Cornell Carbohydrate Model Results for April 26, 2017

Posted: April 26, 2017

Cloudy, warm weather may result in a greater tree response to chemical thinners this week.
Apple flowers, 2016. Photo: Rob Crassweller, Penn State

Apple flowers, 2016. Photo: Rob Crassweller, Penn State

We conducted this run at approximately 9:00 AM this morning. After much cloudy, cool weather in Central Pennsylvania, weather forecasters are calling for a period of warmer temperatures with cloudy conditions through Friday morning. The daily demand for carbohydrates is increasing across the state and especially for Berks County in the Southeast. Cloudy, warm weather results in higher respiration and greater carbohydrate demand leading to potentially greater tree response to chemical thinners. As mentioned previously, fruit size, chemical selection, drying conditions, spray volume, and other factors also contribute to tree response to thinners. We also are noticing some variability in the model and this is discussed in a follow-up article.

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Apple Carbohydrate Thinning Models for Pennsylvania Counties

For more information on the carbohydrate thinning model, visit Carbohydrate Thinning Model. For more details on factors that affect plant growth regulator performance and chemical thinner rates, visit Growth Regulators in Apple and Pear Production.

Contact Information

Robert Crassweller
  • Professor of Tree Fruit
Phone: 814-863-6163