Eastern New York Commercial Horticulture Enrollment

Program Areas

  • Food Safety
  • Variety Evaluation
  • Market Development
  • Pest Management
  • Cultural Practices

Enrollment Benefits

  • Telephone / Email Consultations
  • Newsletter
  • Direct Mailings
  • Educational Meetings & Conferences
  • In-Field Educational Opportunities
  • On-Farm Research Trials

ENYCH Enrollment Form (PDF; 710KB)

Enrollee Login

Password:

Log In To Access:

  • Helpful Diagnostic Tool:
      What's wrong with my crop?

Not an Enrollee? Enroll Now!

Online Enrollment Form

How Copper Sprays Work and Avoiding Phytotoxicity

June 26, 2013

How Copper Sprays Work and Avoiding Phytotoxicity
Copper has been widely used in both conventional and organic production for some time. Copper was one of the first elements used as a plant fungicide (the other was Sulfur). Its discovery can be traced back to the famous origin of Bordeaux mixture, containing a mixture of copper sulfate (CuSO4) and slaked lime, and used for downy mildew control in French vineyards.

Recently, growers have asked me questions regarding the mode of action of copper and had  concerns about phytotoxicity. First, let's begin with how copper controls pathogens. Copper is usually applied in the fixed form which lowers its solubility in water. Fixed coppers include basic copper sulfate (e.g., Cuprofix Ultra Disperss), copper oxide (e.g., Nordox), copper hydroxide (e.g., Kocide, Champ), copper oxychloride sulfate (e.g., COCS), and copper ions linked to fatty acids or other organic molecules (e.g., TennCop, Cueva). The spray solution is actually a suspension of copper particles, and those particles persist on plant surfaces after the spray dries. Copper ions are gradually released from these copper deposits each time the plant surface becomes wet. The gradual release of copper ions from the copper deposits provides residual protection against plant pathogens. At the same time, the slow release of copper ions from these relatively insoluble copper deposits reduces risks of phytotoxicity to plant tissues. Copper ions denature proteins, thereby destroying enzymes that are critical for cell functioning. Copper can kill pathogen cells on plant surfaces, but once a pathogen enters host tissue, it will no longer be susceptible to copper treatments. Thus, copper sprays act as protectant fungicide/bactericide treatments, but lack post-infection activity.

Because different formulations have different properties when used as spray materials, growers need to learn how to read and interpret labels. The effectiveness of copper sprays is highly correlated with the amount of elemental copper that is applied. The metallic copper content varies widely by product. Potency also varies by how the product is prepared. Finely ground copper products are more active than coarsely ground ones. Professor Tom Zitter of Cornell University suggests that for vegetable crops. Begin by choosing a copper product with at least 20% or more copper as the active ingredient to insure the greatest release of copper ions.

There are several suggestions for avoiding phytoxicity (or plant injury) with copper sprays. Limit the copper ion concentration on plant surfaces by using copper products that are relatively insoluble in water, i.e. fixed copper. Copper can accumulate to high levels on plant tissue when sprayed repeatedly to cover new growth and there is no rain. In this situation, after a rain event, a large amount of copper ions may be released leading to phytotoxicity. Solubility of fixed coppers increases under acidic conditions. Copper sprays will become more phytotoxic if they are applied in an acidic solution. Most copper products are formulated to be almost insoluble in water at pH 7.0. As the pH of water decreases the solubility of the copper fungicides increases and more copper ions are released. If the water used is too acidic (below pH 6.0-7.0 depending on the copper formulation) excessive amounts of copper ions could be produced which may cause damage to fruit and foliage. Formulations vary in solubility hydroxides are more soluble than oxychlorides which are more soluble than tribasic copper sulphates and cuprous. Less soluble formulations are usually more persistent. Check the pH of your water source. Copper sprays generally cause more phytotoxicity when applied under slow drying conditions, such as when it's wet and cool.  Always read the label instructions follow the Copper and tank mix partner labels.
For a comprehensive list of Copper Products Used for Vegetable Disease Control see
http://vegetablemdonline.ppath.cornell.edu/NewsArticles/CopperFungicides2012.pdf


Sources: T. A. Zitter, Cornell University Department of Plant Pathology & Plant-Micrbiology and David A. Rosenberger, Professor of Plant Pathology, Cornell University's Hudson Valley Lab


more crops
Apples

Apples

Apricots

Apricots

Asparagus

Asparagus

Beets

Beets

Blueberries

Blueberries

Broccoli

Broccoli

Brussels Sprouts

Brussels Sprouts

Cabbage

Cabbage

Carrots

Carrots

Cauliflower

Cauliflower

Cherries

Cherries

Cucumbers

Cucumbers

Dry Beans

Dry Beans

Eggplant

Eggplant

Ethnic Vegetables

Ethnic Vegetables

Garlic

Garlic

Grapes

Grapes

Horseradish

Horseradish

Kohlrabi

Kohlrabi

Leeks

Leeks

Lettuce / Leafy Greens

Lettuce / Leafy Greens

Melons

Melons

Nectarines

Nectarines

Onions

Onions

Parsnips

Parsnips

Peaches

Peaches

Pears

Pears

Peas

Peas

Peppers

Peppers

Plums

Plums

Potatoes

Potatoes

Pumpkins / Gourds

Pumpkins / Gourds

Radishes

Radishes

Raspberries / Blackberries

Raspberries / Blackberries

Rhubarb

Rhubarb

Rutabaga

Rutabaga

Snap Beans

Snap Beans

Squash - Summer

Squash - Summer

Squash- Winter

Squash- Winter

Strawberries

Strawberries

Sweet Corn

Sweet Corn

Sweet Potatoes

Sweet Potatoes

Tomatoes

Tomatoes

Turnips

Turnips

more crops

Upcoming Events

Agricultural Supervisory Leadership Certificate Program - ASL 105: Employee Development and Training

June 25 - June 30, 2024 : ASL 105: Employee Development and Training

Online course is delivered through the user-friendly platform, Moodle. Materials will be available starting June 19, and live Zoom discussions will occur every Tuesday at 3 PM ET from June 25 to July 30, 2024. 

Topic areas include:

  • Setting clear expectations for farm teams
  • Designing engaging training programs
  • Providing effective performance feedback 
  • Streamlining onboarding processes for new hires
  • Cultivating a culture of continuous learning and growth
  • Personalized coaching and career planning strategies for farm personnel

View Agricultural Supervisory Leadership Certificate Program - ASL 105: Employee Development and Training Details

Virtual Orchard IPM Scout Training 2

June 25, 2024 : Virtual Orchard IPM Scout Training 2

Virtual Orchard IPM Scout Training 2

Tuesday June 25, 1:30-3:30PM   

Join us for the second live, virtual training on scouting of major insect pests of apple orchards. Anna Wallis (NYSIPM Program), Mike Basedow (CCE ENYCHP), and Janet van Zoeren (CCE LOFT), will broadcast from orchards in their region to discuss best practices for monitoring. We will review monitoring/scouting procedures for major economically significant pests. We will also share resources available for helping with identification of pests and forecasting pest activity.  

Who is this for? Farmers, farm employees, and industry members with IPM & pest management responsibilities, looking for new or refresher training.

View Virtual Orchard IPM Scout Training 2 Details

Airblast Sprayer Calibration Workshop

Event Offers DEC Credits

July 9, 2024 : Airblast Sprayer Calibration Workshop
Kinderhook, NY

University of New Hampshire Extension Field Specialist Emeritus, George Hamilton will demonstrate the importance of and best techniques to calibrate air blast sprayers. Proper calibration will ensure effective, efficient, economical and legal spraying.  Inadequate spray coverage is usually the cause of poor spray efficacy and additional spray applications. Overuse of some sprays results in unhealthy residues and can lead to fines.

Calibration should be done several times each season, or when you incorporate any new equipment or repairs - from the tractor to the nozzle.  Join us for a refresher or send new employees for training.  This workshop is open for any grower that relies on an airblast sprayer to deliver plant protectants to fruit or vegetable crops. 

View Airblast Sprayer Calibration Workshop Details

Announcements

Resources from CCE ENYCHP!


This website (https://enych.cce.cornell.edu/) contains our calendar of upcoming programs and registration links. For updated programmatic information, technical resources and links to newsletters please see our program blog site: https://blogs.cornell.edu/enychp/.
We also maintain the following online resources that you can view directly from these links:

• CCE ENYCH YouTube (program videos): https://www.youtube.com/channel/UCSk_E-ZKqSClcas49Cnvxkw

• CCE ENYCH Facebook (program social media): https://www.facebook.com/CCEENYCHP/

• CCE ENYCH Instagram (program social media): https://www.instagram.com/cceenychp/?hl=en


NEWSLETTERS  |   CURRENT PROJECTS  |   IMPACT IN NY  |   SPONSORSHIP  |   RESOURCES  |   SITE MAP