PEAR. UC IPM Pest Management Guidelines: Contents (Dates in parenthesis indicate when each topic was updated) June 2017.

Transcription

1 UC IPM Pest Management Guidelines: PEAR June 207 Contents (Dates in parenthesis indicate when each topic was updated) Pear Year-Round IPM Program (Reviewed /2)... iv General Information (Section reviewed /2)... Dormant to Delayed-Dormant Sampling (/2)... Pheromone Traps (/2)...3 Sampling at Bloom (/2)...4 Sampling During Fruit Development (/2)...5 Harvest Fruit Sample (/2)...7 Postharvest Survey (/2)...8 Relative Toxicities of Insecticides and Miticides Used in Pears to Natural Enemies and Honey Bees (/2)...9 General Properties of Fungicides Used in Pears (/2)... Fungicide and Bactericide Efficacy (6/7)...3 Most Effective Treatment Timings for Key Diseases (6/7)...6 Fungicide Resistance Management (6/7)...7 Insects and Mites (Section reviewed /2)...8 Aphids (/2)...8 Brown Mite (/2)...20 California Pear Sawfly (/2)...22 Codling Moth (/2)...23 Cutworms And Armyworms (/2)...3 European Red Mite (/2)...32 Fruittree Leafroller (/2)...35 Green Fruitworms (/2)...37 Italian Pear Scale (/2)...39 Katydids (/2)...40 Lygus Bugs (/2)...42 Mealybugs (/2)...44 Obliquebanded Leafroller (/2)...47 Omnivorous Leafroller (/2)...50 Orange Tortrix (/2)...52 Pear Cankerworms (/2)...54 Pear Psylla (/2)...55 Pear Rust Mite (/2)...60 Pear Sawfly (Pearslug) (/2)...63 Pearleaf Blister Mite (/2)...65 San Jose Scale (/2)...68 Stink Bugs And Other Plant Bugs (/2)...7 Thrips (/2)...74 Webspinning Spider Mites (/2)...76 Western Boxelder Bug (/2)...79 Diseases (Section reviewed /2)...8 Armillaria Root And Crown Rot (Oak Root Fungus) (/2)...8 Blossom Blast (/2)...83 Fire Blight (/2)...84 Pear Decline (/2)...88 Pear Scab (/2)...89 Weeds (Section reviewed /2)...95 An illustrated version of this guideline is available online at Publication 3455 Statewide Integrated Pest Management Program

2 Integrated Weed Management (/2)...95 Weed Management in Organic Orchards (/2)...99 Special Weed Problems (/2)...03 Common and Scientific Names of Weeds in Pear (/2)...06 Susceptibility of Spring and Summer Weeds in Pear to Herbicide Control (/2)...08 Susceptibility of Winter Weeds in Pear to Herbicide Control (/2)...0 Herbicide Treatment Table (/2)... Precautions for Using Pesticides...5 November 202 ii

3 Authors Insects and Mites: L. G. Varela, UC IPM Program, UC Cooperative Extension, Sonoma Co.; R. B. Elkins, UC Cooperative Extension,Lake Co.; R. A. Van Steenwyk, Insect Biology, UC Berkeley; C. Ingels, UC Cooperative Extension, Sacramento Co. Diseases: R. B. Elkins, UC Cooperative Extension, Lake Co.; W. D. Gubler, Plant Pathology, UC Davis; J. E. Adaskaveg, Plant Pathology, UC Riverside Weeds: R. B. Elkins, UC Cooperative Extension, Lake Co.; J. A. Roncoroni, UC Cooperative Extension, Napa Co.; C. A. Ingels, UC Cooperative Extension, Sacramento Co.; B. Hanson, Weed Science, UC Davis Crop Leadership Team: R. B. Elkins, UC Cooperative Extension, Lake County (crop team leader); L. G. Varela, UC IPM Program, UC Cooperative Extension, Sonoma County (IPM Facilitator); J. A. Roncoroni, UC Cooperative Extension, Napa County Acknowledgment for contributions to Insects and Mites: C. Pickel, UC IPM Program, UC Cooperative Extension, Sutter & Yuba counties; P. W. Weddle, Weddle, Hansen & Associates; R. Hansen, Weddle, Hansen & Associates; P. Chevalier, United Ag Products, Ukiah; M. Hooper, Ag Unlimited, Lakeport; B. Knispel, Pest Control Adviser, Upper Lake; T. Lidyoff, Purity Products, Healdsburg; G. McCosker, Harvey Lyman Agservices, Walnut Grove; B. Oldham, Ag Unlimited, Ukiah; J. Sisevich, AgroTech, Kelseyville (retired); D. Smith, Western Farm Service, Walnut Grove; B. Zoller, The Pear Doctor, Inc., Kelseyville Acknowledgment for contributions to Weeds: W. T. Lanini, Weed Science and Plant Sciences, UC Davis Acknowledgment for contributions to the year-round IPM program development: L. R. Wunderlich, UC Cooperative Extension, El Dorado Co. Acknowledgment for contributions to Crop Team and Year-Round IPM Program Development: L. R. Wunderlich, UC Cooperative Extension, El Dorado County About this publication Produced and edited by UC Statewide IPM Program University of California, Davis Guidelines Coordinator: T. A. Martin Production: F. Rosa This publication has been anonymously peer reviewed for technical accuracy by University of California scientists and other qualified professionals. This review process was managed by the ANR Associate Editor for Agricultural Pest Management. The UC IPM Pest Management Guidelines are available from: Online: UC Cooperative Extension County Offices University of California ANR Communication Services Richmond, CA ; Updates: These guidelines are updated regularly. Check with your University of California Cooperative Extension Office or the UC IPM Web site for information on updates. Note to readers: These guidelines represent the best information currently available to the authors for Bartlett pears grown in California and are intended to help you in making the best choices for an IPM program. Recommendations in this publication have not been validated for other varieties, including Asian pears. Not all registered materials or formulations are mentioned. Always read the label and check with local authorities for the most up-to-date information regarding registration and restrictions on pesticide use. Check with cannery field representatives before applications are made. Check the pesticide label for latest restricted entry intervals. To be used with UC ANR Publication 3340, Integrated Pest Management for Apples and Pears, 2nd edition November 202 iii

4 Pear Year-Round IPM Program (Reviewed /2) ANNUAL CHECKLIST Supplement to UC IPM Pest Management Guidelines These practices are recommended for a monitoring-based IPM program to reduce the risks of pesticides on the environment and human health. When a pesticide application is considered, review the Pesticide Application Checklist at the bottom of this page for information on how to minimize the risks of pesticide use to water and air quality. Water quality can be impaired when pesticides drift into waterways or move off-site. Air quality can be impaired when pesticide applications release volatile organic compounds (VOCs) into the atmosphere. This year-round IPM program covers the major pests of pear. Track your progress through the year with the annual checklist form. Details on carrying out each practice, example monitoring forms, and information on additional pests can be found in the Pear Pest Management Guidelines at ü Done Dormancy to delayed-dormancy Special issues of concern related to environmental quality: dormant sprays, drift, and runoff. Mitigate pesticide effects on air and water quality. Take beating tray samples for pear psylla adults. Examine dormant spurs for European red mite eggs Pear rust mite and pearleaf blister mite Pear psylla eggs if sampling in February Manage if needed according to the Pear Pest Management Guidelines. Also, note the presence of predatory mites. Examine shoots for San Jose scale and pear scab lesions. Look under bark for mealybugs. Manage orchard floor vegetation: North Coast: Eliminate weeds and ground cover before bloom in areas where frost and russeting are likely. Delta: Mow resident vegetation or cover crop before bloom. Monitor orchard temperatures and protect from frost, which can favor blossom blast. ü Done Bloom (red bud to petal fall) Special issues of concern related to environmental quality: drift, and runoff from rain. Mitigate pesticide effects on air and water quality. Examine flower clusters for: Pear psylla eggs and nymphs European red mites Pear rust mites Caterpillars (green fruitworm, obliquebanded leafroller) Western flower thrips Mealybugs (grape, obscure) Western boxelder bug eggs, nymphs, and adults Manage if needed according to the Pear Pest Management Guidelines. (/2) Pear Year-Round IPM Program Annual Checklist iv Download this form at

5 ü Done Bloom (red bud to petal fall) Special issues of concern related to environmental quality: drift, and runoff from rain. Mitigate pesticide effects on air and water quality. Place pheromone traps in the orchard for: Codling moth in late March for mating-disruption and conventional orchards Consperse stink bug in early April Obliquebanded leafroller in late April Check traps and keep records (example form available online). If using mating disruption for codling moth, place pheromone dispensers in orchard at biofix. When weather conditions promote disease, time fungicide and antibiotic treatments as needed according to the Pear Pest Management Guidelines. Pear scab Check leaves and emerging fruit for pear scab lesions 7 to 0 days after an infection period to assess the effectiveness of treatment. Fire blight Watch the orchard for vertebrates and manage as necessary: Gophers Ground squirrels Voles (at the base of young trees) In cold, wet weather note the presence of blossom blast. ü Done Fruit development (petal fall to harvest) Special issues of concern related to environmental quality: runoff from irrigation and drift. Mitigate pesticide effects on air and water quality. Take weekly samples. Examine leaves for: Aphids European red mites and eggs Katydids or feeding damage Pear psylla eggs and nymphs Pear sawfly (pearslug) eggs and larvae Pearleaf blister mite damage Twospotted spider mites and predatory mites Examine fruit for: Codling moth larva or damage Katydid damage after June 30 Mealybugs (grape, obscure) at the calyx Obliquebanded leafroller larva or damage Pear rust mites at the calyx Plant bug damage (western boxelder bug, lygus bugs, stink bugs) Manage if needed according to the Pear Pest Management Guidelines. Continue to monitor codling moth: Continue monitoring traps. Monitor fruit on the tree for damage at 800 to 900 degree-days from biofix. Check fallen fruit on the ground in early July. Manage if needed according to the Pear Pest Management Guidelines. Check cover crops and weeds for: Plant bugs (lygus bugs, stink bugs) Katydid nymphs Manage if needed according to the Pear Pest Management Guidelines. Continue monitoring weather conditions during rattail bloom for fire blight. (/2) Pear Year-Round IPM Program Annual Checklist v Download this form at

6 ü Done Fruit development (petal fall to harvest) Special issues of concern related to environmental quality: runoff from irrigation and drift. Mitigate pesticide effects on air and water quality. Manage orchard floor vegetation: Mow, cultivate, or apply a postemergence herbicide to manage ground cover. Survey for escaped winter weeds and emerging annual and perennial summer weeds. Keep records (example form available online). Note the presence of Armillaria root rot (oak root fungus). ü Done Harvest Check fruit for feeding damage caused by: Codling moth Katydids Mealybugs (grape, obscure) Obliquebanded leafroller Pearleaf blister mite Pear rust mite Pear scab lesions (primary or secondary) Plant bugs (western boxelder bug, lygus bugs, stink bugs) San Jose scale New or unusual damage or pests Continue checking codling moth traps through mid-september in mating-disruption and conventional orchards. ü Done Postharvest Mitigate pesticide effects on air and water quality. Check top shoots for Pear psylla nymphs and eggs Webspinning spider mites European red mite Pear rust mite Pearleaf blister mite damage on leaves Pear sawfly (pearslug) Pear scab lesions on leaves Sample fruit left on trees for codling moth and codling moth damage. Manage orchard floor vegetation: Survey winter annual weeds and keep records (example form available online). Manage weeds in rows with pre- or postemergence herbicides or nonchemically. Consider seeding a cover crop by mid-october. (/2) Pear Year-Round IPM Program Annual Checklist vi Download this form at

7 ü Done Pesticide application checklist When planning for possible pesticide applications in an IPM program, consult the Pest Management Guidelines, and review and complete this checklist to consider practices that minimize environmental and efficacy problems. ü Choose a pesticide from the Pest Management Guidelines for the target pest, considering: Impact on natural enemies and pollinators. For more information see Protecting Natural Enemies and Pollinators at Potential for water quality problems using the UC IPM WaterTox database.see Impact on aquatic invertebrates. For more information, see Pesticide Choice, UC ANR Publication 86 (PDF), Chemical mode of action, if pesticide resistance is an issue. For more information, see Herbicide Resistance: Definition and Management Strategies, UC ANR Publication 802 (PDF), Endangered species that may be near your site. Find out using the Department of Pesticide Regulation's PRESCRIBE program. ( ü Before an application Ensure that spray equipment is properly calibrated to deliver the desired pesticide amount for optimal coverage. (See Use appropriate spray nozzles and pressure to minimize off-site movement of pesticides. Avoid spraying during these conditions to avoid off-site movement of pesticides. Wind speed over 5 mph Temperature inversions Just prior to rain or irrigation (unless it is an appropriate amount, such as when incorporating a soil-applied pesticide) At tractor speeds over 2 mph Identify and take special care to protect sensitive areas (for example, waterways or riparian areas) surrounding your application site. Review and follow labeling for pesticide handling, personal protection equipment (PPE) requirements, storage, and disposal guidelines. Check and follow restricted entry intervals (REI) and preharvest intervals (PHI). ü After an application Record application date, product used, rate, and location of application. Follow up to confirm that treatment was effective. (/2) Pear Year-Round IPM Program Annual Checklist vii Download this form at

8 Pesticide application checklist ü Consider water management practices that reduce pesticide movement off-site. Consult relevant publications Reducing Runoff from Irrigated Lands: Orchard Floor Management Practices to Reduce Erosion and Protect Water Quality, UC ANR Publication 8202 (PDF), Reducing Runoff from Irrigated Lands: Causes and Management of Runoff from Surface Irrigation in Orchards, UC ANR Publication 824 (PDF), Protecting Surface Water from Sediment-Associated Pesticides in Furrow-Irrigated Crops, UC ANR Publication 8403 (PDF), Consult the Department of Pesticide Regulation Groundwater Protection Program (GWPA) Web site for pesticide information and mitigation measures. ( Install an irrigation recirculation or storage and reuse system. Redesign inlets into tailwater ditches to reduce erosion. Use drip rather than sprinkler or flood irrigation. Limit irrigation to amount required using soil moisture monitoring and evapotranspiration (ET). (For more information, see Reducing Runoff from Irrigated Lands: Understanding Your Orchard s Water Requirements, UC ANR Publication 822 (PDF), Consider using cover crops. Consider vegetative filter strips or ditches. (For more information, see Vegetative Filter Strips, UC ANR Publication 895 (PDF), Apply polyacrylamides in furrow and sprinkler irrigation systems to prevent off-site movement of sediments. Redesign inlets and outlets into tailwater ditches to reduce erosion. (For more information, see Reducing Runoff from Irrigated Lands: Tailwater Return Systems, ü Consider practices that reduce air quality problems. When possible, reduce volatile organic compound (VOC) emissions by decreasing the amount of pesticide applied, choosing low-emission management methods, and avoiding fumigants and emulsifiable concentrate (EC) formulations. Use the Department of Pesticide Regulation calculators to determine VOC emission rates from fumigant and nonfumigant pesticides. ( More information about topics mentioned on this checklist is available at the UC IPM Web site: For more about mitigating the effects of pesticides, see the Mitigation pages: (/2) Pear Year-Round IPM Program Annual Checklist viii Download this form at

9 General Information (Section reviewed /2) DORMANT TO DELAYED-DORMANT SAMPLING (/2) During the dormant to delayed-dormant period, take a beating tray sample for pear psylla. Also take a shoot sample to examine fruit spurs (short shoots containing the flower buds) and terminal buds for mites, psylla, scale, and scab lesions. If mealybugs are a chronic problem in the orchard, look under the tree bark at the base of the main scaffolds. Record your observations (example form available online). HOW TO SAMPLE For orchards less than 20 acres, a smaller sample size may be taken than indicated below, but adjust the treatment thresholds to your sample size. Beating Tray Samples In December, monitor overwintering psylla adults with 00 beating tray samples per 20-acre block. Each sample is three taps. Shoot and Spur Samples Once during the dormant season (December through early March), collect one shoot with a fruiting spur from the treetop and one from eye level from each of 50 trees in a 20-acre block, for a total of 00 spurs. (If you sample before February, pear psylla adults may be in the orchard but not their eggs. Also, pear rust mites become more evident in February when the buds begin to swell.) Use a 4 to 20X hand lens to examine the fruiting spur for: European red mite eggs Pear psylla eggs Pear rust mites Pearleaf blister mites Predatory mites Examine the shoot for: San Jose scales Pear scab twig lesions Count the number of spurs or shoots infested with these pests. Keep records of your results (example form available online). (/2) Dormant to Delayed-Dormant Sampling

10 DECISION TABLE Sample type Pest Management decision Beating tray Pear psylla If an average of two or more adults per 20 beats, treat once according to the Pear Pest Management Guidelines.... or... If more than 50 adults per 50 beats, treat twice according to the Pear Pest Management Guidelines. Resample following treatment to assess its effectiveness. Shoot and spur sample Pear psylla If two or more dormant spurs have psylla eggs, treat according to the Pear Pest Management Guidelines. European red mite If a dormant treatment was properly applied and: º more than 0% of the spurs are infested, monitor throughout growing season. º less than 0% of the spurs are infested, then probably will not be a problem in coming year. If no dormant treatment was applied and three or more spurs are infested in the sample of 00, monitor throughout growing season. Pear rust mite Pearleaf blister mite San Jose scale If two or more shoots are infested, treat according to the Pear Pest Management Guidelines. If any mites are present, treat according to the Pear Pest Management Guidelines. If a population of scale has developed in treetops, treat according to the Pear Pest Management Guidelines. Pear scab lesions Note areas of concern for future monitoring. Bark sample Mealybugs If mealybugs are a chronic problem, examine under the bark of trees and note presence for future monitoring. (/2) Dormant to Delayed-Dormant Sampling 2

11 PHEROMONE TRAPS (/2) In pears, pheromone traps are used to monitor adult emergence and flights of codling moth and obliquebanded leafroller. Consperse stink bug pheromone traps monitor both adult migration into the orchard and the population cycle within the orchard. Use the information obtained from the trap catches in conjunction with degree-day calculations (codling moth and obliquebanded leafroller) to schedule control actions. The traps are used to establish a biofix, which is an identifiable point in the life cycle of the pest at which you can begin degree-day accumulation. For example, the biofix for codling moth is the first date that moths are consistently found in traps for three consecutive days and sunset temperatures have reached 62ºF. GENERAL GUIDELINES FOR USING PHEROMONE TRAPS Use a minimum of one trap per 5 acres for both regular ( mg) and supercharged (0 mg) traps. Check traps twice a week until the biofix is established; thereafter, check traps weekly. Remove trapped insects from the trap after you count and record results (example form available online). For moth traps, replace trap bottoms monthly or when they become covered with debris. Follow manufacturer's recommendations for replacing pheromone lures. Store pheromone lures in a refrigerator or freezer. WHEN TO PUT OUT PHEROMONE TRAPS (consult individual pest section for best placement of trap) Pest When Placement Importance Codling moth Obliquebanded leafroller Consperse stink bug Regular mg pheromone plus DA lure traps Delta Region: early March North Coast areas: late March Sierra Foothill: late March to early April Supercharged 0 mg pheromone plus DA lure traps: at biofix 6 to 8 ft high To determine biofix early in the season and follow development To time when to deploy pheromone mating dispensers To determine after biofix whether mating disruption is working Top /3 of canopy To monitor population in pheromone-treated orchards Mid-April 6 to 8 ft high To monitor overwintering flight and to time treatments Early April To determine if adults are migrating into the orchard To follow seasonal development of population (/2) Dormant to Delayed-Dormant Sampling 3

12 SAMPLING AT BLOOM (/2) During the bloom season examine flower clusters for pear psylla, mites, caterpillars, and thrips to determine your management needs. Also look for mealybugs and boxelder bug eggs and adults if they are a problem in your orchard. Record your results (example form available online). HOW TO SAMPLE From 50 trees collect one flower cluster from the treetop and one at eye level for a total of 00 clusters. Examine flower clusters with a 0 to 4X hand lens for these pests: Pear psylla nymphs and eggs Mites º European red mite eggs and adults º Pear rust mite Caterpillars on leaves and blossoms º Obliquebanded leafroller º Miscellaneous caterpillars (e.g., green fruitworm, fruittree leafroller) Western flower thrips (tap clusters on hand and look for dislodged thrips) Mealybugs (grape, obscure) Western boxelder bug (eggs, nymphs, and adults) DECISION TABLE Pest Pear psylla European red mite Pear rust mite Obliquebanded leafroller Western flower thrips Mealybug nymphs (grape, obscure) Western boxelder bug Management decision If 2 or more flower clusters have eggs and or nymphs, treat according to the Pear Pest Management Guidelines. If between and 5 clusters have eggs, adding oil to the first codling moth spray may be adequate. If more than 5 clusters have eggs, treat with oil at egg hatch according to the Pear Pest Management Guidelines. If more than 0 clusters have eggs, add a miticide to the oil according to the Pear Pest Management Guidelines. If present, treat according to the Pear Pest Management Guidelines. If only one larva was found, use pheromone traps to monitor the first summer flight according to the Pear Pest Management Guidelines. If more than one larva is found, treat immediately according to the Pear Pest Management Guidelines. If several thrips can be seen on the cluster or dislodged onto a paper, treatment may be needed; see the Pear Pest Management Guidelines for details. If 4 or more top flower clusters are infested, treat according to the Pear Pest Management Guidelines. If less than 4 top flower clusters are infested, resample in a week. Spot treatments may be adequate in orchards near riparian areas; treat according to the Pear Pest Management Guidelines. (/2) Sampling at Bloom 4

13 SAMPLING DURING FRUIT DEVELOPMENT (/2) During the fruit development season examine fruit and leaves for the presence of, or damage caused by, pear psylla, mites, mealybugs, caterpillars, aphids, sawfly (pearslug), thrips, and plant bugs. Keep records of your observations (example form available online). HOW TO SAMPLE Take weekly samples of shoots that contain a fruit cluster, one from the treetop and one at eye level, from each of 20 trees in a 20-acre block. Examine both leaves and fruit for pests. Leaves Use a 0 to 4X hand lens to examine 5 leaves per shoot (total of 200 leaves) for: Pear psylla (nymphs, eggs, and honeydew) Mites: º European red mite (on both top and eye-level shoots) º Twospotted and other webspinning spider mites (early season, primarily on eye-level shoots; later in season top and eye-level shoots) Other pests: º Aphids (russeting and honeydew) º Pearslug (eggs and larvae) º Pearleaf blister mite (damage) º Katydids (feeding damage and nymphs on trees and cover crop) Fruit Examine fruit for evidence of pests or damage: Codling moth (stings and larval entries) Obliquebanded leafroller (look where fruit touch) Pear rust mite (russeting at calyx and stem ends) Boxelder bugs (mostly in areas near riparian corridors) Lygus bugs Stink bugs (also do a 30-minute search for adults) (/2) Sampling During Fruit Development 5

14 DECISION TABLE Sample type Pest Management decision Leaves Pear psylla If one or more shoots have psylla eggs or nymphs, treat according to the Pear Pest Management Guidelines. Fruit clusters European red mite Webspinning (e.g. twospotted) spider mites Aphids Pearslug Pearleaf blister mites Katydids Codling moth Obliquebanded leafroller If 0 or fewer European red mites or eggs are found per 00 inspected leaves, don't treat. If to 50 are found, treat with oil according to the Pear Pest Management Guidelines. If more than 50 are found, add a miticide with the oil according to the Pear Pest Management Guidelines. For Bartlett and Bosc varieties (thresholds for Asian pears and other varieties are generally higher): If to 50 mites per 00 leaves sampled, treat with oil according to the Pear Pest Management Guidelines. If more than 50 mites per 00 leaves sampled, add miticide to oil according to the Pear Pest Management Guidelines. In cool springs, evaluate damage according to the Pear Pest Management Guidelines. Spot treatments according to the Pear Pest Management Guidelines may be warranted for localized infestations. If present, plan to treat for this pest according to the Pear Pest Management Guidelines. Treatment may be necessary if foliage damage and nymphs are present on tree. If any eggs or larval entries are found, treat according to the Pear Pest Management Guidelines. If more than two clusters out of 40 contain leafrollers, treat according to the Pear Pest Management Guidelines. Pear rust mite If two or more pears have rust mites or if any pear has more than 30 mites, treat according to the Pear Pest Management Guidelines. Plant Bugs: Consperse stink bug Western boxelder bug Lygus bug If more than three fruit per 30 minute search show evidence of stink bug, treat according to the Pear Pest Management Guidelines. If bugs or damage are present, a spot treatment according to the Pear Pest Management Guidelines may be warranted. One damaged pear in 00 is cause for concern and calls for further sampling and evaluation of control need. (/2) Sampling During Fruit Development 6

15 HARVEST FRUIT SAMPLE (/2) At harvest, take a fruit sample from the bins to assess the effectiveness of the current year's IPM program and determine the needs of next year's program. Look for insects or damage, and try to determine what pest may have caused the damage. Record your observations (example form available online). HOW TO SAMPLE Examine 200 fruits per bin from 5 bins per orchard (or 20-acre block in larger orchards) for a total of,000 fruit for insect or disease damage. Look for the presence of Stings or deep entries: an indication of codling moth Superficial feeding on skin: an indication of obliquebanded leafroller larvae (summer generation) Black sooty mold: an indication of: º Pear psylla º Mealybugs Russeting: an indication of: º Pearleaf blister mite (Oval, convex spots less than 0.5 inch in diameter with a surrounding halo of clear tissue; spots frequently run together, leaving fruit deformed and misshapen.) º Pear rust mite (Uniform areas of russeting localized in stem end or calyx.) º Western flower thrips (Pockmarked areas of russeting and shallow scabbing.) Deep depressions: indication of: º Western boxelder bug (Depressions with white pithy areas under skin.) º Consperse stink bug (Depressions concentrated near stem end; white pithy areas in fruit under depression; may be confused with boxelder bug.) º Lygus bug (Similar to stink bug but feeding areas can have an open pustule; hard cells located in fruit under pustule). Misshapen fruit: an indication of early season caterpillar damage caused by obliquebanded leafrollers and miscellaneous caterpillars (green fruitworm, fruittree leafroller). Bumpy fruit: San Jose scale. (Red halos may be present around scale.) Other types of damage: º Katydids (Small [0.2 inch], deep bite marks.) º Mealybugs (May be present in calyx end.) Scabby areas on fruit surface: an indication of pear scab. (Fruit may also be misshapen.) (/2) Sampling During Fruit Development 7

16 POSTHARVEST SURVEY (/2) Monitor for pests during the postharvest season. Check fruit left on trees to assess the effectiveness of your codling moth program. Also, take a shoot sample to determine management needs for psylla, mites, and pear scab. Note whether pearslug is present in the orchard. Record your results (example form available online). HOW TO SAMPLE Fruit Sampling Collect 300 fruit left on trees after harvest. Examine for stings or deep entries to evaluate the effectiveness of the codling moth program. Shoot Sampling Collect one top shoot from 20 trees per 20-acre block. Using a 0 to 4X hand lens, look at 5 leaves on each shoot (for a total of 00 leaves) for the presence of European red mite: count the number of European red mites Pear psylla eggs and nymphs: count the number of infested shoots Pear scab Pearleaf blister mite: count the number of shoots with blistered leaves Twospotted and other webspinning spider mites: count the number of mites Pear rust mite: count the number of infested shoots Pearslug: note location of infestation Predatory mites DECISION TABLE Sample type Pest Management decision Fruit sample Codling moth If to 2% of the fruit (3 to 6 fruit) are infested, reevaluate your IPM program for the following year and be prepared to treat at first egg hatch of the overwintering generation, according to the Pear Pest Management Guidelines. Shoot sample Pear psylla (nymphs and eggs) European red mite Pear scab If 5 or more top shoots are infested, treat according to the Pear Pest Management Guidelines. If 50 to 200 mites per 00 leaves, treat according to the Pear Pest Management Guidelines. Use lower thresholds if predators are absent. If lesions are found, be prepared to treat in early spring. Webspinning spider mites Pear rust mite Pearleaf blister mite Pearslug For Bartlett and Bosc varieties (Asian and other varieties usually have higher thresholds): In early districts only, treat postharvest with oil if more than 50 mites per 00 leaves are present. If both pest and predaceous mites are present in ratio of 0:, treatment may not be needed. If 2 or more shoots are infested, treat according to the Pear Pest Management Guidelines. When 3 or more shoots show damage, plan to treat in the fall according to the Pear Pest Management Guidelines. Note localized infestations for future monitoring. (/2) Postharvest Survey 8

17 RELATIVE TOXICITIES OF INSECTICIDES and MITICIDES USED IN PEARS TO NATURAL ENEMIES and HONEY BEES (/2) Common name (example trade name and formulation) Mode of action Selectivity 2 (affected groups) abamectin (Agri-Mek EC) 6 moderate (mites, leafminers, psylla) Predatory mites 3 General predators 4 Parasites 4 Honey bees 5 Duration of impact to natural enemies 6 H L M/H I long to predatory mites and affected insects acequinocyl (Kanemite) 20B narrow (mites) III acetamiprid (Assail) 4A moderate (caterpillars, sucking insects) 7 8 M/H II moderate azadirachtin (Neemix) un broad (insects, mites) M L/M L/M II short Bacillus thuringiensis ssp. kurstaki A narrow (caterpillars) L L L III none bifenazate (Acramite) un narrow (mites) L L L II short bifenthrin (Brigade) 3A broad (insects, mites) H H H I long buprofezin (Centaur) 6 narrow (sucking insects) L H 9 L II long chlorantraniliprole (Altacor) 28 narrow (caterpillars) III chlorpyrifos (Lorsban EC) B broad (insects, mites) M H H I moderate clofentezine (Apollo) 0A narrow (mites) L L L III short clothianidin (Clutch) 4A M/H M/H I long Cydia pomenella granulovirus (Cyd-X) un narrow (codling moth) none none none III none diazinon (WP) B broad (insects, mites) L H H I moderate to long diflubenzuron (Dimilin) 5 narrow (codling moth, katydids) L H L II short dimethoate B broad (insects, mites) H H H I long esfenvalerate (Asana) 3A broad (insect, mites) H M H I moderate etoxazole (Zeal) 0B narrow (mites) 8 II short fenpropathrin (Danitol) 3A broad (insects, mites) H H H I fenpyroximate (Fujimite) 2A narrow (mites and some insects) H L L III short formetanate hydrochloride (Carzol) A broad (insects, mites) M/H H H II long, unless washed off hexythiazox (Savey, Onager) 0A narrow (mites) L L L II short to moderate imidacloprid (Provado) 4A narrow (sucking insects) 7 H I short to moderate kaolin clay (Surround) un broad (insects, mites) M M III long lambda-cyhalothrin (Warrior) 3A broad (plant bugs, beetles, caterpillars) H H H I moderate lime sulfur un narrow (mites, thrips) L/H L H II short methoxyfenozide (Intrepid) 8 narrow (caterpillars) L L L II none micronized sulfur un narrow (mites, thrips) L/H L/M H III short neem oil (Trilogy) un broad (soft-bodied) insects) L L L II short petroleum oil un broad (exposed insects, mites) L 0 L L II short to none phosmet (Imidan) B broad (insects, mites) H H H I moderate to long pyridaben (Nexter) 2A broad (insects, mites) M/H M I short pyriproxyfen (Esteem, Seize) 7C narrow (scale, beetles) L H 9 L II long spinetoram (Delegate) 5 broad (caterpillars, thrips, aphids, scales) L/M M M/H II moderate (continued next page) (/2) Relative Toxicities of Insecticides and Miticides Used in Pears to Natural Enemies and Honey Bees 9

18 Common name (example trade name and formulation) Mode of action Selectivity 2 (affected groups) spinosad (Entrust, Success) 5 narrow (caterpillars, thrips, aphids, scales) Predatory mites 3 General predators 4 Parasites 4 Honey bees 5 L M L/M II short spinosad (GF-20) 5 narrow (flies) L II short spirodiclofen (Envidor) 23 narrow (mites) L II spirotetramat (Movento) 23 narrow (aphids, scale) L L L II short thiacloprid (Calypso) 4A moderate (sucking insects, larvae) 7 M/H M/H II moderate thiamethoxam (Actara) 4A narrow (sucking insects) 7 M/H M/H I moderate H = high M = moderate L = low = no information un = unknown or uncertain mode of action Duration of impact to natural enemies 6 Rotate chemicals with a different mode-of-action group number, and do not use products with the same mode-of-action group number more than twice per season to help prevent the development of resistance. For example, the organophosphates have a Group number of B; chemicals with a B Group number should be alternated with chemicals that have a Group number other than B. Mode-of-action group numbers are assigned by IRAC (Insecticide Resistance Action Committee). For additional information, see their Web site at 2 Selectivity: Broad means it affects most groups of insects and mites; narrow means it affects only a few specific groups. 3 Generally, toxicites are to western predatory mite, Galendromus occidentalis. Where differences have been measured in toxicity of the pesticide-resistant strain versus the native strain, these are listed as pesticide-resistant strain/native strain. 4 Toxicities are averages of reported effects and should be used only as a general guide. Actual toxicity of a specific chemical depends on the species of predator or parasite, environmental conditions, and application rate. 5 Ratings are as follows: I Do not apply or allow to drift to plants that are flowering; II Do not apply or allow to drift to plants that are flowering, except when the application is made between sunset and midnight if allowed by the pesticide label and regulations; III No bee precaution, except when required by the pesticide label or regulations. For more information about pesticide synergistic effects, see Bee Precaution Pesticide Ratings (available online at 6 Duration: Short means hours to days; moderate means days to 2 weeks; and long means many weeks or months. 7 May cause flare-ups of spider mite populations. 8 Acute toxicity low, but reproductive capacity impacted. 9 Kills lady beetles. 0 Rating depends on rate used. Residual is moderate if solution is between ph of 7 to 8. Acknowledgements: This table was compiled based on research data and experience of University of California scientists who work on a variety of crops and contribute to the Pest Management Guideline database, and from Flint, M. L. and S. H. Dreistadt Natural Enemies Handbook: An Illustrated Guide to Biological Pest Control, ANR Publication (/2) Relative Toxicities of Insecticides and Miticides Used in Pears to Natural Enemies and Honey Bees 0

19 GENERAL PROPERTIES OF FUNGICIDES USED IN PEARS (/2) Common name (example trade name) Chemical class Activity Aureobasidium pullulans (Blossom Protect) Bacillus subtillis (Serenade Max) Mode of action (FRAC number) biological contact various ( ) low microbial contact various ( ) low bordeaux inorganic contact multi-site (M) low copper inorganic contact multi-site (M) low cyprodinil (Vangard) anilinopyrimidine mostly contact; slightly systemic difenoconazole/cyprodinil (Inspire Super) DMI 2 /anilinopyrimidine contact, systemic single-site (9) two, single-site modes of action (3/9) Resistance potential high medium Comments dodine (Syllit) guanidine systemic (local) unknown (U2) medium slow resistance by limiting applications to one per season or tank mixing with another fungicide fenarimol (Rubigan, Vintage) DMI 2 -pyrimidine systemic 6 (local) single-site (3) high fosetyl-al (Aliette) phosphonate systemic unknown (33) low kresoxim-methyl (Sovran) QoI 3 contact, systemic 6 single-site () high lime sulfur inorganic contact multi-site (M2) low incompatible with most other pesticides mancozeb (Dithane, Penncozeb, Manzate) oxytetracycline (Mycoshield, Fireline) Pseudomonas fluorescens (Blight Ban) carbamate (EBDC) 4 contact multi-site (M3) low antibiotic contact protein synthesis (4) high biological contact various ( ) low pyrimethanil (Scala) anilinopyrimidine mostly contact: slightly systemic pyraclostrobin/boscalid (Pristine) streptomycin (Ag- Streptomycin, Agri-Mycin, Firewall) single-site (9) Qol 3 /SDHI 7 contact, systemic two, single-site modes of action (7/) high high antibiotic systemic protein synthesis (25) very high sulfur inorganic contact multi-site (M2) low toxic to predatory mites and parasites tebuconazole (Tebuzol) DMI 2 systemic (local) single-site (3) high tebuconazole/ trifloxystrobin (Adament) thiophanate-methyl (Topsin- M, T-Methyl, Incognito) DMI 2 /Qol 3 systemic two, single-site modes of action (3/) medium MBC 8 systemic (local) single-site () very high toxic to earthworms with repeated usage trifloxystrobin (Flint) QoI 3 contact, systemic 6 single-site () high triflumizole (Procure) DMI 2 -imidazole systemic 6 (local) single-site (3) high ziram carbamate (DMDC) 5 contact multi-site (M3) low (/2) General Properties of Fungicides Used in Pears

20 Common name (example trade name) Chemical class Activity Mode of action (FRAC number) Resistance potential Comments Group numbers are assigned by the Fungicide Resistance Action Committee (FRAC) according to different modes of actions (For more information, see Fungicides with a different group number are suitable to alternate in a resistance management program. In California, make no more than one application of fungicides with mode-of-action group numbers, 4, 9,, or 7 before rotating to a fungicide with a different mode-of-action group number; for fungicides with other Group numbers, make no more than two consecutive applications before rotating to fungicide with a different mode-of-action group number. 2 DMI = demethylation (sterol) inhibitor 3 QoI = quinone outside inhibitor (strobilurin) 4 EBDC = ethylene bisdithiocarbamate 5 DMDC = dimethyl dithiocarbamate 6 Generally considered to have systemic action based on performance data but not yet proven experimentally. 7 SDHI = succinate dehydrogenase inhibitor 8 MBC = methyl benzimidazole carbamate = No information Acknowledgment: Adaskaveg et al., 207. Efficacy and Timing of Fungicides, Bactericides, and Biologicals for Deciduous Tree Fruit, Nut, Strawberry, and Vine Crops. (/2) General Properties of Fungicides Used in Pears 2

21 FUNGICIDE AND BACTERICIDE EFFICACY (6/7) FUNGICIDE EFFICACY Conventional Chemistry Fungicide*** Resistance Scab risk (FRAC#) Protectant Eradicant Flint 2 high () Fontelis high (7) Luna Sensation medium (7/) Inspire Super medium (3/9) Merivon medium (7/) Pristine medium (7/) ++++ Procure 4 high (3) Rally 5 high (3) Rubigan**,Vintage** high (3) Rhyme,Topguard 5 high (3) Captan 6 low (M4) +++ Dithane,Manzate, low (M3) +++ Penncozeb 6 Scala high (9) Sovran high () Syllit medium (U2) Tebucon,Toledo high (3) Topsin-M,T-Methyl, high () Incognito,Cercobin 3 Vangard high (9) Copper 6 low (M) ++ 7 Lime sulfur 6,8 low (M2) Ph-D,Oso high (9) ++ Sulfur 7 low (M2) ++ Ziram 6 low (M3) ++ FUNGICIDE EFFICACY Soft Chemistry (Biologicals and Natural Products) Fungicide Resistance Scab risk (FRAC#) Protectant Lime sulfur low (M2) ++ Sulfur 7 low (M2) ++ Actinovate low (Bio-) 3 +/++ Blight Ban low (Bio-) 3 +/++ Blossom Protect low (Bio-2) 3 +/++ Double Nickel 55 low (Bio-) 3 +/++ Regalia low (Bio-3) 3 +/++ Serifel 5 low (Bio-) 3 +/++ Serenade low (Bio-) 3 +/++ Copper 7 low (M) +/++ Eradicant Fungicide and Bactericide Efficacy (6/7) 3 Illustrated version at

22 BACTERICIDE EFFICACY Conventional Chemistry Fire blight Phytotoxicity Bactericide Resistance Growth risk Contact Systemic 5 Regulator/SAR Ag Streptomycin,Agri- very high (25) /- Mycin, Firewall Kasumin* high (24) /- MycoShield,FireLine high (4) /- Captan 6 low (M4) ++ Copper 7 low (M) ++ + Dithane,Manzate, low (M3) ++ Penncozeb 6 Actigard 2 low (P) Apogee 5 low ++ BACTERICIDE EFFICACY Soft Chemistry (Biologicals and Natural Products) Bactericide Resistance Fire blight Phytotoxicity 5 Growth risk Contac Systemic Regulator/SAR t Blossom Protect low (Bio-2) /- Copper 7 low (M) ++ + Actinovate low (Bio-) 3 +/++ +/- Blight Ban low (Bio-) 3 +/++ +/- Double Nickel 55 low (Bio-) 3 +/++ +/- Regalia low (Bio-3) 3 +/++ +/- Sanitizers 4 low +/++ Serenade low (Bio-) 3 +/++ +/- Lime sulfur low (M2) +++ Rating: ++++ = excellent and consistent, +++ = good and reliable, ++ = moderate and variable, + = limited and/or erratic, +/- = minimal and often ineffective, / = variable, = ineffective, ND = no data. * Registration pending in California. **Not registered, label withdrawn or inactive in California. *** Postharvest fruit registrations in California include: TBZ, Alumni, Penbotec, Scholar, and BioSpectra. Group numbers are assigned by the Fungicide Resistance Action Committee (FRAC) according to different modes of actions (for more information, see Fungicides with a different group number are suitable to alternate in a resistance management program. In California, make no more than one application of fungicides with mode-of-action group numbers, 4, 9,, or 7 before rotating to a fungicide with a different mode-of-action group number; for fungicides with other group numbers, make no more than two consecutive applications before rotating to fungicide with a different mode-ofaction group number. 2 High resistance potential to trifloxystrobin for apple and pear scab pathogen populations. 3 To reduce the risk of resistance development, start treatments with a fungicide with a multi-site mode of action; rotate or mix fungicides with different mode-of-action FRAC numbers for subsequent applications, use labeled rates (preferably the upper range), and limit the total number of applications/season. Cercobin is registered only on apples. 4 On pear, use only before white bud and after full bloom. 5 Labeled on apple only in California. 6 These materials show some efficacy and should be used in mixtures with antibiotics as a component of resistance management programs. Captan is registered on apples, whereas Dithane is registered on apples and pears. 7 Though copper may be effective for scab and blight control under low disease pressure, copper products may cause fruit scarring or russeting. 8 "Burns out" scab twig lesions when applied at delayed dormant and disrupts pseudothecial (or ascostroma) development when applied to leaves in fall. CAUTION: LIME SULFUR IS INCOMPATIBLE WITH MOST OTHER PESTICIDES WHEN USED AFTER BUDBREAK. CHECK BEFORE USE. Fungicide and Bactericide Efficacy (6/7) 4 Illustrated version at

23 9 In-season application eradicates powdery mildew. 0 Labeled on pear but not on apple. Growth regulators such as prohexadione calcium (Apogee) can be used in an integrated approach to reduce host susceptibility but do not have antibiotic activity against fire blight. Thus, Apogee was not included in the fire blight activity ratings. 2 Acibenzolar-S-methyl (FRAC P) is a host plant defense inducer known to stimulate the salicylic acid pathway. 3 Biologicals (Bio) can be divided into Bio-, -2, and -3 subgroups based on their active ingredients of bacteria, fungi, and plant extracts, respectively. 4 Sanitizers such peroxyacetic acid (e.g., Oxidate, Zerotol, Perasan A) are oxidizers that act immediately on contact. They are neutralized rapidly by reducing agents and are non-persistent. Note: Zerotol is registered only on apple, but not on pears. Perasan A is for postharvest use in sanitizing fruit only. 5 Higher numbers of +s indicate higher phytotoxicity. Acknowledgment: Adaskaveg et al., 207. Efficacy and Timing of Fungicides, Bactericides, and Biologicals for Deciduous Tree Fruit, Nut, Strawberry, and Vine Crops(932 KB, PDF). Fungicide and Bactericide Efficacy (6/7) 5 Illustrated version at

24 MOST EFFECTIVE TREATMENT TIMINGS FOR KEY DISEASES (6/7) Note: Not all indicated timings may be necessary for disease control. Disease Fall Delayed-dormant White bud Full bloom Fire blight Powdery mildew Scab Rating: +++ = most effective, ++ = moderately effective, + = least effective, = ineffective Petal fall/cover sprays Timings used will depend on orchard history of disease, length of bloom, and weather conditions each year. Protection of early tissue is important. Additional applications should be made according to infection periods as determined by the Mills table. 2 Disruption of pseudothecial (or ascostroma) development (fall) and inactivation of overwintering twig lesions (delayed dormant) occurs; effects of these treatments on disease control is uncertain. 3 Early applications are most effective; additional applications are made if mildew continues. 4 Start management program at the beginning of bloom and continue through bloom including "rat-tail" bloom throughout spring. Several models are available for forecasting infection periods and treatment timing. Models include: Maryblyt, Cougar Blight, etc. Acknowledgment: Adaskaveg et al., 207. Efficacy and Timing of Fungicides, Bactericides, and Biologicals for Deciduous Tree Fruit, Nut, Strawberry, and Vine Crops. (6/7) Most Effective Treatment Timings for Key Diseases 6

25 FUNGICIDE RESISTANCE MANAGEMENT (6/7) Note: Not all indicated timings may be necessary for disease control; whereas additional applications may be necessary under favorable conditions for disease (see Treatment Timing Table). Suggested fungicide bactericide, biological, and natural product groups are listed for each timing based on host phenology, weather monitoring, inoculum models, or environmental-disease forecasting models. How to use this table: ) Identify the disease(s) that need(s) to be managed. Know the disease history of the orchard, especially from the previous season. 2) Select one of the suggested fungicide groups. Numbers separated by slashes are pre-mixtures, whereas numbers grouped by pluses are tank mixtures. If several diseases need to be managed, select a group that is effective against all diseases. Refer to the fungicide efficacy table for fungicides belonging to each FRAC group. Group numbers are listed in numerical order within the suggested disease management program. 3) Rotate groups for each application within a season and, if possible, use each group only once per season, except for multi-site mode-of-action materials (e.g., M2) or natural products/biological controls (NP/BC). Disease Fall Delayed dormant Green tip Fire blight M M M, (24), 25, 4, P 4 Scab ---- M2 M, M2, M3,, 3, 7, 9, 3/9, 7/, 9, U2, U2+M-3, Bio- 5, Bio-2 5, Bio-3 5 Powdery mildew M2,, 3, 7, 9, 3/9, 7/, 9 Bloom Pink bud M, M2 2, 24 3, 25, 4, P 4, Bio- 5, Bio-2 5, Bio-3 5 M, M2, M3,, 3, 7, 9, 3/9, 7/, 9, U2, U2+M-3, Bio- 5, Bio-2 5, Bio-3 5 M2,, 3, 7, 9, 3/9, 7/, 9 Petal Fall (PF) M, 24 3, 25, 4, P 4, Bio- Bio- 5, Bio-2 5, Bio-3 5 M, M2, M3,, 3, 7, 9, 3/9, 7/, 9, U2, Bio- 5, Bio-2 5, Bio-3 5 M2,, 3, 7, 9, 3/9, 7/, 9 Spring Cover sprays M, 24 3, 25, 4, Bio- 5, Bio-2 5, Bio-3 5, PGR 6 M, M2, M3,, 3, 7, 9, 3/9, 7/, 9, Bio- 5, Bio-2 5, Bio-3 5 M2,, 3, 7, 9, 3/9, 7/, 9 Fixed copper (Ma) bactericides ( e.g., Kocide, Badge, Nordox, and ChampION ++ ) may cause phytotoxicity (russetting) when applied after full bloom. Other copper products (Mb) with lower metallic copper equivalent (i.e., MCE) such as copper complexes (e.g., Cueva, Copper Count-N, etc.) and copper sulfate pentahydrate (e.g., CS-2005, Phyton 27AG, etc.) have been reported to be less phytotoxic with applications following bloom because of lower MCE (see specific registrant label concerning product rates and number of times each material can be applied during the growing season). 2 M2 fungicides (e.g., liquid lime sulfur) that are registered for scab control have been used to thin-flowers in Washington state (Section 24c label) with one to two applications between 20-and 80% full bloom and subsequently have reduced the total number of flowers and potential infections sites for fire blight (indirect effects on disease). No label is available in CA for this usage. 3 The antibiotic kasugamycin is pending registration in CA but is registered federally. 4 Acibenzolar-S-methyl (FRAC P) is a host plant defense inducer known to stimulate the salicylic acid pathway. 5 Biologicals (Bio) can be divided into Bio-, -2, and -3 subgroups based on their active ingredients of bacteria, fungi, and plant extracts, respectively. In general, sulfur compounds are fungicidal and may affect applications of fungal biocontrols (e.g., Blossom Protect); whereas copper may affect applications of bacterial biocontrols (e.g., Actinovate, Blight Ban, Double Nickel 55, and Serenade). Rotations must consider these factors. 6 Plant growth regulators (PGR) such as prohexadione calcium (e.g., Apogee) reduce shoot growth and thus, indirectly reduce the number of infections sites for fire blight (indirect effects on disease). Acknowledgment: Adaskaveg et al., 207. Efficacy and Timing of Fungicides, Bactericides, and Biologicals for Deciduous Tree Fruit, Nut, Strawberry, and Vine Crops(932 KB, PDF) Fungicide Resistance Management (6/7) 7 Illustrated version at