Field Guide for Integrated Pest Management in Hops

Table of ContentsIntroductionPest Management, Crop Loss, and IPM..............................1Principles of Integrated Pest ManagementSystems-level Management.................................................1Pest and Natural Enemy Identification................................2Pest and Natural Enemy Biology and Life History..............2Economic Injury Levels andEconomic (Action) Thresholds..................................2Monitoring for Pests, Damage, and Treatment Success........3Multi-tactic Management Approaches................................3Pesticide Toxicology and SelectivityPesticide Toxicity Ratings....................................................4Pesticide Resistance Management........................................6Disease ManagementFungal and Bacterial DiseasesAlternaria Cone Disorder..........................................8Black Root Rot.........................................................9Downy Mildew.......................................................10Fusarium Canker....................................................15Fusarium Cone Tip Blight......................................16Gray Mold..............................................................17Powdery Mildew.....................................................18Red Crown Rot.......................................................22Sclerotinia Wilt (White Mold)................................23Sooty Mold.............................................................24Verticillium Wilt.....................................................25Diseases of Minor Importance.................................27Virus and Viroid DiseasesCarlavirus Complex: American hop latent virus,Hop latent virus, and Hop mosaic virus...............28Apple mosaic virus....................................................29Hop stunt viroid.......................................................30Other Viruses, Viroids, and Virus-like Agents.........32NematodesHop Cyst Nematode...............................................34Abiotic DiseasesHeptachlor Wilt......................................................35Arthropod and Slug Pest ManagementCalifornia Prionus Beetle.....................................................36Hop Aphid..........................................................................38Garden Symphylan..............................................................40Hop Looper and Bertha Armyworm ..................................42Root Weevils.......................................................................44Twospotted Spider Mite......................................................46Minor Arthropod and Slug Pests ........................................49Beneficial ArthropodsPredatory Mites................................................................52Predatory Lady BeetlesAphid Feeders.........................................................54Mite Feeders...........................................................57Predatory BugsMinute Pirate Bug...................................................58Big-Eyed Bug..........................................................59Predatory Mirid......................................................59Assassin Bugs..........................................................60Damsel Bugs...........................................................60Chart of Seasonal Development for Key Groups ofPredatory Athropods...............................................61Parasitic Wasps (Parasitoids)..............................................62Predatory Thrips...............................................................63Predatory and Parasitic Flies .............................................64Other Beneficial Arthropods and Pathogens......................66Weed Management...............................................69Planning a Weed Management Program...........................70Prevention........................................................................70Weed Seedling Identification............................................71Cultural Tactics.................................................................72Herbicides........................................................................72Table of Efficacy Ratings for Weed ManagementTools in Hops.........................................................75Calculating Treated Acres versus Sprayed Acres.................76Common Symptoms of HerbicideInjury on Hop........................................................77Nutrient Management and Imbalances.......79Index............................................................................81