O-zone Injury on Vegetables
Crystal Stewart-Courtens, Extension Vegetable Specialist
Eastern New York Commercial Horticulture

Common ozone symptoms are small, irregular, shaped spots that range in color from dark brown to black (stipple like) or light tan to white (fleck like). These spots are found only on the upper surface of the leaf. Very young and old leaves are less susceptible to ozone while newly mature leaves are the most susceptible. With severe damage, symptoms may extend to the lower leaf surface.
Insect feeding (red spider mite and some leafhoppers) produce flecks on the upper surface of leaves, much like ozone injury. Flecks from insect feeding are usually spread uniformly over the leaf surface while ozone flecks are concentrated in specific areas, usually most pronounced at the leaf tip and along the margins.
The most sensitive crops include: Bean, Broccoli, Muskmelon, Onion, Potato, Radish, Spinach, Sweet Corn, Tomato
Intermediate crops include: Carrot, Endive, Parsley, Parsnip, Turnip
Tolerant crops include: Beet, Cucumber, Lettuce

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Eastern New York Grapevine Pruning Workshops - Highland
March 19, 2026 : Eastern New York Grapevine Pruning Workshop
Higland, NY
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2026 Cornell Winter Fruit Webinar Series
January 22, 2026 : Blueberry Pruning and Soil Health to Minimize Pests and Maximize Yield
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January 29, 2026 : Cost of Production for Fruit Crops
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February 12, 2026 : Fire Blight Management Updates
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February 19, 2026 : Pink and Petal Fall Insecticides- Can We Strike the Right Balance?
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March 12, 2026 : Inoculating Orchards with Mycorrhizal Fungi
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Leading the Farm Team: Supervisory Skills for New Managers
April 14, 2026 : Session 1: Becoming a Supervisor
The transition from working alongside employees to supervising them can be challenging. This session explores the shift from individual contributor to supervisor and the mindset and skills needed to lead a team effectively. Participants will learn about the role of a supervisor, key leadership behaviors, and how to build trust and credibility with employees.
April 21, 2026 : Session 2: Improving Performance
This session will introduce the performance triad—clear expectations, training, and feedback—to support employee success. We will discuss practical communication strategies, how to give constructive feedback, and how supervisors can help employees improve their performance over time.
April 28, 2026 : Session 3: Managing Conflict
Supervisors are responsible for maintaining a professional and respectful workplace. This session covers some of the legal and ethical responsibilities of supervisors and the responsibilities managers have in addressing workplace concerns.
Participants will also explore common sources of workplace conflict, learn to recognize potential biases that can influence management decisions, and discuss practical approaches for addressing difficult situations and resolving conflicts at work.
