March 23, 2020 VOLUME 29, No. 1 Geneva, NY

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IN THIS ISSUE...GENERAL INFO v New year of Scaffolds intro v References & Resources v Webinar : Bloom Thinning with Pollen Tube Growth ModelDISEASES v Early season disease mgt in 2020 v Spring clean-up for orchardsHORTICULTURE Herbicide resistance screening in 2020 INSECTS v Black stem borer surveyCHEM NEWS v Product registration update

PEST FOCUSUPCOMING PEST EVENTS

GENERAL

INFO

scaffoldsF R U I T J O U R N A L

Update on Pest Managementand Crop Development

convinced me to change my major to biolo-gy, and I took advantage of as many en-

tomology courses as I could cram into my final two years of college. I never had a clue where it might eventually take me, but I was never unsure of the import of these quasi-aliens to

my professional curiosity and even-tual career plans. As it happened, my

childhood dread of the bee's sting finally evolved into a determination to derail many of their other behaviors, all related to fruits and the trees they grow on. If only I still had that magni-fying glass. vv

Now Streaming Online – Suitable for binge-read-ing Actually, not really. But Scaffolds will con-tinue to be available via email and online this year;

MITES ARE FROMMARS,BEES AREFROM

VENUSArt Agnello (Entomology, Geneva; ama4@cornell.edu)

vv Insects were never something I was especially interested in when I was growing up. My neighborhood pals and I used to enjoy frying ants with a magnifying glass, and I recall being in dread fear of all stinging insects, but aside from that they weren't of much interest compared with the important things like bikes and baseball. Still, I couldn't help noticing how strange insects were, with their green bodies and long antennae, like the aliens depicted in Satur-day morning cartoons. Herb Kramer, my biolo-gy teacher at East High, revealed one day that he had studied entomology in grad school, show-ing me his collection of neatly pinned insects, with its compelling assortment of sizes, shapes and colors that was difficult not to appreciate and preserve in memory.

Later, as a freshman at Cornell, and ostensi-bly a chemistry major, I made fast friends with a guy in my dorm who was in the Ag School and convinced me (plus half the others on our corridor) to take a popular beekeeping course from Roger Morse – never mind our professed disinterest in bees – simply for the experience of learning from one of the world's authorities on this novel topic, and who was furthermore an inspired and entertaining lecturer. Although this adventure didn't persuade me to take up beekeeping, the startling exposure it provided to a remarkable group of organisms ultimately

SMALL WONDERS

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scaffoldsis published weekly from March to September by Cornell University—Cornell AgriTech at the NYS Agricultural Ex-periment Station (Geneva) and Ithaca—with the assistance of Cornell Cooperative Extension. New York field reports welcomed. Send submissions by 2 pm Monday to:

scaffolds FRUIT JOURNAL Dept. of Entomology Cornell AgriTech at NYSAES 15 Castle Creek Dr. Geneva, NY 14456-1371 Phone: 315-787-2341 FAX: 315-787-2326 E-mail: ama4@cornell.edu

Editor: Art Agnello

This newsletter available online at: http://www.scaffolds.entomology.cornell.edu/

no account sign-in required. As always, we ask subscribers to inform us of any address changes, so that we don't clog up the bandwidth with unde-liverable messages that end up lost in the cloud.

Scaffolds is sent as a pdf file via email each Monday afternoon. For those desiring a more screen-friendly format than the double column we currently use, I can send an unformatted plain text version to anyone who requests it, in addition to (or in place of) the pdf. There is also a web version available, which should be up and ready for viewing at the same time as the emailed pdf is sent. Scaffolds can be found online at: http://www.scaffolds.entomology.cornell.edu/. Please make a note of this address in any bookmarks you may maintain that point to Scaffolds.

Also, we will post a version of Scaffolds on-line that is formatted to be more easily read on smartphones and other mobile devices. Look for "ScaffoldsMD for Mobile Devices" under the cur-rent link to the PDF version.

As always, we are happy to consider contribu-tions (particularly from NY sources) in the form of articles on topics in any of the fruit crop protection or production areas, as well as NY field observa-tions, trap data, etc. Our preferred deadline for such communiqués is 2 p.m. on Monday. vv

REFERENCES, RESOURCES

2020 Cornell Pest Management Guidelines for Commercial Tree Fruit Production Please note that these guidelines are available from the Cornell Store, both in a printed book for-mat as well as online once again; however, the on-line version is not free, but must be purchased (for $41.00, the same price as the print version). There is also a bundle option, which provides both for 40% more than the cost of either version alone. If you do not receive the Tree Fruit Guidelines as part of your membership in a county-based CCE fruit program, visit https://www.cornellstore.com/books/cornell-cooperative-ext-pmep-guidelines for purchasing details.

ADDENDA • Baythroid XL (Bayer CropScience, EPA Reg. No. 264-840) should be added to the list of products having a FIFRA 2(ee) registration against spotted wing drosophila in pome and stone fruits. The label should be in the possession of the user at the time of application. • Cidetrak CMDA Combo Meso-A (Trécé, EPA Reg. No. 51934-16), a meso pheromone product labeled for mating disruption of codling moth, was inadvertently omitted from the list of options in the Pesticide Spray Tables for Apples and Pears, due to a production error in the publica-tion software.

Stone Fruit IPM for Beginners This recently released booklet, developed by the Great Lakes Fruit Workers, is a series of how-to fact sheets for new stone fruit growers and scouts to protect stone fruit orchards from pests. Editors and authors include Julianna Wilson, MSU; Juliet Carroll, Cornell; Emily Pochubay, MSU; Arthur Agnello, Cornell; and William Shane, MSU. This guide is available online and can be downloaded as individual chapters or as an entire publication, at: https://www.canr.msu.edu/ipm/agriculture/fruit/stone-fruit-ipm-for-beginners

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EARLY SEASONDISEASE MANAGEMENTIN 2020

(Kerik Cox & Katrin Ayer, Plant Pathology & PMB, Geneva; kdc33@cornell.edu & kma86@cornell.edu)

vv The weather was cold in late October, but became warm from November to early January. Fortunately, it was consistently be-low freezing until the end of February. We had snowstorms but didn't have consistent snow cover as was commonplace five to ten years ago. Nowadays, snow only comes in as lake effect or in the form of larger nationwide storms that pass through NY. In the Hudson Valley and Long Island, green tip is imminent or under way for the early varieties, and mature ascospores have been detected. The rest of the production areas of the state could reach green tip in a few weeks. In the coming week, there are cooler days forecasted, which could slow tree development. Overall, the season will be upon us shortly, and we need to consider early season management for apple scab and other diseases. In 2019, many areas of the state had considerable rainfall from late May through June, which exceeded 10 inches and included more than 15 infection periods from April to August. Rains were adequately spaced, af-fording growers the opportunity to keep trees protected and successfully manage apple scab. Indeed, we received no reports of apple scab control failures in conventionally managed or-chards.

Because of the 2019 season rains, consid-erable overwintering inoculum for apple scab and summer diseases might be present despite the appearance of clean trees at harvest and clean fruit in storage. As fruit comes out of storage, presence of rots and pinpoint scab may also indicate late-season buildup of orchard in-oculum. Hence, taking steps to reduce orchard

BUD'S-EYE VIEW

floor litter may greatly reduce the inoculum for apple scab, other foliar diseases like Marsson-ina leaf spot, and fruit rot diseases in the com-ing season. As soon as it is possible to enter the orchard (soils seem dry in Geneva), remove any remaining fruit drops and pruned shoots left on the floor from winter pruning that may con-tain bitter rot or black rot inoculum. If apple scab leaf inoculum reduction was not practiced in the fall with flail mowing or urea sprays, it will be important to practice inoculum reduc-tion this spring. Even if the planting is in green tip, inoculum reduction may still provide some benefit by reducing inoculum pressure by tight cluster or pink, when tissues are at their greatest susceptibility to apple scab.

The two best options for inoculum reduction are to shred leaves with a flail mower or treat the leaf litter with an application of urea. In the case of flail mowing, leaves should be swept or raked from underneath the canopy into row middles. Subsequently, go over the row middles with the flail mower set to scalp the sod. If urea is used, applications should be made at 40 lbs of feed grade urea per acre in 100 gallons of water. Dolomitic lime can be used instead, applied at a rate of 2.5 tons per acre. Of the various options, applying urea is the simplest approach, but take care to flush the sprayer pumps with water after-wards since the urea is caustic and can corrode a pump over time. As suggested above, the use of orchard floor urea may also reduce inoculum of other diseases (e.g., Marssonina blight, Bitter rot, and Black rot) as it hastens decomposition of leaf litter and old fruit drops. The application of urea on the orchard floor will also enhance the decay of any plant organic matter, includ-ing fruit drops and pruned shoots, that harbor the pathogens causing summer cankers and fruit rots.

The conditions for fire blight development were favorable in 2019, but it wasn't a devastat-ing fire blight season for NY. However, a "de-layed-dormant" application of copper at silver

DISEASES

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tip will help reduce inoculum for both apple scab in buds and fire blight in cankers for or-chards with problems in 2019. As the weather begins to warm (>60°F) in the coming weeks, fire blight cankers could begin to ooze; be on the lookout for these. While we had some peri-ods of warm weather in January and February, overwintering cankers are still dormant at Cor-nell AgriTech as of 3-20-20. These are high-in-oculum fire blight research orchards and there is still no sign of oozing. It's important to note that cold weather will not kill fire blight bacte-ria overwintering in cankers. The bacteria will remain viable at low (<32ºF) temperatures. By the time we reach bud break, cankers could be oozing. To reduce early season apple scab and fire blight inoculum, make the "delayed dor-mant" silver-tip application of a high (>15%) metallic copper equivalent (MCE) copper fun-gicide (e.g., Badge, Kocide, Cuprofix). The early season may prove to be dry, and it might be easy to make this application. Even at green tip, it is generally still safe to apply high MCE copper products. In the Geneva research or-chards, our second application at 1/2-inch green is still often copper.

Once green tip is reached, it's advisable to start applying protectant fungicides for ap-ple scab, timed according to infection events predicted by weather conditions. If the buds are approaching 1/4-inch green, then one may wish to use a program of Captan with Manco-zeb at half maximal rates. The combination is referred as "Captozeb" in the vernacular sense. The combination has good protectant and redistribution properties, but has little to no post-infection activity, and must be applied before rains. Re-application is warranted when unprotected tissues emerge or when consider-able rainfall (>1") occurs.

It is advisable to use the NEWA apple scab forecasting system (http://newa.cornell.edu/in-dex.php?page=apple-diseases) or other disease forecasting services to identify predicted asco-

spore releases and potential infection events to improve application timing. When practi-cal, one should apply fungicides to get the best coverage prior to predicted large releases of ascospores (>15% discharge) during weather conditions conducive to infection.

Fig. 1. Output from the NEWA apple scab disease forecasting tool for early May in the Hudson Valley. An ideal time for protecting the crop with a fungicide would be before the predicted massive ascospore discharge on 5/3. The date of 5/1 would also be an ideal time for selecting a single-site fungicide over a pro-tectant fungicide, which has little to no post-in-fection activity. Such an application would also protect against the minor infection on 4/30 (3% ascospore discharge) and subsequent in-fections in early May. As the season approaches bloom or if there is rain for several days after green tip, consider some of the modern single-site fungicides (e.g., Luna Tranquility, Luna Sensation, Flint, Fonte-lis, Merivon, Syllit, Rally, Rhyme, Inspire Su-per, Miravis, Aprovia). Many of the single-site fungicides will provide a broader range of activ-ity against other fungal pathogens like powdery mildew and fruit rots, which may cause latent infections at bloom, whereas the "Captozeb" combination does not. Given fungicide resis-tance concerns, it's no longer recommended to

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apply single-site fungicides for post-infection activity. Instead, think of making applications of single-site fungicides between infection pe-riods. Use disease forecasting to identify peri-ods where substantial ascospore release (>15% discharge) has occurred and another infection period is predicted soon after (Fig. 1).

For example, apply your selected sin-gle-site fungicide (with 3 lb/A mancozeb) for "next week's" infection within 24–48 hours af-ter the last infection period. It should protect against the next predicted infection and per-haps afford some curative activity if any ger-minating spores slipped through the fungicide coverage from the previous week. Of the sin-gle-site materials available, dodine, sold as Syl-lit, will likely be your strongest performer for applications between infection periods. How-ever, Syllit may only be applied twice before pink. Another option would be to use Aprovia, Miravis, Sercadis, Luna Tranquility or Inspire Super. The former three products are excep-tionally effective on apple scab, while the latter two are also highly effective, and include an anilinopyrimidine (AP), which works best in the colder temperatures that often occur prior to bloom. As the season progresses into bloom, Luna Sensation or Merivon, which contain qui-none outside inhibitor (QoI) fungicides, would be good choices for orchards planted along the lake where apple powdery mildew pressure can be high.

Summary A strong early disease management pro-gram should begin with an application of cop-per at bud break, "silver tip" to early green tip. This application will help reduce overwintering apple scab and fire blight inoculum and pro-tect against early season apple scab infections. Orchard floor inoculum reduction should be practiced as soon as orchards can be entered. This is accomplished by sweeping the orchard to remove prunings and any remaining apple

drops, which may harbor inoculum from many fungal pathogens. After sweeping, apply urea to degrade overwintering leaf litter to reduce apple scab inoculum and any other plant de-bris not removed by sweeping. From green tip to bloom, a program of protectant fungicides centering around captan and mancozeb should be implemented to protect the developing fruit clusters. If there are prolonged wetting periods in the early season, an application that includes mancozeb along with either Aprovia, Miravis, Sercadis, Syllit, Luna Tranquility, or Inspire Super may be helpful. As we proceed toward bloom, additional applications of single-site fungicides (e.g., Luna Sensation, Merivon) may be needed to manage powdery mildew and other fungal diseases that may begin as latent infections during bloom. Keep track of apple scab ascospore discharge and infection events predicted from local weather on the dis-ease forecasting service of your choice. vv

SPRING CLEAN-UP FOR ORCHARDS(Dave Rosenberger,Plant Pathology,Highland;

dar22@cornell.edu)

vv Attention to a few disease-control de-tails in early spring can make life easier through the rest of the summer. Following is my list of reminders:

For Apple Scab and Marssonina In blocks or around trees where these dis-eases were a problem last year, disease control this year will be much easier if overwintering leaves can be removed, shredded with a mow-er, or sprayed with urea prior to bud break. The latter two approaches will speed decay of the leaves, thereby destroying the overwintering phases of the fungi before the full comple-ment of spores can be released. Details for

SANITIZINGMEASURES

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these processes have been described elsewhere (Rosenberger 2005; Acimovic 2020). Where neither of these diseases were a problem last year, there is no reason to spend extra time and money on managing leaf litter.

For Fire Blight Where fire blight was a problem last year, all diseased twigs, branches, and cankers should have been removed during winter prun-ing. The pathogen in winter prunings will lose viability as the prunings dry out. So far as we know, there is no risk of spreading the pathogen by shredding the prunings with a flail mower. After winter pruning to remove can-kers, the next line of defense is provided by a copper spray applied at silver tip or green tip. The preponderance of evidence suggests that new low-rate coppers provide relatively short residual activity on trees (Rosenberger et al. 2013). For the silver tip spray, we generally suggest copper products that can be applied at rates that will result in application of at least 2 lb of elemental copper per acre, thereby pro-viding more extended protection. In years with a late spring when trees are expected to progress rapidly from green tip to tight cluster, using lower rates of copper may help to reduce the risk of fruit russetting that can occur if cop-per residues persist too long and injure tissue at the base of flower buds that later develops into fruit. However, weather so far this year suggests that we may have a more drawn-out spring where higher rates of copper will prove beneficial for controlling fire blight in problem blocks. In blocks where no fire blight has been found in either of the past two years, there is little if any reason to apply copper. Copper is used to suppress bacteria emerging from ob-scure infections that remain in the orchard af-ter pruning. If there has been no evidence of fire blight for two years, then presumably there are no active blight infections and therefore no targets for the copper sprays in apples or pears.

For Bitter Rot In blocks where bitter rot was a problem last year, remove all fallen fruit, fruit mummies, and pruned twigs from beneath trees and either dispose of them away from the orchard or flail-chop them in row middles to break them down for more rapid decay. Rotted fruit left on the orchard floor over winter have been recognized as inoculum sources since 1903 (Schrenk and Spaulding 1903; also see commentary at http://blogs.cornell.edu/plantpathhvl/apple-diseases/summer-diseases/bitter-rot/). Twigs pruned from trees last summer or this spring can be colonized by the bitter rot pathogens (Fig. 2). Those colonized twigs may produce inoculum for fruit decay in summer.

Fig. 2. Pruned twigs haboring decay fungi.

For Crab Apple Pollenizer Trees Where crab apples are used to enhance cross-pollination, any cankers in the crab apple trees should be removed during summer prun-ing. In Washington State, cankers on crab ap-ple pollenizer trees have been identified as the inoculum sources for several important post-harvest pathogens of apples and pears (Xiao et al. 2014). The diseases identified on the west coast are not very common as postharvest pathogens in eastern apple orchards, perhaps because those diseases are suppressed by the extensive summer fungicide programs that we must employ to protect fruit from flyspeck and

continued...

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other summer fruit rots. Nevertheless, it is un-wise to allow fungal cankers to persist within orchards, even if they are found only on pol-lenizer trees.

Black knot For those growing plums and tart cherries, any black knots (Fig. 3) found in trees should be pruned out before trees reach the white bud stage by cutting at least 8 inches below the ex-isting knot. The knots that are removed should be either burned immediately, buried, or bagged for disposal with other trash that is sent to a landfill. Do NOT dispose of the pruned-out knots in a hedgerow beside your orchard: Spores from the prunings will blow back into the orchard and cause new infections. (Even though I should have known this, I learned it the hard way in a research block many years ago!) Removing black knots from infected trees is the primary method for controlling this disease. Fungicides applied during bloom will NOT protect trees when there is an abundance of inoculum from knots that were not removed during winter.

Fig. 3. Black knot in a plum tree at bud break.

Peach Leaf Curl Peach leaf curl (Fig. 4) is relatively easy to control using copper sprays or one of the la-beled fungicides that are listed in Cornell's Pest Management Guidelines for Commercial Tree Fruit Production. Applications can be made during leaf drop in autumn or at bud swell in spring. If the peach crop was frozen out last year and no brown rot fungicides were applied to protect fruit last summer, then trees may be more prone to leaf curl this year. It seems that fungicides applied during summer to control brown rot reduce survival of leaf curl during summer and thereby reduce disease pressure for the following year. Summer fungicides alone are not enough; they must still be supplement-ed with either the leaf fall or the swollen bud application recommended for controlling peach leaf curl. Nevertheless, leaf curl disasters in the Hudson Valley have often been associated with orchards where the leaf curl spray was omitted or mis-timed in a year following a frozen-out crop.

Fig. 4. Peach leaves deformed by peach leaf curl.

Leaf curl sprays in spring should not be ap-plied before buds are swollen because the leaf curl fungus overwinters in the buds and fun-

continued...

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gicides applied to fully dormant buds can be washed off before the buds swell enough to al-low the fungicide to contact the overwintering fungus. Leaf curl sprays applied after buds have opened may be less than 100% effective, but applying a leaf curl spray a bit late is better than not applying any control at all.

For all of the above: "A stitch in time saves nine." Stopping or slowing diseases be-fore they get started is much easier and more cost-effective than trying to stop them after they begin to spread. For an apt illustration, check your local news feed for commentary on the coronavirus. vv

Note on active links: Some of the links in this article do not work correctly when clicked. You can get around this formatting issue by copying and pasting the URL link directly into your browser. Sorry for the inconvenience.

Literature citedAćimović, S.G. 2020. Reduce Inoculum of

Overwintering Fungi in Apple Leaf Litter: Marssonina coronaria & Venturia inaequa-lis.

Rosenberger, D.A., Rugh, A.L., Feldman, P.M., and Truncali, D.N. 2013. Compar-ison of copper products applied at green hip to control fire blight on apples. Pag-es 7–10 in blogs.cornell.edu/dist/d/3767/files/2013/11/2013-HVL-Field-trial-data-compr-203ay9s.pdf

Rosenberger, D.A. 2005. Jump starting apple scab control programs in high-inoculum or-chards. Scaffolds Fruit Journal 14(1): 3–5. http://www.scaffolds.entomology.cornell.edu/2005/050321.html#disease

Schrenk, H.V. and Spaulding, P. 1903. The bitter rot of apples. USDA Bureau of Plant Industries Bull. 41. 63 pp. https:// blogs.cornell.edu/dist/d/3767/files/2017/02/Shrenk-and-Spaulding-1903b-Bitter-rot-of-apple-18k8awc.pdf

HORTICULTURE

MEETINGWITH

RESISTANCE

STATEWIDE HERBICIDE RESISTANCE SCREENING TOSTART IN 2020:HELP US TO HELP YOU!

(Lynn Sosnoskie, Horticulture, Geneva;lms438@cornell.edu)

vv Weeds compete with crops for light, water, and nutrients, which can result in yield reductions. Weeds can also interfere with crop production by serving as alternate hosts for pests and pathogens, providing habitat for ro-dents, and impeding harvest operations. Con-sequently, growers employ a variety of control strategies, including the application of her-bicides, to manage unwanted vegetation. Al-though herbicides can be extremely effective at controlling undesirable plants, failures can and do occur. Weeds may escape chemical treat-ments for many reasons including the evolution of herbicide resistance.

Worldwide, there are 512 confirmed cas-es (species x site of action) of herbicide re-sistance (Fig. 5). With respect to the United States, 165 unique instances of resistance have been documented. In New York, there are only four formally reported occurrences; these in-clude common lambsquarters (Chenopodium album), smooth pigweed (Amaranthus hybri-dus), common ragweed (Ambrosia artemisiifo-lia) and common groundsel (Senecio vulgaris). All were described as being insensitive to the photosystem II inhibitors (e.g., atrazine and si-mazine).

Xiao, C.L., Kim, Y.K., and Boal, R.J. 2014. Sources and availability of inoculum and sea-sonal survival of Sphaeropsis pyriputrescens in apple orchards. Plant Dis. 98:1043–1049. (Note: color photos in the middle of the article are useful: https://apsjournals.apsnet.org/doi/pdf/10.1094/PDIS-12-13-1218-RE)

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I N S E C T S

BLACK STEM BORER SURVEY

Black stem borer is a destructive pest of apple trees that is becoming more problemat-ic around New York and other eastern states, particularly in high-density dwarf plantings. We are working with a regional IPM Working Group (based in Georgia) focused on these am-brosia beetles to gain a better understanding of

This, however, does not reflect the current on-the-ground situation in the state; work done by Drs. Julie Kikkert (CCE) and Robin Bell-inder (Cornell) indicates resistance to linuron in some populations of Powell amaranth (Am-aranthus powelli). Recent studies by Drs. Bry-an Brown (NYS IPM) and Antonio DiTomma-so (Cornell) suggest that horseweed (Conyza canadensis) and waterhemp (Amaranthus tu-berculatus) populations may be resistant to one or more herbicide active ingredients. Penn-sylvania has nine reported cases of herbicide resistance including glyphosate resistance in Palmer amaranth (Amaranthus palmeri), which was recently identified here in NY. While it is tempting to believe that herbicide resistance is a hallmark of agronomic cropping systems, resistance can and has developed in orchards, vineyards, vegetable crops, pastures, and along roadsides.

Beginning in 2020, we will undertake a screening effort to describe the distribution of herbicide resistance in the state. This coming summer and fall, growers, crop consultants and allied industry personnel who suspect they have herbicide resistance are encouraged to contact Dr. Lynn Sosnoskie (lms438@cornell.edu, 315-787-2231) to arrange for weed seed collection. Indicators of possible herbicide re-sistance include:• Dead weeds intermixed with live plants of the

same species.• A weed patch that occurs in the same place

and continues to expand, yearly.• A field where many weed species are con-

trolled but a previously susceptible species is not.

• Reduced weed control that cannot be ex-plained by skips, nozzle clogs, weather events, herbicide rate or adjuvant selection, and calibration or application issues.

Growers can take several actions to stop the spread of herbicide-resistant weeds and to

prevent the development of new ones. First and foremost is scouting fields following her-bicide applications and keeping careful records of herbicide performance to quickly identi-fy weed control failure. Pesticide applicators should ensure that their equipment is properly calibrated and that they are applying effective herbicides at appropriate rates to manage the target species. Whenever possible, diversify herbicides to reduce chemical selection pres-sures that result from the repeated use of a single herbicide or site of action. If possible, incorporate physical and cultural weed control practices into a vegetation management plan. Be sure to control unwanted plants when they are small, and never allow escapes to set seed. Clean equipment to prevent seeds of herbi-cide-resistant weed species from moving be-tween infested and non-infested sites, and har-vest areas with suspected resistant populations, last. vv

continued...

Fig. 5. Current status of herbicide resistance, globally, over time according to the Interna-tional Survey of Herbicide Resistant Weeds

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their biology, behavior, and ultimately effec-tive management around the country, not only in apples, but also in other commodities such as nursery ornamentals, pecans, avocados, and forest/shade trees. We are making an online survey on Black Stem Borer ambrosia beetles available to document their impact, and to use in grant proposals to support further research on these pests. If you are having problems with this pest, we ask that you please fill it out to assist us in this effort; responses will be anonymous, and it should take no more than 5 minutes of your time. You can access the survey at: https://ugeorgia.ca1.qualtrics.com/jfe/form/SV_0ojFgygi2BFmQ1n

PRODUCT REGISTRATION UPDATE(Art Agnello, Entomology, Geneva; ama4@cornell.edu)

vv Following is a list of the changes we are aware of to the pesticides available for use in NY tree fruit crops for the 2020 growing season; expect more to follow on an irregular basis:

New Registrations • Virosoft CP4 (BioTEPP, EPA Reg. No. 72898-4) contains a new isolate of this Cydia pomonella granulosis virus, nominally target-ed against codling moth, that is additionally effective against oriental fruit moth. Regis-tered for use in both pome and stone fruits; low bee-poisoning hazard, OMRI certified.

• Verdepryn 100SL (ISK Biosciences, EPA Reg. No. 71512-34-88783 through Summit Agro; distributed by Helena) contains cy-claniliprole, a new member of the diamide group (IRAC 28) that includes Altacor and Exirel, that is effective against plum curcu-lio and European apple sawfly as well as the fruit-feeding leps such as codling moth, ori-

ental fruit moth, and OBLR. Additional pests on the label include pear psylla, white apple leafhopper, European corn borer, leafminers, other leafrollers, cherry fruit fly, spotted wing drosophila and Japanese beetle. Restricted use, labeled in pome and stone fruits; not for use in Nassau or Suffolk Counties; high bee-poison-ing hazard.

• Miravis (Syngenta, EPA Reg. No. 100-1601) contains a new SDHI fungicide Pydiflu-metofen, which is effective for apple scab and apple powdery mildew. It’s registered for use in both pome and stone fruits, and is allowed on Long Island.

Cancellations • Carpovirusine - (Arysta LifeScience, CM granulosis virus); NY registration has ended. • Dimethoate - (Drexel); the last remain-ing registration in NY tree fruits (e.g., against aphids in pears) has ended. • Kumulus DF (sulfur) - NY registration has ended. • Pyrenone - (Bayer, pyrethrins); NY regis-tration has ended.

Lors-ban? In December, Gov. Cuomo directed the NYS DEC to ban chlorpyrifos for any uses other than apple trunk sprays, which will be al-lowed through 2021. So far, the DEC needs to adopt in regulation the implementation of the ban; until that happens, it can still be used as currently labeled. vv

CHEM

NEWS

Highland: Redbanded Leafroller 1st catch 3/16Green Fruitworm 1st catch today, 3/23

PEST FOCUS

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UPCOMING PEST EVENTS (corrected)

43°F 45ºF 50°FCurrent DD* accumulations (Geneva 1/1–3/23): 72.3 55.0 26.0 (Geneva 1/1–3/23/2019): 32.1 23.0 8.3 (Geneva "Normal"): 59.5 45.8 22.3 (Geneva 1/1-3/30, predicted): 85.9 – 29.2 (Marlboro 1/1–3/23): 140.8 – 55.5 Coming Events: Ranges (Normal ±StDev):Green fruitworm 1st catch 49-145 12-66Pear psylla adults active 31-99 8-34Pear psylla 1st oviposition 40-126 11-53McIntosh silver tip 58-106 19-41McIntosh green tip 99-144 38-62

*all DDs Baskerville-Emin, B.E.

NOTE: Every effort has been made to provide correct, complete and up-to-date pesticide recommendations. Nevertheless, changes in pesticide regulations occur constantly, and human errors are possible. These recommendations are not a substitute for pesticide labelling. Please read the label before applying any pesticide.This material is based upon work supported by Smith Lever funds from the Cooperative State Research, Education, and Extension Service, U.S. Department of Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.

PHENOLOGIES

Geneva: Highland:Apple Apple(McIntosh, Red Delicious): silver tip (McIntosh): 48% green tip (Empire, Idared): silver tip (Ginger Gold): 81% green tipPear: early swollen bud (Red Delicious): 74% green tipTart Cherry, early swollen bud (Smoothie): 44% green tipSweet Cherry, Peach: swollen bud (Empire): 89% green tipPlum, Apricot: swollen bud (Honeycrisp): 77% green tip (Gala): 76% green tip Pear (Bartlett): 79% swollen bud (Bosc): 71% swollen bud Sweet Cherry 18% swollen bud Peach 48% swollen bud