The use of pheromone mating disruption, horticultural oils and some of the more selective reduced-risk insecticides and miticides will allow a natural increase of predators capable of regulating pest mite populations to tolerable levels without the use of miticides. The potential savings to Pennsylvania apple growers is approximately $1 million per year and a reduction of almost 1 ton of miticide active ingredient into the environment. Mite control through biological control in apple has the additional advantage of stopping the development of miticide resistance and, once established, is sustainable long-term if the use of certain harmful pesticides is avoided.
With the advent of uniform narrow canopy training systems on dwarfed trees with a simple branching structure that is enforced by renewal pruning, the “artistry” of pruning can be phased out in favor of pruning to a few scientifically sound principals. This article describes a prioritized set of pruning rules based upon these principals.
Spotted wing drosophila (SWD) is now being found more frequently in traps across the state, though numbers are still very low (0-3 per trap per week). Most recently a few female SWD were found in traps in blueberries in Adams County, and they have also been found in summer red raspberries in several locations in the state, as well as in low numbers in nearby states. This means that SWD adults in low numbers are now likely to be present in many berry fields, and that growers of summer raspberries, blueberries, and blackberries should now be planning on spraying their crops during harvest regularly to prevent future likely infestations. So should growers of fall berry crops.
Brown marmorated stink bug adults and nymphs are actively feeding on fruit, mostly peaches and nectarines, although nymphs were also observed on apples and cherries. At this time of the season, commercially available traps and lures for monitoring BMSB can provide a valuable tool to decide if insecticide treatments are needed. With continuous, vigorous growth of trees, populations of spirea aphids are abundant in most orchards, feeding at the top of still growing terminals. High populations of the European red mite are also being observed in some plantings.
The Penn State farm food safety webinar, "Update on the New FDA Produce Safety Standards: Issues of Importance for Pennsylvania Produce Growers", was presented on May 31, 2013 and now is available for viewing.
The tables below present weekly adult moth captures in pheromone traps and degree day comparisons for 2008 to 2013.
Sooty blotch/flyspeck infection period is underway and growers are encouraged to apply a cover spray. The latest infection periods have been posted, which include sooty blotch/flyspeck.
Bacterial spot of stone fruit (caused by Xanthomonas arboricola pv. pruni [Xap]) remains the most important bacterial disease of peach and nectarine in the eastern United States. We conducted a study in 2012 to monitor and identify populations of bacteria in stone fruit orchards, including bacteria resistant to the antibiotic oxytetracycline and to determine the current levels of oxytetracycline sensitivity in Xap populations. Of the 237 isolates tested, 99% and 81% grew in media amended with 5 and 10 mg/L oxytetracycline, respectively, while 25% and 22% of isolates grew in media amended with 15 and 20 mg/L and greater of oxytetracycline, respectively. Prudent use of this antibiotic is advised to prevent the loss of sensitivity.
BMSB adults as well as second and third instar nymphs were found feeding on fruit (mostly peaches and nectarines). If BMSB nymphs are spotted, the control treatment is needed immediately. While adult BMSB can continuously move in and out from any orchard, BMSB nymphs are resident pests and will continue feeding (and damaging fruit) for a consecutive 4 to 6 weeks. During the last week Japanese beetles (JB) were observed feeding in orchards located in southern Pennsylvania. Materials recommended for the control of brown marmorated stink bug should also provide effective control of JB.
Brown marmorated stink bug movement away from overwintering shelters is finally completed. BMSB adults are observed feeding on stone and pome fruit. The first egg masses and second instar nymphs were found during our weekly orchard observations. If BMSB nymphs are spotted, a control treatment is needed immediately. First generation codling moth (CM) flight continues in all areas across Pennsylvania. If pheromone trap captures indicate strong continuous CM flight, third applications of control materials will be needed. The second or third treatment of insecticides for the control of codling moth should also effectively control tufted apple bud moth (TABM) larvae. No Oriental fruit moth (OFM) control is required at this time.
The primary infection period for apple scab is nearing an end. Scab sources are still being sought in the region for fungicide resistance studies. Included is a thank you note to the attendees of the Spring Meetings.
With an alumni base of 600 strong, The Pennsylvania Rural-Urban Leadership Program (RULE) still has room to grow. Leadership is all over the map and it’s certainly in your part of Pennsylvania.
During this past week, relatively high numbers of adults (for this time of the season) were observed feeding on stone and pome fruit. The first egg masses and young nymphs were also found. If BMSB nymphs are spotted, a control treatment is needed immediately. Codling moth (CM) adults continue first generation flight in all areas of Pennsylvania. The second treatment of insecticides for the control of codling moth should also effectively control early tufted apple bud moth (TABM) larvae.
Have you ever looked for training materials to build the knowledge and confidence of your farm market personnel? Penn State Extension now offers on-line training for farm professionals that handle, process, or merchandise fresh market produce.
Update on the strawberry virus situation in Pennsylvania. Last month, I had written an article regarding two strawberry viruses (strawberry mottle virus, and strawberry mild yellow edge virus) that could be present in strawberry plug plants grown by mid-Atlantic nurseries (and others in the East) that had obtained runner tips from a Canadian supplier. The concerns were that the viruses could spread to otherwise healthy plants if aphids (the vectors of these particular viruses) were present; that the presence of the viruses would affect growers' plans to carry over plantings; and that if both viruses were present in the same plants, vigor and yields would be affected. At the time the article was written, we weren't sure how widespread the problem was in Pennsylvania.
Update on the current status of spotted wing drosophila, a species of fruit fly, that is problematic because the tiny larvae of this pest can be present in the fruit when it is harvested.
As a Pennsylvania grower of fresh vegetables and fruits, you have worked hard to learn about and adopt GAPs (Good Agricultural Practices) on your farm and in your packing house. Now that we are moving into peak marketing season, remember those farm food safety concepts when selling your produce at farm and farmers markets. Food safety practices that extend from farm to fork can help prevent foodborne illness outbreaks.
Adams County young growers were featured in the Gettysburg Times and Country Folks Grower.
The last twilight meeting of the season will be held at Mountain Valley Orchard in Cavetown, MD. In July, you have the opportunity to participate in the Penn State Fruit Research and Extension Center (FREC) Field Day, which will be held in conjunction with the International Fruit Tree Association Summer Study Tour. Registration is now open for both (see details under Events).
Peach leaf curl is occurring throughout the region; effective control measures occur after leaf drop in the fall. Weather conditions are still excellent for fire blight; growers are encouraged to keep young, newly planted blooming trees protected. Apple scab sources are being sought in the region for fungicide resistance studies.