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Ornamental Landscape Webinar Series: Disease Updates

  • Thursday, October 28, 2021, 6:00 PM - 7:30 PM

There will be two presentations. Each will be 30 minutes followed by 10 to 15 minutes of Q&A.

What Hasn’t Happened in 2021?

Margery Daughtrey, Plant Pathologist, Cornell University, LIHREC

Fungi, bacteria, phytoplasmas, oomycetes AND nematodes went after ornamentals in nurseries and landscapes this year. 2021 was marked by beech leaf disease, boxwood blight, Taphrina on willow oak and cherry, Dutch elm disease, Massaria disease and powdery mildew on London plane, powdery mildew on dogwood, Septoria on red osier dogwood, Diplodia on Blue Atlas cedar and pine, Cristulariella blight on maple, anthracnose on hydrangea, bacterial leaf spots on milkweed and peach, fire blight on apple, aster yellows on echinacea, Seiridium canker and Phyllosticta on arborvitae, black mildew on tulip poplar, tar spot on maple, Stigmina and Rhizosphaera on Colorado blue spruce. On the roots we had Thielaviopsis on Ilex and dianthus, and Cylndrocarpon on Buxus and arborvitae, plus Phytophthora on rose, coreopsis and rhododendron. What do these diseases look like, what do you need to know about their biology, and how can we keep them from returning? Margery will cover relevant details of these problems and give you cultural pointers and treatment suggestions so that there can be a shorter list of plant plagues next year!

Steps Towards an Oak Wilt Early Warning System

Karen Snover-Clift, Cornell University

Oak wilt, caused by the fungus, Bretziella fagacearum, was first discovered in upstate New York in 2008. In 2016, surveys found two additional locations, Long Island and in the Canandaigua area, each at least 180 miles apart from the original site and from each other. A tactic to reduce the number of trees lost to an oak wilt infection is the development of early detection methods that identify the pathogen in an area before trees display symptoms. This presentation will review two options that may be used as early warning tools for the detection of the oak wilt pathogen.

Limited in-person viewing of the live webinar will be available. Contact Mina Vescera at 631-603-9613 or mv365@cornell.edu to reserve your spot. Masks are required regardless of vaccine status. In-person viewing will be subject to last-minute cancellations due to Covid-19 CDC guidelines and CCE-Suffolk Covid-19 policy.






Mina Vescera
Nursery and Landscape Specialist


This event is online

Last updated October 13, 2021