Berries Production Guide

Currants & Gooseberries
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Insects

This section was updated - 26 June 2017

Insecticides such as Malathion, Assail and Exirel are toxic to bees. Avoid applying them during the blossoming period. If they must be applied when bees are in the field, take the precautions listed in the section "Pollination" in this guide to avoid killing bees.

Note: The recommended spray rates are for mature bushes unless otherwise specified. For smaller, immature bushes use reduced amounts of spray mixture.

Aphids

Hosts

Several species attack currants and gooseberries.

Damage

Aphids attack the growing tips and the undersides of leaves. Leaves become curled and yellow mottled and often develop red-coloured blisters. Older leaves may become sticky from “honeydew” secreted by the aphids. New growth becomes stunted and yields can be reduced.

Identification

The currant aphid is the most common species. Adults are greenish yellow, about 2 mm long.

Life History

Currant aphids over winter as eggs on new canes. They hatch when leaves begin to open and start feeding. Each generation takes about two weeks.

Monitoring

Start monitoring when the leaves first open and continue weekly. Check growing tips and the underside of new leaves.

Management

Cultural Control

Excessive nitrogen can produce lush growth and result in increased aphid populations.

Biological Control

Ladybird beetles, syrphid larvae, and parasitic wasps usually provide adequate control of aphids, especially in mature plantings. Assess levels of natural beneficials before applying insecticides.

Chemical Control

If aphid populations are increasing in the absence of beneficials, apply:

Malathion 25W (25% malathion) at 2.0 to 2.5 kg/1000 L of water. Spray bushes thoroughly. Do not apply within 3 days of harvest; or

Note: Malathion must be applied when the temperature is 20° C or higher to be effective.

Assail 70WP (70% acetamiprid) at 56 to 86 g/ha (22 to 34 g/acre) in a minimum of 187 L/ha (75 L/acre) of water by ground application. Do not apply more than 4 times per season. Do not apply more than once every 12 days. Do not apply during bloom as Assail is toxic to bees directly exposed to treatment. Do not apply within 7 days of harvest; or

Exirel (100 g/L cyantraniliprole) at 750 to 1500 mL/ha (300 to 600 mL/acre) in enough water to obtain good coverage. Use the high rate when pest pressure is heavy. Do not apply during bloom as Exirel is toxic to bees. Do not apply more than 4 times per season or a maximum of 4.5 L/ha (1.8 L/acre). Tank mixes and sequential applications with strobilurin (Pristine, Cabrio), copper and captan fungicides are not recommended as crop injury has resulted under lab settings. Do not apply within 3 days of harvest; or

Sivanto Prime (200g/L flupyradifurone) at 500-750 ml/ha (196-295 ml/acre) in a minimum of 100 L/ha (40 L/acre) of water as a directed foliar spray. Do not apply more than once every 7 days. Do not exceed 2000 ml/ha (787 ml/acre) per season. Do not apply within 3 days of harvest.

Currant Borer

Hosts

Currants, gooseberries, black elder, sumac.

Damage

The larvae bore into the canes resulting in undersized and yellowish foliage development in the spring. These canes usually die within two to three weeks.

Identification

The adults are thick bodied, clear winged moths, about 13 mm long, steel blue in colour with black and yellow markings. The boring larvae are white with brown heads and reach 13 mm in length.

Life History

Nearly mature larvae over winter in the canes just above ground level. In the spring they feed for a short time, pupate within the cane and emerge as adults in June / July. In the summer months the adults lay eggs on the canes.

These soon hatch and the young larvae bore into and tunnel within the canes.

Monitoring

Look for wilting and dying canes in the spring. Watch for the distinctive, clear-winged moths on bright warm summer days in late June and July. Phermone lures are available and can be used in traps to determine population levels of this insect. Consult BCAGRI or your pest advisor for more information.

Management

Cultural Control

Prune out dead wood in the fall. Cut off and burn infested canes before moths emerge in June.

Biological Control

There are currently no commercial biological controls for this pest. Mating disruption techniques are being researched.

Chemical Control

There are no insecticides registered for this pest. 

Currant Fruit Fly

Hosts

Currants, gooseberries, wild currants

Damage

Maggots feed inside the berries, making them unmarketable. Infested berries drop prematurely.

Identification

The adult fly is yellowish, 6 mm long with bands across the wings. The maggots are white and tapered at the head end.

Life History

There is one generation per year. They over winter as pupae in the soil below bushes. The adults emerge in May when the currants flower. They then lay eggs in the developing berries. Larvae hatch and feed within berries until July.

Monitoring

There are no reliable early detection techniques available for this pest.

Management

Chemical Control

Spray to protect the green fruit immediately following flowering. Do not spray during flowering to avoid killing bees. Repeat spray in 10 - 14 days. Apply:

Malathion 25W (25% malathion) at 2.0 to 2.5 kg/1000 L of water. Spray bushes thoroughly. Do not apply within 3 days of harvest; or

Note: Malathion must be applied when the temperature is 20°C or higher to be effective. Although malathion may be applied up to 3 days before harvest, sprays applied later than recommended will not provide control of fruit flies.

Success or Entrust applied for leafrollers will also provide some protection against currant fruit fly.

Leafhoppers

Host

Currants and gooseberries.

Damage

Leafhoppers seldom reach damaging levels in BC. The nymphs feed on the undersides of leaves and, when abundant, cause white speckling gradually turning the whole leaf yellowish and brown. Plants lack vigour and fruit size is reduced.

Identification

Nymphs are small, pale white insects which feed on the undersides of leaves. Adults are slender and about 3mm long. They hop and fly when disturbed.

Life History

There are two generations per year. Leafhoppers over winter as eggs under the bark of the canes. These hatch in May and feed as nymphs for three to four weeks before becoming adults. The next generation occurs from July to September and lays over wintering eggs.

Monitoring

Check leaves for leafhoppers and speckling in May.

Management

Chemical Control

Apply when leafhopper populations begin to build:

Malathion 25W (25% malathion) at 2.0 to 2.5 kg/1000 L of water. Spray bushes thoroughly. Direct sprays and use enough pressure to ensure that the undersides of leaves are thoroughly covered. Do not apply within 3 days of harvest.

Note: Malathion must be applied when the temperature is 20°C or higher to be effective.

Leafrollers

Hosts

Many berry, fruit and ornamental crops.

Damage

Caterpillars feed on developing blossoms and berries and on leaves from within rolled-up shelters.

Identification

There are several leafroller species. The moths are small and vary in colour from tan to grey and often have patterns on the wings. The larvae vary in colour from pale yellow to dark green to black and can reach 15mm in length.

Life History

Most leafrollers over winter as eggs under loose bark. The eggs hatch in early April and the larvae feed until June when they pupate. The resulting moths emerge in July and lay over wintering eggs or, in some species, produce a second generation.

Monitoring

Look for young larvae on developing buds in the spring. When leaf rolling begins, the severity of the infestation can be estimated by the number of rolled leaves. Use monitoring guidelines and thresholds described in the raspberry section of this guide.

Management

Cultural Control

Pruning and weed control reduces numbers by removing over wintering sites.

Biological Control

Leafrollers have a number of natural enemies that usually keep populations at low levels.

Chemical Control

DiPel 2XDF (Bacillus thuringiensis) at 0.525 to 1.125 kg/ha (210 to 450 g/acre) in 600 L water/ha; or

Altacor (35% chlorantraniliprole) at 215 to 285 g/ha (86 to 114 g/acre) in enough water to ensure good coverage. Use the high rate when insect pressure is heavy. Do not apply more than 3 times per season. Do not apply more than once every 7 days. Do not apply within 1 day of harvest; or

Exirel (100 g/L cyantraniliprole) at 500 to 1000 mL/ha (200 to 400 mL/acre) in enough water to obtain good coverage. Use the high rate when pest pressure is heavy. Do not apply during bloom as Exirel is toxic to bees. Do not apply more than 4 times per season or a maximum of 4.5 L/ha (1.8 L/acre). Tank mixes and sequential applications with strobilurin (Pristine, Cabrio), copper and captan fungicides are not recommended as crop injury has resulted under lab settings. Do not apply within 3 days of harvest; or

Success 480SC (480 g/L spinosad) at 145 to 182 mL/ha (58 to 73 mL/acre) in 300 to 500 L/ha of water. Use the upper rate under high insect pressure and/or on large larvae. Apply a maximum of 3 times per year and do not apply within 3 days of harvest; or

Entrust 80W (80% spinosad) at 80 to 109 g/ha (32 to 44 g/acre) or Entrust SC (240 g/L spinosad) at 267 to 364 mL/ha (107 to 146 mL/acre) in 300 to 500 L/ha of water. Use the upper rate under high insect pressure and/or on large larvae. Apply a maximum of 3 times per year and do not apply within 3 days of harvest. It is OMRI approved for organic production.

Sawfly (Currant Fruitworm)

Hosts

Red currants and gooseberries. Black currants are rarely attacked.

Damage
The larvae feed on the leaves and can quickly defoliate plants if the infestation is severe. They feed from the edge of the leaves inward, and from the centre of the plant outward.

Identification

The larvae are many-legged, greenish, smooth with many small black spots. The adults are small (8 mm) black sawflies, not moths, with yellowish marks on the abdomen.

Life History

The winter is spent in a cocoon in the soil. The adult sawfly emerges in early spring and lays eggs on the foliage. Larvae hatch and feed through late May and June. A second generation begins in later July.

Monitoring

Because the larvae are voracious feeders, plants should be monitored weekly for signs of feeding. The early stages of feeding are easy to miss - monitor inner parts of the plants carefully for signs of larvae and damage.

Management

Chemical Control

Because defoliation can occur in a few weeks, sprays should be applied at the first signs of feeding. Damage may be localized in a planting, so only certain areas may need treatment. Malathion sprays as applied for other pests will control sawfly larvae.

Scale Insects

Scale insects are an occasional pest on older wood in currants and gooseberries. They look like small lumps or growths on the woody tissue. Good renewal pruning usually provides adequate control, aided by beneficial insects if spraying is limited.

Spider Mites

Hosts

Currants, gooseberries and many other fruit, vegetable and ornamental crops.

Damage

Spider mite outbreaks can occur after insecticide sprays applied for other pests upset the predator mite balance. Heavy mite feeding can cause leaves to become yellow-flecked and plant vigour can be affected.

Identification

Spider mites are very small, slow moving, eight-legged creatures feeding on the undersides of leaves.

Life History

Mites over winter as adults on the plants. They become active during the warm spring days when the leaves begin to open. They have several generations per year and all stages usually occur at the same time.

Monitoring

Mite presence is usually first noticed as yellow flecking on the leaves. When first noticed, weekly checks should be made using a hand magnifying lens.

Management
Biological Control

Spider mites are usually kept at low levels by naturally occurring predatory insects and mites. Predatory mites are reddish and move more quickly than spider mites. Predators can be purchased for release into fields. See raspberry and strawberry sections of this guide for more information.

Chemical Control

Malathion 25W (25% malathion) at 2.0 to 2.5 kg/1000 L of water is registered for mites, but control will likely be only partial. Spray bushes thoroughly. Direct sprays and use enough pressure to ensure that the undersides of leaves are thoroughly covered. Do not apply within 3 days of harvest.

Note: Malathion must be applied when the temperature is 20 C or higher to be effective.

Spotted Wing Drosophila

Hosts

Berries, stone fruits and numerous wild hosts

Damage

Female flies lay eggs under the skin of ripe fruit. Larvae hatch and begin to feed within the fruit, causing softening in the area of feeding. There can be several larvae in a fruit, which hastens softening and fruit collapse. Holes the size of pin pricks are evident within the soft areas of infested blueberries.

Identification

Adults: 2-3 mm (1/8 inch) long, brownish with red eyes and clear fly-like wings. Males have a black/grey spot on the end of each wing, as well as two black ‘combs’ or bands on each front leg. The females do not have spots or leg bands. Females have saw-like egg-laying organs (ovipositors) that are used to cut into fruit skin. Ovipositors are easier to see when extended. A hand-lens or dissecting microscope is needed to identify ovipositor.

Eggs: 0.6 mm long, oval, white, 2 filaments at one end.

Larvae: Legless, headless, up to 6 mm long at maturity, milky-white.

Pupa: 3 mm long, brown, football-shaped, two stalks with small finger-like projections on ends.

Life History

SWD over winter as adult flies. In spring flies become active and lay eggs in ripening fruit. Based on climate model predictions, there could be up to five generations per year in BC. Generations overlap as flies are relatively long-lived particularly at temperatures of 20°C and cooler. Based on Japanese literature, a female can lay eggs for 10-59 days, with 7-16 eggs laid per day, and average 384 eggs per female. Eggs hatch in 2 72 hours, larvae mature in 3-13 days, and pupae reside in fruit or outside of fruit for 3-15 days. In the lab at constant temperature, one generation takes 50 days at 12°C, 21-25 days at 15°C, 19 days at 18°C, 8.5 days at 25°C, and 7 days at 28°C. Adults are attracted to and feed on ripe and decaying fruit.

Monitoring

Flies can be monitored with cup-like traps baited with apple cider vinegar. Place traps when the temperature is consistently over 10°C and/or before fruit starts to ripen. Hang traps in the plant canopy in a shady location. Check traps once per week and look for the SWD adults in the bait solution. Use a hand lens or other magnifier to see the female ovipositor. Replace the bait solution each week. Suspect fruit can also be collected and inspected for larvae.

Management

Cultural control

Where practical, remove or bury cull fruit to eliminate additional feeding and breeding sites. Keep equipment and processing areas free of old fruit. Think beyond the borders of your farm and be aware of host plants in adjacent fields. Encourage neighbours to also manage for SWD. Shorten picking interval where possible: pick early, clean and often.

Biological control

To date, there are no commercially available biological controls for SWD. Research is underway to identify potential predators and/or parasites that may be useful in managing SWD.

Chemical control

Chemical control will be required if trapping shows that adult SWD flies are present in the field when berries begin to ripen. Adults are the target and are killed by direct spray contact and/or when they are exposed to residues of insecticide on the treated fruit and leaves.

Consider the following when planning a spray program:

1. All of the recommended products are toxic to bees. Avoid application when crops are blooming and bees are in the field. If sprays are necessary during this time, they should be applied at night.
2. Use enough water and pressure to ensure adequate coverage (up to 500 L/ha of water). Flies prefer to feed in the lower, shaded part of the canopy.
3. Use spray equipment that will allow effective coverage. Currently, no products are registered for aerial application.
4. To limit development of resistance, rotate between the recommended products.
5. A 7 – 14 day spray interval may be necessary to protect fruit through the ripening period depending on temperature and pest pressure.
6. A post-harvest spray may be necessary to prevent flies from building up on residual fruit and spreading to adjacent later ripening crops.

The following products are registered for SWD control:

Delegate WG (25% spinetoram) at 315 to 420 g/ha (126 to 168 g/acre). Do not apply more than 3 times per year. Allow a re-treatment interval of at least 7 days. Do not apply within 3 days of harvest; or

Entrust SC (240 g/L spinosad) at 333 to 444 mL/ha (133 to 178 mL/acre). Minimum re-treatment interval is 5 days. It is OMRI approved for organic production. Do not apply more than 3 times per year and do not apply with 3 days of harvest.

Exirel (100 g/L cyantraniliprole) at 1000 to 1500 mL/ha (400 to 600 mL/acre) in enough water to obtain good coverage. Do not apply more than 4 times per season or a maximum of 4.5 L/ha (1.8 L/acre). Tank mixes and sequential applications with strobilurin (Pristine, Cabrio), copper and captan fungicides are not recommended as crop injury has resulted under lab settings. Do not apply within 3 days of harvest.

The following products received emergency registration for SWD in 2017

Malathion 85E (85% malathion) at 1 L/ha (400 mL/acre) in up to 1000 L of water. Apply when the temperature is 20°C or more.  Apply between June 1 and November 30, 2017. Do not apply more than 2 times per year. Do not apply within 3 days of harvest

For more information see supporting document: Spotted Wing Drosophila Brochure

Weevils (Clay-coloured Weevil, Black Vine Weevil, other species)

Hosts

Currants, gooseberries, other small fruits and ornamentals

Damage

Adult weevils feed on the opening buds in the spring on warm nights. Later in the growing season they feed on the ripening fruit and in the leaves, leaving notches along the edge. The larvae eat the bark off the roots, weakening or killing plants.

Identification

The adults are night feeders so are seldom seen. They are about 1 cm long with long tapering downward-curved mouth parts. The grubs are whitish with brown heads and they are found in a curled C-shape.

Life History

Most weevils over winter as adults in the soil. They climb the plants on warm spring nights to feed. In May to July eggs are laid in the soil where the grubs feed on the roots throughout the summer. There is one generation per year.

Monitoring

Adult weevils can be found by checking a planting after dark. Shaking the upper foliage over a white piece of paper or beating tray is effective in finding weevils. Since the adults cannot fly, infestations are often first localized near the edges of the planting.

Management
Chemical Control

Sprays must be applied before egg laying occurs - in late April for clay-coloured weevils and late-June for black vine weevil control:

Exirel (100 g/L cyantraniliprole) at 1000 to 1500 mL/ha (400 to 600 mL/acre) in enough water to obtain good coverage. Use the high rate when pest pressure is heavy. Do not apply more than 4 times per season or a maximum of 4.5 L/ha (1.8 L/acre). Tank mixes and sequential applications with strobilurin (Pristine, Cabrio), copper and captan fungicides are not recommended as crop injury has resulted under lab settings. Do not apply within 3 days of harvest; or

Actara 25WG (25% thiamethoxam) at 210 to 280 g/ha (84 to 112 g/acre) in sufficient water to obtain coverage of foliage. Apply when weevils or weevil damage is detected. Repeat application if insect populations rebuild. Use the higher rate for heavy infestations. Do not apply more than twice per season. Do not apply within 3 days of harvest; or

Malathion sprays as applied for other pests will also kill adult weevils.

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