Infestations of red mites left alone can eat enough chlorophyll out of the leaves of apple trees that the trees can’t store energy anymore, resulting in smaller fruit and a reduced fruit bloom the following season. Luckily we don’t often see red mite infestations due to a successful story of biological control in Pennsylvania. Dr. Dave Biddinger explained how to scout for red mites and maintain a successful biological control program at a Young Grower Alliance training session on July 16.
Make sure you know where apple scab overwinters, how to monitor and when it is most likely to appear. Penn State Tree Fruit Plant Pathologist Kari Peter met with Penn State Extension Young Grower Alliance (YGA) members for hands-on scouting and discussion of apple scab. Here are the key points she shared.
The third generation of Oriental fruit moth and the second generation of codling moth are active in most orchards in south-central PA. We are observing increased numbers of captured adult moths in sex pheromone traps located at various sites.
By now, everyone should have seen the results of their chemical thinning in apples. In my experience, the first few weeks after thinner application most growers think they took too many fruit off. However, by midsummer the crop load does not look too bad.
Cherry growers around the world use many training systems, both supported and freestanding. Choosing the right system depends on growing conditions, variety, rootstock, labor availability, and management skills.
During this past week we observed first brown marmorated stink bug (BMSB) adults maturing from eggs deposited earlier this season by BMSB adults from the overwintering generation. With the arrival of this generation, we expect an intensified movement of BMSB into orchards and more frequent occurrence of fruit injuries caused by this pest.
The extremely wet weather over the last month has triggered rot issues in both sweet and tart cherries. As a result of the volume of fungal spores flying around and the persistent warm wet conditions, peach and nectarine growers need to be on high alert as we are nearing the home stretch for harvest. Vigilant rot management strategies are critical this year to prevent brown rot (and other rots) during preharvest and postharvest. Management options, including organic strategies, are discussed. Conditions continue to be favorable for bacterial spot, necessitating shorter spray intervals for disease management.
The fact that spotted wing drosophila is being found in Maryland means that SWD is also likely to be present in warmer areas of Pennsylvania, and in the remainder of Pennsylvania shortly.
Anthracnose (also called ripe rot) in blueberry, has been quite severe this year, especially in highly susceptible varieties such as Bluecrop, Bluetta, and Blueray.
The beginning of July is a good time to start searching for the first male adults of spotted wing drosophila. Growers with late sweet cherries and sour cherries as well as blueberries and black raspberries should pay very close attention to possible movement of this pest into their plantings.
We are continuing to observe brown marmorated stink bug (BMSB) adults and nymphs in traps baited with a combination of BMSB aggregation pheromone. Now is the time to look out for the first adult male Spotted Wing Drosophilia.
Thanks to one of our growers we have been advised of a formula error in our spreadsheet.
The Tree Fruit Pathology Lab at FREC is seeking fire blight samples from around the state of Pennsylvania found in commercial orchards and home landscapes for evaluation for antibiotic-resistant strains of the bacteria and other projects.
The beginning of July usually marks a switch in our approach to control common insect pests in orchards.
Primary apple scab is finally over as of mid-June. Conditions have been ideal for canker blight: leftover fire blight cankers continue to grow and bacteria move within the tree to growing areas causing shoot blight. Conditions have been favorable lately for bacterial spot on peaches.
For a crop that may fruit for fifty years under the right care, it is critical to get blueberry plants off to a strong, healthy start.
Spotted wing drosophila (SWD), Drosophila suzukii, continues to be a problem for growers of soft-skinned fruit such as blackberry, blueberry, cherry (sweet and tart), and raspberry (black and red).
The potential for injury caused by brown marmorated stink bug adults and nymphs increased significantly during the last two weeks. It is time to start scouting for the presence of leafhoppers, especially in young orchards. Tufted apple bud moth and obliquebanded leafroller continue to be numerous in pheromone traps.
Conditions have been optimal for canker blight: leftover fire blight cankers continue to grow and bacteria move within the tree to growing areas causing shoot blight. Shoot blight is also occurring to those who experienced blossom blight, as well. Leafhoppers are active and will cause wounds in growing shoot tips, creating entry points for bacteria to enter. Pruning blighted areas and managing insects are the best methods for control.
The numbers of tufted apple bud moth and obliquebanded leafroller observed in pheromone traps in South-central Pennsylvania are similar to the numbers we observed 10 to 15 years ago, reaching over 100 moths per trap/week. Such high pest population levels require special insecticide applications targeting both leafroller species. This past week during our visual orchard monitoring we found the first eggs and nymphs of brown marmorated stink bug in commercial peach orchard. It is time to start scouting for the presence of leafhoppers, especially white apple leafhopper, potato leafhoppers and rose leafhopper.