Raspberry & Blackberry Pest and Disease Alerts

Our friends at Cornell Cooperative Extension share these tips for managing pests and diseases in raspberry and blackberry during this unusually wet summer.

Tarnished plant (lygus) bug levels are high in caneberries. We’re also seeing some damage to cut flowers following feeding on buds.  Insect feeding through buds, in open blooms, or on developing fruits stunts berries. Cornell Guidelines suggest a threshold of 10-20% infested canes. In caneberries Assail, Befenture 10DF, carbaryl/Sevin, Danitol, are labeled; Brigade DF can be used in caneberries but isn’t labeled for TPB but will provide incidental control used for other labeled pests (Brigade also has a supplemental label in NY for spotted-wing drosophila). In organic production Mycotrol, Grandevo, PFR-97 and PyGanic are labeled, but emphasize good weed management. (This information is from Dan Gilrein, CCE Suffolk.)

Spur blight (Didymella applanata) has unsurprisingly reappeared in many cane berry plantings. This fungal disease loves the wet humid weather we are having. Dense plantings usually have problems even in dry years, but this year even well-pruned plantings may see this disease. Chocolate brown to purple blotches appear at the buds of canes. This results in weak or no growth from those buds and an overall lack of vigor. 

Prune and destroy diseased canes before next spring. There are plenty of fungicides labeled for this disease but take care when applying at this time of year, especially in hot weather. You can get foliar burn from some of the pesticides. The best time for control is delayed dormant in the spring. 

Cane blight (Leptosphaeria coniothyrium) are similar in appearance to spur blight, but the lesions can be found all along the cane. Often the two diseases appear together. Cane blight is more common in black and purple raspberries, but can also infect red raspberries. Prune and destroy infected canes asap. Best control comes from delayed dormant sprays of lime sulfur. 

What You Need to Do for a Successful Blueberry Harvest This Summer

Our friends at Cornell Cooperative Extension have shared these important tips for ensuring the success of this season’s blueberry crop.

Blueberry harvest is underway and looks surprisingly good in most places – despite the May freeze, early drought, and occasional hail events around the region. Fruit is sizing very well and plant growth is great – these plants LOVE all this rain! But unexpected weather is when you will discover how effective your disease management program was.

Anthracnose fruit rot (Colletotrichum acutatum) is widely apparent in plantings. This disease should be prophylactically sprayed before and during bloom. You can spray now in hopes that you can thwart the spread of the disease, but look carefully at the REI and days to harvest all chemicals.   

This disease will present as a sunken spot on the fruit. In this humid weather, you will undoubtedly see the pink-orange fruiting spores that will grow on the sunken areas. Make a note to focus on next season to control this disease.

Mummyberry (Monilinia vacinii-corymbosi) is less widely apparent, but definitely out there. Mummyberry spores can be moved by pollinators, so even if you’ve never dealt with this disease before, there is always a chance. That is why we encourage growers to manage for it, despite the history in your own patch. This disease is controlled at the vegetative green tip – so pretty early in the spring. 

Blueberry tip borer moth (Hendecaneura shawiana) is a pest that we are seeing much more frequently than in the past. The pest doesn’t damage the fruit from this season. But the overall impact is more significant. The moth lays eggs in the tip of the newest canes, causing the cane to abort vertical growth and branch much lower than it normally would. This means that there is less opportunity for overall growth, the fruiting wood is too low, and over time the plant becomes less productive due to the architectural change. 

The small brown moth lays eggs in June, which hatch in July. The larvae drill down several inches, causing distortion and then death of the shoot tip. This flagging can look something like canker, but it’s more localized to the top 6” of the shoot. There are no labeled conventional insecticides. Use azadirachtin and pyrethrin products at petal fall for control.  

Japanese beetle (Popillia japonica) have started feeding on blueberry foliage. I’ve yet to get a report of fruit feeding, but that is when they become a problem worthy of spraying. Despite the foliar damage, they usually don’t do lasting damage to the plant. There are many pesticides that can be used on this insect, but don’t pull the trigger unless you really need to and make sure to read the label for Days to harvest. 

Canker diseases (Fusicoccum putrefaciens and Phomopsis vacinii) are exhibiting the tell-tale cane flagging. New shoots will wilt rapidly and die back from the tip towards the crown. Healthy vigorous canes will wilt and collapse. When you see this happen in an otherwise perfectly healthy plant, the likelihood is high that it’s canker. Fusicoccum canker forms bulls-eye type lesions on the stem, which is another diagnostic help. Prune the dead out as it appears and make a note to use a delayed dormant spray next spring.  

UNH Seeks Commercial Farmers to Trial Advanced Kiwiberry Selections

The University of New Hampshire Kiwiberry Research and Breeding Program is now 10 years old, and has nearly 20 advanced breeding lines ready for multi-locational testing. They’re looking for 25 farmers across the northeast who are interested in participating in a grant-funded project that will support participatory evaluation of these potential new varieties, starting spring 2023.

If you are a current or aspiring kiwiberry producer, have an interest in new varieties, wish to receive more technical training, and have room for at least 12 vines, please complete this short questionnaire. If you would like to learn more about kiwiberry, a production guide developed by our program is available online at this link.

SWD ALERT!

SWD ALERT!

Cornell has reported sustained SWD catches in several counties. Numbers are not high yet, but have been increasing. Be vigilant in your trap and fruit monitoring, weeding, and irrigation/drainage, and employ a spraying routine that works with your picking schedule. Follow this basic guide:

• Maintain an open canopy to increase sunlight and decrease humidity
• Eliminate weeds within rows to increase sunlight penetration and improve spray penetration into and deposition on the canopy
• Repair leaking drip lines and avoid overhead irrigation when possible. Allow the ground and mulch surface to dry before irrigating, and eliminate areas that encourage puddles.  
• If you’ve set your own traps, check them regularly—daily, if possible. Females usually arrive first, but males are quick to follow.   
• Check your fruit regularly. Pick groupings of 15-25 ripe fruit from different locations in your field, especially along the edges. Lightly squeeze each fruit. In a resealable bag, mix 1 cup salt and 1 gallon water. Add the fruit and mix well. After 30 minutes, check for small white larvae floating at the top. Repeat for each fruit grouping.
• Apply pesticides every 5 to 7 days; repeat if it rains.
• Rotate pesticides to prevent resistance.         

Visit Cornell's blog for detailed information on monitoring and growing best practices during SWD season. Download the university’s list of approved SWD insecticides here. 

The Health Benefits of Berries

The Health Benefits of Berries

Vitamin and Flavoid-packed Powerhouses

Beyond their ability to add flavor to and complement a variety of savory and sweet recipes, berries are vitamin- and flavonoid-packed powerhouses. Get to know more about each berry and how it can benefit your health.

Blueberry

• Consistently ranked as one of the top antioxidant foods—twice the concentration of spinach, and three times the amount found in oranges and grapes!
• High in vitamins C and K, and manganese
• Good source of fiber
• The newest research suggests that blueberries may reduce the risk of heart attack and be beneficial in halting age-related memory decline

Strawberry

• Packed with vitamin C (one serving has 150% of the recommended daily value)
• High in antioxidants
• Good source of fiber, folate, potassium, and manganese

Blackberry

• One of the earth’s strongest antioxidant foods, with high levels of polyphenolic compounds including ellagic acid, quercetin, and cyanidins
• High level of fiber
• High levels of vitamins C and K, manganese, and folic acid

Raspberry

• Packed with fiber
• High levels of vitamin C; vitamins B1, B2, and B3; magnesium, folic acid, and iron
• High levels of antioxidants, including catechins, salicylic acid, and anthocyanins
• Contain raspberry ketone, which some preliminary studies suggest may be helpful in weight control