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Problem
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Plant NameTypeDescription 
AnthracnoseRaspberryDiseaseAnthracnose is a fungal disease. It occurs primarily on raspberry canes, but can also affect leaves and fruit. Initial infections typically occur on the lower portions of canes toward the inside of the plant. Canes show small, circular, sunken spots. These are initially reddish to purple, but enlarge and turn tan to gray with raised purple margins as the disease progresses. Severe infections may girdle canes, causing dieback. Leaves and leaf stems may show various degrees of purple spotting, depending on the plant variety. Berries affected by anthracnose may ripen unevenly and have abnormally small drupelets (the small sections of the fruit). The fungus is spread by splashing water and overwinters on infected canes. Black raspberries are susceptible, as are some varieties of red raspberries. Red raspberry symptoms may be limited to gray, unsunken areas on the canes.
Boron deficiencyRaspberryDiseaseBoron deficiency affects the level of growth hormones in plant tissue, as well as pollen tube growth. Bud break in the spring is delayed, and many buds die off. Other symptoms include abnormal or uneven shoot growth in the spring, malformed dark blue-green fern-like leaves; small and malformed crumbly fruit, and underdeveloped roots. Fruit ripening may be delayed, and overall yield is significantly decreased. Boron deficiency is relatively common in Western Washington and Oregon.
Fruit rot and cane BotrytisRaspberryDiseaseFruit 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. Black raspberries are commonly less affected by fruit rot than are red raspberries.
Phytophthora root rotRaspberryDiseasePhytophthora root rot can be a problem in the Pacific Northwest when raspberries are planted in areas with poor drainage. The fungus attacks the fine roots, which rot and die. Infected root tissue is cinnamon brown in color instead of a healthy white color. Rotten roots are unable to absorb sufficient water and nutrients, so canes wilt and leaves become withered and scorched during warm weather. Fruiting canes are usually shortened and may die prematurely with fruit failing to form or withering before maturity. The fungus produces overwintering spores that can survive for years in infected plant debris and soil.
Powdery mildewRaspberryDiseasePowdery mildew is a fungal disease which can affect leaves, shoot tips, new canes, and fruit of red and black raspberries, blackberries, and hybrids including 'Logan' berries. Leaves show pale green to watersoaked spots on the upper surface, with corresponding patches of white, powdery fungal growth on the lower surface. Infected young leaves do not expand properly, curling upward at the margins and becoming stunted and deformed. Shoot tips may be entirely covered with fungal growth. Severe infections cause the shoots to become spindly and weak, and may stunt the whole plant. Fruit may become covered with the fungus, fail to reach full size, and die. Small, black fungal structures may be present in the white mats on leaves and stems later in the season. Powdery mildew development is favored by warm, cloudy, humid weather. The fungus overwinters in infected buds.
Spur blightRaspberryDiseaseIn early April, pin-point size black fruiting bodies (perithecia) can be found in the gray affected areas of cane tissue. The fruiting bodies release ascospores, which infect leaves on both fruiting canes and primocanes. Brown necrotic spots with yellow margins form on fruiting-cane leaves when rainy weather lasts through late spring. Infected leaves become chlorotic and drop prematurely in severe cases. However, primocane leaves develop brown "V-shaped" lesions (with a yellow margin between the dead and living portion of leaves). The fungus then grows through the leaf stalk (petiole) and invades stem tissues around buds, turning them brown or purple. Buds on infected canes are more susceptible to winter injury, and fruiting laterals may be stunted. Infected areas become gray in winter. Spur blight is also found on Loganberry and Youngberry. The "Willamette" cultivar of red raspberry, while susceptible, suffers little damage and is considered "tolerant".
Yellow rustRaspberryDiseaseYellow rust is a fungal disease of the leaves and succulent tissues of red raspberries. Leaf infections occur in the spring, causing a yellowish to orange spotting on the upper surfaces. On the lower surface of the leaf in positions corresponding to the yellow spots, orange to pale yellow rust pustules appear in mid-summer. By fall, these pustules turn dark brown to black. Severe infections may result in premature drop of leaves, which may reduce yields and weaken plants. Fruit may fail to mature. Infected canes may be brittle and break off easily. The fungus overwinters as spores, primarily on debris and on the bark of previously infected plants. Wild caneberries including blackcap and salmonberry may also be infected.
AphidsRaspberryInsectAphids are small, soft-bodied, pear-shaped insects. They vary in color from yellow to green to brownish. Aphids on raspberries are typically found in colonies on the young growing tips of canes or on the underside of leaves. Feeding aphids can 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. Raspberry aphids can also transmit the raspberry mosaic virus, but spread of the virus is relatively slow. Aphids are not usually a serious problem on raspberries.
Brown marmorated stink bugRaspberryInsectThe 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 https://pubs.wsu.edu/.
Cutworms and armywormsRaspberryInsectCutworms and armyworms are the larvae of noctuid moths. These common moths are medium-sized with fairly dull coloration. The pale green to brownish caterpillars are hairless, nocturnal, and generally spotted, striped, or otherwise marked. They may be 1/4" to 1" in length and tend to curl up when disturbed. They climb into the plant and feed on buds, shoots, and foliage. Armyworm behavior is similar to that of cutworms, but armyworms feed in large groups instead of individually. They tend to be voracious feeders. The caterpillars typically spend the day just beneath the soil surface or under debris near the host. While armyworms oftentimes feed during the day, cutworms usually feed at night, so it is advisable to search for them with a flashlight in the dark. Weeds are a primary food source for both cutworms and armyworms.
Dryberry miteRaspberryInsectDryberry mites attack the fruit of blackberries (including 'Logan' and 'Boysen' berries) and raspberries. They are tiny, sausage-shaped, yellowish to brown eriophyid mites. The mites overwinter in bark cracks and under bud scales, and attack leaves and fruit. On the leaves, the mites feed on the underside, causing yellow blotching and reduced leaf size in some varieties. Affected fruits, particularly on 'Logan' berries, become brown and die shortly after petal fall. Red raspberry fruit may appear sunscalded, with whitish to tan areas of dead drupelets (the small sections of the fruit) often occurring at the stem end of the berry. Similar fruit symptoms on red raspberry can also be caused by other factors, including poor pollination or disease.
LeafrollersRaspberryInsectSeveral species of leafrollers can occur on raspberries and related plants. The caterpillars are typically light to dark green with light or dark heads, and are about 3/4" long at maturity. Typical symptoms of leafroller feeding include damaged buds and leaves that are rolled and tied with webbing. Leafrollers may also feed on ripe fruit. The larvae typically produce large amounts of webbing on the plants. Leafroller caterpillars are often active when disturbed, wiggling vigorously or dropping to the ground on a thread. The larvae often overwinter in webbed leaves or crevices on canes. The adult moths are 1/2" to 3/4" long and are brown or mottled tan and rusty brown. Some species have darker bands across the wings. Plants easily tolerate some damage from leafrollers, which are seldom serious pests. Leafrollers may be contaminants of harvested fruit.
LoopersRaspberryInsectLoopers are green caterpillars up to about 1 1/2" in length. They may have pale or dark stripes along the body. They are distinguished by their characteristic looping or "measuring-worm" movement. Loopers feed on leaves of many plants, chewing holes in the leaves or feeding along leaf margins. The adult of the alfalfa looper, a species common on raspberry, is a mottled brown moth with silver markings. Wingspan is approximately 1 1/2". The primary damage caused by loopers is the contamination of harvested fruit.
Raspberry beetle (raspberry fruitworm)RaspberryInsectRaspberry fruitworm (the larva) and raspberry beetle (the adult) are pests of raspberries and loganberries. The adults are yellow-brown beetles about 1/6 of an inch long. Raspberry beetles overwinter in the ground as adults, emerging from the soil in the spring (typically April-May). Adults feed on developing leaves, flower buds, and flowers. They leave characteristic slits between the veins of unfolding leaves as they feed. Injured blossoms often develop into distorted or malformed berries. Eggs are laid on flowers, buds, or stems. Hatching larvae burrow into the center of developing fruits, feeding in the receptacle (core) and drupelets for a month or more. The larvae are white with brown patches on the back of each body segment. At maturity, they are about 1/3 inch long. After the larvae finish feeding, they drop to the ground where they burrow into the top 3 inches of soil and pupate. If the fruit is harvested before the larvae drop, they remain in the fruit and are a significant contaminant of harvested fruit. There is typically one generation per year. Raspberry beetle also feeds and reproduces on wild blackberries, thimbleberries, and salmonberries.
Raspberry crown borerRaspberryInsectThe 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.
Root weevilsRaspberryInsectSeveral species of root weevils are common pests of raspberries. Adults are typically brown to black in color and may have lighter markings on the back. They range in size from 1/5" to 1/3" in length. These beetles cannot fly. Adults cause minor damage to plants by climbing up the canes and chewing ragged notches in the leaf margins. However, the most serious damage is done by the larvae. They are curved, legless, and white or pinkish with darker heads. They are found in the soil, where they feed on the roots. Severe root damage can occur, resulting in wilting and death of plants. Root weevils generally overwinter in the soil as larvae, with adults emerging in spring to early summer. Root weevil adults typically feed at night and spend the day on the ground or on the canes, where they may become a contaminant in harvested berries.
Rose stem girdlerRaspberryInsectThe rose stem girdler is a flat-headed, wood-boring beetle that is about 6 mm long. When it is young, it is black with a coppery red/bronze thorax. Later, the beetles are dark copper to greenish copper. The larvae are cream-colored. When the primocanes start to bloom, the larvae can be found feeding just below the bark. This feeding girdles the canes. Swollen stem galls are seen on some varieties. The girdling from this insect pest may cause the primocanes to die. If the canes are not killed, the next season's floricanes may not produce much fruit. The feeding damage weakens the canes making them more prone to winter damage.
Spider mitesRaspberryInsectSpider mites are tiny, eight-legged mites which may range in color from yellowish to green or red. Several species may occur on raspberries, including the twospotted spider mite. Spider mites typically feed on the underside of leaves, causing a yellowish stippling or speckling of the leaf. Severe infestations can cause entire leaves to turn yellow and drop, sometimes resulting in considerable leaf loss and reduced yield. Spider mite feeding is usually accompanied by webbing on the underside of leaves and between leaves and stems. Adults overwinter in plant debris or on canes. Mite infestations are worse in hot, dry, dusty conditions and are more common on red raspberries than on trailing berries.
Spotted wing Drosophila (SWD)RaspberryInsectSpotted 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.