Plant Disease Diagnostics Clinic

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    • Deciduous Tree Leaf Disease Quick Reference Quiz
    • Diplodia Shoot Blight and Canker Quiz
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    • Foliar Nematodes Quiz
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    • Helminthosporium Turf Diseases Quiz
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    • Home Vegetable Garden Fungicides Quiz
    • Hosta Virus X Quiz
    • Hot-Water Seed Treatment for Disease Management Quiz
    • Huitlacoche Quiz
    • Impatiens Downy Mildew Quiz
    • Impatiens Necrotic Spot (INSV) Quiz
    • Iris Severe Mosaic Quiz
    • Late Blight Quiz
    • Lawn Disease Quick Reference Quiz
    • Leaf and Glume Blotch of Small Grains Quiz
    • Leaf Blotch Diseases of Wheat Quiz
    • Lichens Quiz
    • Microdochium Patch Quiz
    • Nectria Canker Quiz
    • Oak Wilt Quiz
    • Peach Leaf Curl Quiz
    • Phomopsis Tip Blight Quiz
    • Phytophthora Root and Stem Rot of Soybean Quiz
    • Phytophthora Root Rot of Christmas Trees Quiz
    • Pink Eye of Potato Quiz
    • Plant Problems to Watch for in 2023
    • Plant Problems to Watch for in 2024 Quiz
    • Plant Problems to Watch for in 2025 Quiz
    • Plant Problems to Watch for in 2026 Quiz
    • Plum Pox Quiz
    • Potato Scab Quiz
    • Powdery Mildew – Deciduous Woody Ornamentals Quiz
    • Powdery Mildew – Herbaceous Ornamentals Quiz
    • Powdery Mildew – Vegetable Quiz
    • Powdery Mildew of Wheat Quiz
    • Powdery Scab Quiz
    • Purple-Bordered Leaf Spot Quiz
    • Ralstonia Wilt Quiz
    • Raspberry Anthracnose Quiz
    • Red Star Rust Quiz
    • Red Thread Quiz
    • Rhizosphaera Needle Cast Quiz
    • Root and Crown Rots Quiz
    • Root Rots in the Garden Quiz
    • Root Rots on Houseplants Quiz
    • Root-Knot Nematode Quiz
    • Rose Rust Quiz
    • Sclerotinia Stem Rot of Soybean Quiz
    • Septoria Leaf Spot Quiz
    • Silver Leaf Quiz
    • Slime Molds Quiz
    • Southern Blight Quiz
    • Soybean Rust Quiz
    • Soybean Vein Necrosis Disease Quiz
    • Stinkhorns Quiz
    • Sudden Death Syndrome of Soybean Quiz
    • Sudden Oak Death Quiz
    • Swiss Needle Cast Quiz
    • Tar Spot of Trees and Shrubs Quiz
    • Tatters Quiz
    • Ten Common Plant Diseases/Disorders You Can Diagnose by Eye Quiz
    • Thousand Cankers Disease Quiz
    • Thyronectria Canker Quiz
    • Tobacco Mosaic Quiz
    • Tobacco Rattle Quiz
    • Tomato Spotted Wilt of Potato Quiz
    • Tubakia (Actinopelte) Leaf Spot Quiz
    • Typhula Blight Quiz
    • Vegetable Disease Quick Reference Quiz
    • Verticillium Wilt of Trees and Shrubs Quiz
    • Verticillium Wilt of Vegetables Quiz
    • Volutella Blight Quiz
    • Weir’s Cushion Rust of Spruces Quiz
    • White Mold Quiz
    • White Pine Blister Rust Quiz
    • Winter Burn Quiz
    • Wood Mulch and Tree Health Quiz
  • Where’d It Go?
  • Wisconsin Disease Almanac 2013
  • Wisconsin Disease Almanac 2014
  • Wisconsin Disease Almanac 2015
  • Wisconsin Disease Almanac 2016
  • Wisconsin Disease Almanac 2017
  • Wisconsin Disease Almanac 2018
  • Wisconsin Disease Almanac 2019
  • Wisconsin Disease Almanac 2020
  • Wisconsin Disease Almanac 2021
  • Wisconsin Disease Almanac 2022
  • Wisconsin Disease Almanac 2023
  • Wisconsin Disease Almanac 2024
  • Wisconsin Disease Almanac 2025
  • Wisconsin Disease Almanac 2026
  • Wisconsin Disease Almanac Index
  • Wisconsin Hort Update Archive

Green_Peach_Aphids_on_Chrysanthemum_Leaf

July 6, 2015 213 × 216 Green_Peach_Aphids_on_Chrysanthemum_Leaf
Green peach aphids on the underside of a chrysanthemum leaf. (Photo courtesy of L. Lindquist, OARDC.)

Green peach aphids on the underside of a chrysanthemum leaf. (Photo courtesy of L. Lindquist, OARDC.)

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University of Wisconsin-Madison

University of Wisconsin-Madison

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Watch Talks & Workshops:

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Read/Listen to Resources:

  • Limerickettsia Book Mushroom for Menu
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  • Plant Disease Pointers (Blog)
  • Scientific Publications
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Plant Disease Diagnostic Clinic

1630 Linden Dr. Room 183

Madison, Wisconsin 53706

608-262-2863

pddc@wisc.edu

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UW-Madison       College of Agricultural and Life Sciences
UW-Madison Department of Plant Pathology

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