Gardening resources > Pests > What's killing my plants?
Cornell University Department of Horticulture
Gardening resources
Cornell gardening resources What's killing my plants?
The most asked-about plant pathogens in New York State.
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David Chinery, CCE Rensselaer County educator compiled this list for the Capital Region Master Gardener Volunteer training. We added the links to more information and pictures about these common plant diseases.

Woody Plants:

1. Apple scab (apple) 2. Apple-cedar rust (apple and juniper) 3. Anthracnose (dogwood, oak, maple, sycamore) 4. Bacterial crown gall (small euonymus) 5. Black knot of plum (plum, cherry) 6. Black spot of rose (rose) 7. Phytophthora wilt (rhododendron) 8. Powdery mildew (lilac) 9. Tar spot (maple)

Herbaceous plants:

1. Botrytis (peony) 2. Brown rot (fruits of grape, strawberry, etc.) 3. Blossom end rot (tomato) 4. Wilt (Clematis) 5. Early blight (tomato) 6. Leaf spots (many perennials, including Rudbeckia 'Goldsturm') 7. Necrotic spot virus (impatiens) 8. Powdery mildew (phlox, beebalm, cucurbits) 9. Rust (hollyhock) 10. Volutella blight (Pachysandra)


General: See Cornell Gardening Resources Common lawn diseases.

Brown patch Fairy rings Anthracnose on Turfgrass More turf disease factsheets.


Slime mold (mulch) Sphaerobolus spore packets (everywhere) 4. Damping off (seedlings)

Copyright, Department of Horticulture, Cornell University.

Website design: Craig Cramer

Mention of trade names and commercial products is for educational purposes; no discrimination is intended and no endorsement by Cornell Cooperative Extension or Cornell University is implied. Pesticide recommendations are for informational purposes only and manufacturers' recommendations change. Read the manufacturers' instructions carefully before use. Cornell Cooperative Extension and Cornell University assumes no responsibility for the use of any pesticide or chemicals. Some of the links provided are not maintained by Cornell Cooperative Extension and Cornell University. Cornell Cooperative Extension and Cornell University are not responsible for information on these websites. They are included for information purposes only and no endorsement by Cornell Cooperative Extension or Cornell University is implied. Cornell Cooperative Extension provides equal program and employment opportunities.