray fungal structures in the centers. Severely affected leaves may turn yellow and drop prematurely. The leaf loss can weaken plants and reduce yields. Currant fruit may also show spotting. On fruit, the spots are tiny and resemble flyspecks. Severely infected berries crack open and drop. The fungus is spread from infected to healthy leaves by splashing water and overwinters in fallen leaves. Disease development is favored by wet spring weather.
Powdery mildewCurrant, GooseberryDiseasePowdery mildew is a fungal disease. Characteristic white patches of powdery fungal growth develop on shoots, fruit, and either or both sides of the leaves. Infected tissues are often stunted and distorted, and infected leaves may drop prematurely. On the berries, the fungal patches turn rusty brown as they age. Infected berries are typically smaller than normal, with rough, cracked surfaces. The fungus probably overwinters on twigs and infected plant debris and possibly also in buds. Disease development is favored by cool, rainy weather in the spring and early summer.
Brown marmorated stink bugCurrant, GooseberryInsectThe brown marmorated stink bug (BMSB) is an introduced pest species from Asia that is spreading quickly across the United States. Nymphs and adults feed on a wide variety of plant hosts. BMSB prefers to feed on fruit, seeds, and seed pods, but will also feed on stems and leaves of some hosts. Both adults and nymphs have piercing-sucking mouthparts and inject digestive enzymes into plant tissues to aid in feeding. BMSB feeding on berries typically causes a sunken area at the puncture site on the surface of the berry. The flesh beneath is discolored and killed, resulting in distorted and misshapen fruit. Secondary damage from rot may also occur at the feeding site. Other known fruit/nut hosts of BMSB include caneberries, blueberry, apple, pear, filbert, and stone fruits including apricot, cherry, and peach. One or two generations of BMSB per year are expected in the Pacific Northwest. Adults overwinter in sheltered locations (including houses, where they can become a significant nuisance pest). In the spring, light green to white eggs are laid in groups of about 20 to 30 on the underside of leaves. Young stink bugs, or nymphs, are black with a red-and-black striped abdomen. Nymphs often feed in groups when young. Older nymphs are dark with white bands on body, legs, and antennae. They may feed in groups or singly. Adults are a little over 1/2 inch long, with a shield-shaped body. Body color on adults is mottled gray and brown, while the legs and antennae have alternating dark and light bands. The abdomen also has dark and light bands which are visible at the edge of the wings. NOTE: BMSB adults closely resemble other stink bugs found in WA and OR. For more information on BMSB identification, see FS079E, Pest Watch: Brown Marmorated Stink Bug, available at
Currant aphidsCurrant, GooseberryInsectCurrant aphids are common on currants and are found occasionally on gooseberries. The aphids are small, soft-bodied, pear-shaped, yellowish insects. They typically feed on the underside of leaves, causing cupping and distortion of leaves. Infested leaves often show a yellow to reddish discoloration. Feeding aphids produce large amounts of honeydew, a sweet, sticky material which may attract honeydew-feeding ants or become covered with a dark growth of sooty mold. Honeydew and sooty mold can reduce the quality of fruit. Currant aphids overwinter as eggs on the bark of the host plant.
Gooseberry maggot (Currant fruit fly)Currant, GooseberryInsectThe gooseberry maggot is the larval stage of the currant fruit fly. The adult flies are about 1/5" long, yellow to orange in color, and have dark bands across the wings. In the spring, female flies lay eggs just under the skin of developing currant or gooseberry fruit. Hatching maggots burrow under the skin and feed in the berries. Infested berries turn reddish and may drop, sometimes causing severe fruit loss. The mature white maggots are about 1/4" long. They drop from the fruit to the soil, where they overwinter as small, brownish, pupae about the size of wheat grains. Adult fruit flies typically emerge in mid- to late April and May.
Imported currantwormCurrant, GooseberryInsectThe imported currantworm is the larva of a sawfly. The adult sawfly is black and yellow and is about 1/3" in length. The female lays eggs on the underside of leaves, near the midrib. The larvae feed along leaf margins, sometimes causing severe defoliation. The larvae are whitish at first, but become greenish with distinctive black spots and heads as they reach maturity. Mature larvae are about 1/2" long. They pupate in the soil beneath the host plants. A second generation may occur, appearing around June or July. Larvae overwinter in cocoons in the soil. Adults typically emerge in early spring.