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Plant NameTypeDescription 
Fruit rotBlackberryDiseaseFruit rot is caused by a fungus. The disease is characterized by a watery, soft rot of infected fruit, either in the field or in storage. In moist conditions, the diseased fruit develops a characteristic coating of powdery, gray-brown fungus. The fungus can also attack canes, spreading from infected leaves into the cane and causing pale brown or "watermarked" gray and white lesions. The cane infections may also show fungal growth during humid conditions. The fungus typically overwinters in diseased plant debris and can be spread by wind and splashing water. The disease thrives in cool, moist weather and may cause serious fruit losses.
Leaf and cane spotBlackberryDiseaseLeaf and cane spot is a fungal disease affecting blackberries (including 'Marion' and 'Santiam') and blackberry hybrids (including 'Boysen' and 'Logan' berries). Leaf symptoms include development of characteristic lesions which are initially purplish, then turn tan to brown. The lesions later develop white centers with brown to purple margins. Cane symptoms are similar, but less noticeable. Severe leaf infections can cause premature loss of leaves, sometimes resulting in considerable leaf drop by late summer or early fall. The fungus overwinters on plant debris and is commonly spread by splashing water. A similar disease may occur on raspberries.
Brown marmorated stink bugBlackberryInsectThe 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. Damaged flower buds wilt and die. On fruit, BMSB feeding causes a sunken area on the berry surface at the puncture site. The flesh beneath is discolored and killed, resulting in distorted, misshapen, and shriveled fruit. Secondary damage from rot may also occur at the feeding sites. Other known fruit/nut hosts of BMSB include other 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
Raspberry crown borerBlackberryInsectThe adult raspberry crown borer is a clearwing moth with a wingspan of 1" to 1 1/2". The moth closely resembles a yellowjacket. Females lay eggs on the canes or leaf margins. The caterpillars hatch by fall (around October) and overwinter in small cells near the base of the canes. In the spring, the larvae tunnel deeper into the canes and feed inside the canes. The canes may appear swollen or galled as a result. The caterpillars spend a second winter in the canes before emerging as adults the following summer. The larvae are white with brown heads. During the second winter they are typically 1/4" long. They reach their full size of 1" to 1 1/2" long by the following summer. The borers can cause extensive damage to the canes, roots, and crown, weakening blackberries and related varieties including 'Logan' and 'Boysen' berries. They may cause death of raspberries.
Redberry miteBlackberryInsectThe redberry mite is an eriophyid mite. It is a tiny (1/50"), sausage-shaped, yellow mite which feeds primarily on the fruit of blackberries. The symptoms of redberry mite feeding are known as redberry disease. The mites feed between the drupelets (the small sections of the fruit) and at the core of the fruit. Affected fruits are hard and do not ripen normally. They are partly or entirely bright red (sometimes green), rather than black. Redberry mites overwinter in buds and in bark crevices, migrating to green fruit in the spring.
Spotted wing Drosophila (SWD)BlackberryInsectSpotted wing Drosophila (SWD) resembles other Drosophila species (fruit flies or vinegar flies) in appearance, but unlike other members of the family which attack only overripe, damaged or decaying fruit, SWD attacks healthy fruit as it ripens on the plant. Adult SWD flies are about 1/8 inch long, with red eyes and a yellow-brown body. Darker bands may be visible on the abdomen. Male flies have a distinctive dark spot on the leading edge of the wing near the tip. SWD is the only fruit fly species in our area with this spotted wing, making identification of males relatively simple. Females lack the spotted wing, but have a large, sawlike egg-laying organ called an ovipositor at the tip of their abdomen. It is used to deposit eggs in fruit (oviposition). The eggs are laid beneath the surface of ripening fruit as it begins to soften and show color (from first green-pink stage in caneberries), continuing through to harvest. Scars left by oviposition may appear as indented, soft spots on the fruit surface. Small white- or cream-colored larvae hatch within a few days and feed in the fruit, causing the fruit to soften and collapse around the feeding site. Further damage may be caused by secondary pathogens (fungi and bacteria) which attack the damaged fruit. At maturity, the larvae may be up to 1/8 inch long. They may pupate inside or outside the fruit. The length of the life cycle depends on temperature, with adults most active at cool temperatures (around 68 degrees F). Most soft-skinned fruits are vulnerable to attack by SWD, including peach, plum, cherry, grapes (table and wine), strawberry, blueberry, and cane fruits. It has also been found in Asian pear, fig, and hardy kiwi. See SWD under Common Insects for an additional image of the larval stage.