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Alfalfa PMG 12 19 11 UC IPM Pest Management Guidelines: ALFALFA September 2010 Contents (Dates in parenthesis indicate when each topic was updated) Alfalfa Year-Round IPM Program Checklist (11/06) ........................................................................................................................ iv General Information Integrated Pest Management (11/06) ................................................................................................................................................... 1 Selecting the Field (11/06) ................................................................................................................................................................... 2 Transgenic Herbicide-Tolerant Alfalfa (11/06) ................................................................................................................................... 3 Biological Control (11/06) ................................................................................................................................................................... 5 Sampling with a Sweep Net (11/06) .................................................................................................................................................... 6 Crop Rotation (11/06) .......................................................................................................................................................................... 8 Aphid Monitoring (9/07) ...................................................................................................................................................................... 9 Alfalfa Caterpillar and Armyworm Monitoring (11/06) .................................................................................................................... 10 Border-Strip Harvesting (11/06) ........................................................................................................................................................ 11 Harvest Scheduling (7/09) .................................................................................................................................................................. 12 Relative Toxicities of Insecticides and Miticides Used in Alfalfa to Natural Enemies and Honey Bees (9/10) ............................... 13 Insects and Mites (section reviewed 11/06) Alfalfa Caterpillar (9/10) .................................................................................................................................................................... 14 Beet Armyworm (9/10) ...................................................................................................................................................................... 16 Blister Beetles (11/06) ........................................................................................................................................................................ 18 Blue Alfalfa Aphid and Pea Aphid (4/08) .......................................................................................................................................... 19 Clover Root Curculio (11/06) ............................................................................................................................................................ 21 Cowpea Aphid (4/08) ......................................................................................................................................................................... 22 Grasshoppers (11/06) ......................................................................................................................................................................... 24 Ground Mealybug (11/06) .................................................................................................................................................................. 25 Leafhoppers (4/08) ............................................................................................................................................................................. 26 Mormon Cricket (11/06) .................................................................................................................................................................... 29 Sharpshooters (4/08) .......................................................................................................................................................................... 30 Silverleaf Whitefly (11/06) ................................................................................................................................................................ 32 Spider Mites (11/06) ........................................................................................................................................................................... 33 Spotted Alfalfa Aphid (4/08) .............................................................................................................................................................. 35 Threecornered Alfalfa Hopper (11/06) .............................................................................................................................................. 37 Thrips (11/06) ..................................................................................................................................................................................... 39 Variegated and Other Cutworms (11/06) ........................................................................................................................................... 40 Webworm (11/06) .............................................................................................................................................................................. 42 Weevils (Alfalfa and Egyptian Alfalfa) (9/10) ................................................................................................................................... 43 Western Yellowstriped Armyworm (9/10) ........................................................................................................................................ 46 Diseases (section reviewed 11/06) Alfalfa Dwarf (11/06) ......................................................................................................................................................................... 48 Alfalfa Mosaic Virus and Cucumber Mosaic Virus (11/06) .............................................................................................................. 48 Air Pollution (11/06) .......................................................................................................................................................................... 49 Anthracnose (11/06) ........................................................................................................................................................................... 49 Bacterial Wilt (11/06) ......................................................................................................................................................................... 50 Common Leafspot (11/06) ................................................................................................................................................................. 51 Continued on next page . An illustrated version of this guideline is available online at http://www.ipm.ucdavis.edu/PMG/selectnewpest.alfalfa-hay.html Publication 3430 University of California Agriculture and Natural Resources UC Statewide Integrated Pest Management Program UC IPM Pest Management Guidelines – ALFALFA Table of contents, continued Downy Mildew (11/06) ...................................................................................................................................................................... 51 Fusarium Wilt (11/06) ........................................................................................................................................................................ 52 Phymatotrichum Root Rot (11/06) ..................................................................................................................................................... 52 Phytophthora Root and Crown Rot (11/06) ....................................................................................................................................... 53 Rhizoctonia Root Canker (11/06) ...................................................................................................................................................... 54 Scald (Flooding and High Temperature Injury) (11/06) .................................................................................................................... 54 Sclerotinia Stem and Crown Rot (White Mold) (11/06) .................................................................................................................... 55 Seedling or Damping-off Diseases (11/06) ........................................................................................................................................ 56 Spring Black Stem (11/06) ................................................................................................................................................................. 57 Stagonospora Crown and Root Rot (11/06) ....................................................................................................................................... 57 Stemphyllium Leaf Spot (11/06) .......................................................................................................................................................
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