APPLE & PEAR• Codlingmoth egg hatch is at it’s fastest right now, so

make sure fruit is protected. See table on page 4.

CHERRY• Clean up cherry trees of fruit or make one last spray to

reduce cherryfruitfly population.

PEACH/NECTARINE, APRICOT, PLUM• Peachtwigborer treatment for the second generation is

beginning.• Continue protecting trunks from greaterpeachtreeborer.

Tree Fruit IPM AdvisoryWeekly Orchard Pest Update, Utah State University Extension, July 26 , 2013

News/What to Watch For:

Keep peach and apple protected from internal caterpillars through harvest or until Sept. 15, whichever is earlierExamine apple fruits for damage caused by codling mothExamine peach twigs for shoot strikes caused by peach twig borer; if you see more than 3 per tree, a treatment is necessaryWatch fruit for small white “pimples” with a purple halo; this is San Jose scaleUpdated spray timing dates for codling moth and peach twig borer, pages 4-5

JUST THE BASICS

EXPANDED COVERAGE - Insect and Disease Information

APPLE & PEAR

Codling Moth Egg hatch of the second generation is at or entering the period when about 75% of all the eggs laid will hatch in a 2-week time period. So make sure the fruit is well-protected so you can have a good crop! This generation of egg hatch will end toward late August. In the warmer areas of northern Utah, a third generation “blends” into the second, with egg hatch beginning again just a few days later.

For all areas: you do not need to worry about codling moth entering the fruit after September 15.

Commercialtreatment options (and days between sprays):a few options are Assail (14), Altacor (14-21), Delegate (14), Imidan (14-21); for more information, see the Intermoun-tain Tree Fruit Production Guide

Residentialtreatment options (and days between sprays):Spectracide Triazicide (14), Ortho Max Flower, Fruit and Vegetable (10-14), Sevin (14), Bonide Fruit Tree Spray (14), Malathion (7), Monterey Spinosad (5-7)

: includes information for residential settings : includes information for commercial orchards

When checking fruit for injury, look at the calyx end and where two fruits are touching.

Page 2Utah Pests’ Tree Fruit Advisory, 07-26-13

Insect and Disease Information, continued from previous page

Woolly Apple Aphid

Woolly apple aphid colonies are increasing steadily, and are primarily found along twigs and on old pruning scars. This aphid also feeds on roots, causing galls to form, and reducing tree vigor and crop load. Heavy infestations can leave honey dew and cause sooty mold on fruit.

Commercialtreatment options:Ultor (8-9 oz/acre mixed with an adjuvant) or Diazinon; for more information, see the Intermountain Tree Fruit Produc-tion Guide

Pear Psylla

If you had not noticed feeding by pear psylla this spring, dam-age is evident now. They are active from spring to fall, and if left unchecked, can build to damaging levels. Not only do they excrete honeydew, but their feeding kills the plant tissue, leav-ing irregular blotchy patterns.

At this point in the growing season, adults, eggs, newly-hatched nymphs and old nymphs can be found. The best tim-ing for treatment is in spring, but if necessary, summer oil can

be applied (when temperatures are below 85-90°F for at least 4 hours after spraying; at a rate of 1% in water).

STONE FRUIT

Peach Twig BorerMost areas in northern Utah should have applied your cover spray for the second generation. Keep in mind that most products last around 14 days, so a second spray may be needed to last to harvest.

Growers with late peaches may need to watch for and pos-sibly treat a 3rd generation in late August. No protection is needed after September 15.

Greater Peachtree Borer

Trap catches for peachtree borer continue to be high, and are increasing week to week. Continue spraying the trunks at intervals (14 days for younger trees, 21-30 days for more mature trees), with your last treatment around September 15.

Commercialtreatment (and days between sprays):a few options are Lorsban (one spray only; do not touch foliage), Asana (21); products containing permethrin (21-30 days) Isomate-P mating disruption (all season); for more information, see the Intermountain Tree Fruit Production Guide

Residentialtreatment options (14-30 days between sprays):products labeled for peaches that contain permethrin or bifenthrin: Bonide Borer-Miner Killer, Enforcer Outdoor Insect Killer, Hi-Yield Broad Use Including Gardens; Lilly Miller Multi-Purpose Insect Spray

Western Cherry Fruit FlyResearch out of Michigan State University has shown that cherryfruitflyflightpeaksAFTERharvest,anduntreatedfruitleft on the trees can become infested. Their research also showsthatthemajorityoffliesinfestingtreesororchardsoriginate from within the site.

Page 3Utah Pests’ Tree Fruit Advisory, 07-26-13

Insect and Disease Information, continued from previous page

The bottom line is: untreated fruit that remain on the tree after harvest represent a source for infestation the following season.

MSU Entomologist Larry Gut, has shown that a post-harvest application of imidacloprid (Admire/Provado, or generics) withinsevendaysafterharvesthasthepotentialtoreduceflypopulations for the following year, especially in orchards with high post-harvest catches. Dimethoate plus 1% oil is another option.

Backyard growers should remove and destroy all fallen fruit, and if possible, pick your cherry trees clean to remove egg-layingsitesforlate-emergingfruitflies.Pleaseplayyourrolein keeping your trees clean of this pest that can devastate a commercial growers’ crop.

Walnut Husk FlyWalnuthuskflypeakemergencewilloccurinearlytomidAugust. Keep nuts protected until a month before harvest.

Black, Japanese, and English walnuts are all hosts for the husk fly.(Peacharealsosometimesattacked.)

Apple MaggotApplemaggotisrelatedtothecherryfruitflyandhuskfly.Itwas recently reported by an observant backyard plum grower in a Salt Lake City neighborhood. Although the name implies thatthispestattacksonlyapple,itisalsocommontofinditinwild and cultivated plums.

TheUtahDepartmentofAgricultureandFoodfirstdetectedapple maggot in 1985 with the discovery of some maggots on traps in abandoned and noncommercial cherry orchards in Utah County. They then initiated a trapping program in com-mercial orchards every year since. In 2012, 433 traps weremonitored during the growing season, catching 5 maggots.

Apple maggot is a serious pest to commercial growers in the eastern U.S., but so far, have not been a problem in Utah.

Most western states have a quarantine enacted for both cherryfruitflyandapplemaggot.Thatmeansthatanyfruitexported to another state must be 100% free of both pests.

Likecherryfruitfly,applemaggotoverwintersinthesoil.Itemerges from late June through August, laying eggs in host fruit, which include apple, cherry, plum, crabapple, peach, chokecherry, and hawthorn. Any infested fruit is rendered inedible.

Apple maggot is known to occur in wild plums in Utah, but rarely do we hear of infestations in cultivated fruit. Backyard growers in the SLC area should watch all host fruits for infes-tationbyapplemaggot.PleasereportanyfindingstotheUtahIPM Program, at marion.murray@usu.edu, or 435-797-0776.

Spray Timing Information - Codling Moth

Please check this table at each advisory as the information may change as the dates get closer. The forecasts use the average temperature for each site. Fruit should remain protected through each generation according to interval provided on your pesticide label.

Codling Moth, Second and Third Generations

Second generation egg hatch “period of greatest egg hatch” (from 1400-1700 degree days) is the time period where there is the greatest chance of a successful entry by codling moth, so be sure that fruit is well protected during this time. Egg hatch ends at 2100 DD. The third generation of codling moth egg hatch begins just a few days later, at 2180 DD. In general, keep fruit protected until September 15

SECOND GENERATION THIRD GEN.

County LocationStart of egg

hatchPeriod of greatest

egg hatchKeep fruit protect up

to this dateStart of egg

hatch

Box ElderPerry passed July 17 - 29 August 15 August 19Tremonton passed July 26 - August 6 August 24 August 28

CacheRiver Heights passed July 28 - August 11 September 1 September 6Smithfield passed July 29 - August 11 August 29 September 2

Carbon Price passed July 22 - August 5 August 27 September 2Davis Kaysville passed July 21 - August 1 August 17 August 21Grand Castle Valley passed passed passed July 19Iron Cedar City passed July 21 - August 4 August 21 August 25Juab Tintic passed August 2 - 16 September 15 ---

Salt LakeHolladay passed passed August 5 August 8Taylorsville passed passed August 6 August 9

Sevier Monroe passed July 17 - 29 August 18 August 22

TooeleErda passed July 19 - July 30 August 14 August 18Grantsville passed passed August 8 August 11

Uintah Vernal Airport passed July 22 - August 5 August 25 August 29

Utah

Alpine passed July 28 - August 10 August 28 September 1American Fork passed July 22 - August 3 August 19 August 23Genola passed July 19 - 31 August 16 August 20Lincoln Point passed July 20 - August 1 August 16 August 20Orem passed July 21 - August 1 August 17 August 20Payson passed July 22 - August 3 August 19 August 22Provo passed July 18 - 29 August 13 August 16Santaquin passed July 21 - August 2 August 18 August 22Tickville passed July 29 - August 13 September 15 ---West Mountain passed July 26 - August 7 August 23 August 26

Weber Pleasant View passed July 18 - 29 August 13 August 16Wasatch Heber City July 26 August 9 - 27 September 15 ---Wayne Torrey passed July 9 -21 August 7 August 12

Page 4Utah Pests’ Tree Fruit Advisory, 07-26-13

Page 5Utah Pests’ Tree Fruit Advisory, 07-26-13

Spray Timing - Peach Twig Borer

Peach Twig Borer, Second and Third GenerationsForthestartofsecondgenerationegghatch,selectthedatethatbestreflectstheinjurylevelyouhadlastyear(earlierformoreinjury,andlaterforless).Thesedatescorrespondto1200and1300degreedaysafterbiofix,or5%and16%egghatch.Theendofegg hatch for the second generation, where you should “keep fruit protected up to” is at 1900 degree days. Most will not need to worry about a 3rd generation (10% egg hatch at 2200 DD) but if you have late peaches, you may need to.

SECOND GENERATION THIRD GEN.

County LocationStart Date

(high population)Start Date

(low population)Keep Fruit

Protected Up To: Start Date

Box ElderPerry July 20 July 25 August 15 August 29Tremonton July 27 July 31 August 21 September 5

Cache All Locations August 7 August 11 September 15 noneCarbon Price July 29 August 3 September 9 noneDavis Kaysville July 20 July 24 August 15 August 28Grand Castle Valley passed passed passed July 25Iron Cedar City July 23 July 27 August 21 September 6Juab Tintic August 4 August 8 September 11 none

Salt LakeHolladay July 14 July 18 August 7 August 17Taylorsville July 14 July 17 August 6 August 17

Sevier Monroe July 18 July 22 August 17 September 3

TooeleErda July 19 July 23 August 11 August 23Grantsville July 17 July 21 August 8 August 20

Uintah Vernal July 28 August 2 September 2 none

Utah

Alpine July 28 August 2 August 28 noneAmerican Fork July 20 July 24 August 16 August 30Genola July 19 July 21 August 15 August 28Lincoln Point July 22 July 26 August 18 September 1Orem July 22 July 26 August 18 August 31Payson July 21 July 24 August 16 August 30Provo July 18 July 24 August 12 August 24Santaquin July 21 July 25 August 17 August 31Tickville July 31 August 6 September 5 noneWest Mountain July 23 July 26 August 21 September 5

Weber Pleasant View July 19 July 23 August 13 August 25Wayne Torrey July 6 July 10 August 10 August 25

UtahStateUniversityisanaffirmativeaction/equalopportunityinstitution.

Precautionary Statement: Utah State University Extension and its employ-ees are not responsible for the use, misuse, or damage caused by application or misapplication of products or information mentioned in this document. All pesticides are labeled with ingredients, instructions, and risks. The pesticide ap-plicator is legally responsible for proper use. USU makes no endorsement of the products listed herein.

Tree Fruit IPM Advisoryis published weekly by Utah State University Extension

Editor: Marion Murray, marion.murray@usu.edu

click here for archived advisories

Page 6Utah Pests’ Tree Fruit Advisory, 07-26-13

Spray Materials - Residential ApplicatorsNotethatthesetreatmentsareonlyrecommendedifyouknowyouhavetheparticularpestinyourtrees.Werecom-mendlearningaboutspecificpests,andscoutingyourtreesatleastonce/week.

Target Pest Host Chemical Example Brands CommentsCodling moth

apple, pear

Conventionalacetamipridcarbarylmalathiongamma-cyhalothrin

Soft/organichort. oil (1%)spinosad

codling moth virus

Ortho Flower, Fruit, and Veg.Sevin, Bonide Fruit Tree Spray, etc.MalathionSpectracide Triazicide

Many productsGreen Light Lawn and Garden Spinosad; Gardens Alive Bull’s Eye; Ferti-Lome Borer, Bagworm, Leafminer & Tent Caterpillar; Monterey Garden Insect Spray; Cyd-X

acetamiprid: every 14 dayscarbaryl: every 14 daysmalathion: every 7 daysgamma-cyhalothrin: every 14 dayshort. oil: lasts 5-7 days for killing eggs;

use at beginning of each generation; ap-ply at 1% rate only when temperatures are below 80; follow up with a different product

spinosad: every 7 dayscodling moth virus can only be pur-

chased online; Peaceful Valley Farm Supply

Greater peachtree borer

peach, nectarine, apricot

permethrin, bifenthrin, or gamma-cyhalothrin

Bonide Borer-Miner Killer, Hi-Yield Indoor/Outdoor Broad Use; Lilly Miller Multi-Purpose Insect Spray, Spectracide Triazi-cide

apply every 21 days until mid-September in highly infested areas; apply twice (now and one month later) in low infestations

Peach twig borer

peach, nectarine

Conventionalacetamipridcarbarylmalathionpermethrin

Soft/organicspinosadkaolin clay

Ortho Flower, Fruit & VegSevin, Bonide Fruit Tree Spray, etc.MalathionHi-Yield Indoor/Outdoor Broad Use; Lilly Miller Multi-Purpose Insect Spray

see ‘codling moth’ aboveSurround

see comments under Codling Moth

permethrin: every 14 days; this ingredi-ent is becoming less available in stores and may cause spider mite outbreaks

Surround: every 3-5 days; works to repel, not kill insects; only moderate control; must purchase online

Western cherry fruit flyandWal-nuthuskfly

cherry Conventionalacetamipridcarbarylmalathionpyrethrin

Soft/organicspinosad

Ortho Flower, Fruit & Veg.SevinMalathionConcern Multi-Purpose

see above

start applications when fruit in sunniest locations develop a salmon blush

spinosad: every 7 days