{"id":1068,"date":"2018-05-06T06:14:45","date_gmt":"2018-05-06T10:14:45","guid":{"rendered":"https:\/\/blog.uvm.edu\/fruit\/2018\/05\/06\/apple-crop-management-this-week\/"},"modified":"2018-05-06T06:14:45","modified_gmt":"2018-05-06T10:14:45","slug":"apple-crop-management-this-week","status":"publish","type":"post","link":"https:\/\/blog.uvm.edu\/fruit\/2018\/05\/06\/apple-crop-management-this-week\/","title":{"rendered":"Apple crop management this week"},"content":{"rendered":"

By Terence Bradshaw<\/a><\/p>\n

Apple buds are rapidly expanding into tight cluster bud stage in most of Vermont, which sets the calendar close to \u2018normal\u2019 after the cool, slow start to the season. Apple scab infection periods have been somewhat scarce, depending on when you started you clock for ascospore maturity (green tip, minus any confidence you have in slow maturation of a low inoculum<\/em> population because your orchard was clean last year). We potentially had an infection period April 27-May 1 right at green tip with low ascospore maturity and little tissue open; some had an infection period May 3-4, and others may be waiting for the first one that could occur today and into tomorrow. You should be covered with a protectant going into this event, and if you aren\u2019t or question your coverage, plan on applying a material with kick-back activity like one of the Lunas, Merivon, Inspire Super, or even one of the older strobilurins or DMI fungicides (if they still work against your local population) this morning or early tomorrow.<\/p>\n

Once we get through today\u2019s rains (and the likely overnight wetting event), the warm, sunny weather this week is going to push disease management to the side for a spell but will push bud phenology and insect activity along. Growers who use them should already have traps deployed for tarnished plant bug (TPB) and European apple sawfly (EAS), which are attracted to blossoms (thus the use of white sticky cards to catch them in the canopy). Compare cumulative mean catch per block to our monitoring chart<\/a> to determine the need to treat.<\/p>\n

That said, there are important considerations to make when determining the need for prebloom insecticides. At the time the accepted thresholds were established, the majority of Vermont\u2019s apples were sold to wholesale markets with little tolerance for cosmetic blemishes like TPB or a low infestation of EAS may cause. However, increased direct-marketing of apples today may increase consumer tolerance for those \u2018ugly\u2019 fruit, so really consider your own tolerance for damage before applying a broad-spectrum material. Then again, I\u2019ve seen EAS infestations that looked worse than an unmanaged codling moth outbreak and where the larvae feed into the core, causing fruit abscission instead of just cosmetic injury. If you\u2019ve had a history of EAS and show a high population on traps, that one may be worth treating. However, if bloom is short, a petal fall application may be preferable.<\/p>\n

I am making all of these caveats because of the concern for impacts of spraying on wild and managed pollinators. Dr. Rufus Isaacs at Michigan state University recently posted a good summary<\/a> of consideration in reducing risk of pesticide impact on pollinators, which I summarize here but you can follow the link to read in full:<\/p>\n

\u00b7 Use integrated pest management (IPM) to reduce the need for sprays.<\/p>\n

\u00b7 Avoid pesticide sprays during crop bloom.<\/p>\n

\u00b7 Apply pesticides after sunset or before sunrise, or when air temperature is below 50\u00b0F.<\/p>\n

\u00b7 Select the least toxic pesticides and formulations when possible.<\/p>\n

\u00b7 Reduce drift onto areas outside crop fields.<\/p>\n

\u00b7 Remove flowering weeds from crops.<\/p>\n

\u00b7 Provide bee-friendly habitat away from crops.<\/p>\n

\u00b7 Develop and implement a pollination contract with your beekeeper.<\/p>\n

That last one should remind everyone that it\u2019s time to get our bees lined up if you\u2019re planning to rent hives. My old mentor Lorraine Berkett used to have us make bets on when the first McIntosh blossom would open in South Burlington. This year, I\u2019m guessing May 11.<\/p>\n

Where trade names or commercial products are used for identification,<\/p>\n

no discrimination is intended and no endorsement is implied.<\/p>\n

Always read the label before using any pesticide.<\/p>\n

The label is the legal document for the product use.<\/p>\n

Disregard any information in this message if it is in conflict with the<\/p>\n

label.<\/p>\n

The UVM Tree Fruit and Viticulture Program is supported by the<\/p>\n

University of Vermont Agriculture Experiment Station, a USDA NIFA E-IPM<\/p>\n

Grant, and USDA Risk Management Agency Funds.<\/p>\n","protected":false},"excerpt":{"rendered":"

By Terence Bradshaw Apple buds are rapidly expanding into tight cluster bud stage in most of Vermont, which sets the calendar close to \u2018normal\u2019 after the cool, slow start to the season. Apple scab infection periods have been somewhat scarce, depending on when you started you clock for ascospore maturity (green tip, minus any confidence … Continue reading Apple crop management this week<\/span><\/a><\/p>\n","protected":false},"author":2068,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[],"tags":[36708,107009],"class_list":["post-1068","post","type-post","status-publish","format-standard","hentry","tag-ipm","tag-tree-fruit"],"jetpack_publicize_connections":[],"featured_image_src":null,"featured_image_src_square":null,"author_info":{"display_name":"fruit","author_link":"https:\/\/blog.uvm.edu\/fruit\/author\/fruit\/"},"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/p4nZlV-he","_links":{"self":[{"href":"https:\/\/blog.uvm.edu\/fruit\/wp-json\/wp\/v2\/posts\/1068","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.uvm.edu\/fruit\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.uvm.edu\/fruit\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.uvm.edu\/fruit\/wp-json\/wp\/v2\/users\/2068"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.uvm.edu\/fruit\/wp-json\/wp\/v2\/comments?post=1068"}],"version-history":[{"count":0,"href":"https:\/\/blog.uvm.edu\/fruit\/wp-json\/wp\/v2\/posts\/1068\/revisions"}],"wp:attachment":[{"href":"https:\/\/blog.uvm.edu\/fruit\/wp-json\/wp\/v2\/media?parent=1068"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.uvm.edu\/fruit\/wp-json\/wp\/v2\/categories?post=1068"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.uvm.edu\/fruit\/wp-json\/wp\/v2\/tags?post=1068"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}