Skip to main content Skip to navigation

Tree Fruit

Tree Fruit Research and Extension

WSU Tree Fruit Research and Extension develops and applies research-based information for sustainable tree fruit production in Washington and the world.

Recent News

WA 38/Cosmic Crisp® pre-harvest events scheduled and 2020 Documents available

Published on
It’s T minus 50-60 days before WA 38/Cosmic Crisp® harvest season begins. Color and size are coming on and there is great anticipation for a sizable…

Case studies on tree removal for X-disease phytoplasma and Little cherry virus

Published on
By Tianna DuPont, Chris Strohm, Cody Molnar, Ricardo Naranjo, WSU Extension; Garret Bishop, GS Long. August 8, 2020 August and early September are good times…

FSA Tree Assistance Program Offers Support for Little Cherry Tree Removal

Published on
New August 2020 when X-disease or Little Cherry infections reach or exceed 20% of a stand the whole block may be eligible for tree loss…

Updated list of Labs testing for Little Cherry Virus and X-disease Phytoplasma

Published on
For an updated list of labs which have passed proficiency testing see

Manejo de la carga frutal: De vuelta a lo básico

Published on
El manejo de la carga frutal es un tema de gran importancia para los productores de fruta. Con todos los factores que pueden afectar el…

Questions and Answers on Insect Vectors of X-disease Phytoplasma

Published on
Interview with Tobin Northfield, WSU Entomology.

Wildfire season has arrived

Published on
The National Interagency Fire Center in Boise, ID issued its Significant Wildland Fire Potential Outlook on August 1, 2020.  The agency predicts that the northwestern…

More News


Extension ITT Coordinator for TF Postharvest Systems

This is a fantastic opportunity to collaborate with the tree fruit industry to capture opportunities and solve challenges in postharvest systems. The application is online only here. If you have specific questions about the position…

ITT Publications Coordinator for Tree Fruit Extension

Here’s a great opportunity to work with the WSU Tree Fruit Extension Team to ensure outreach is effectively delivered across multiple platforms to communicate with a diverse audience including tree fruit growers, allied industry, orchard…

Upcoming Events


Taiwan/China Export Training – WebEx session 2

Event Details


Pear Rootstocks & Systems Virtual Field Tour

Online webinar
Event Details


Taiwan/China Export Training – WebEx session 3

Event Details


Webinar: The Role of Dendrometers for Irrigation Management in Apple

Event Details


Pesticide Pre-License Review Webinars (August 31)

Event Details

More Events

Featured Videos

Symptoms of Little Cherry Virus and X-disease Phytoplasma

X-disease phytoplasma and Little cherry virus 2 cause small, pale deformed fruit in cherries. This video shows symptoms in a number of varieties.

X-disease Vector Management

Tobin Northfield, WSU Entomology shows how to identify and trap for important leafhopper vectors of X-disease phytoplasma.

Using Irrigation Sensors – Troy Peters

WSU Biological Systems Engineering’s Troy Peters describes common types of irrigation sensors and how to use them. Part of ‘Virtual Fielday’ May 2020. Virtual Field Day hosted by Tianna DuPont, WSU Extension, Troy Peters, WSU…

Monitoreo y muestreo para la enfermedad de la cereza pequeña

Recomendaciones para el monitoreo y toma de muestras para identificar la presencia o ausencia de la enfermedad de la cereza pequeña en sus huertas.

Scouting and Sampling for Little Cherry Disease

Tips on scouting and sampling for X-disease and Little cherry disease which cause small, pale unmarketable fruit in cherries. By WSU Extension, OSU Extension and the Good Fruit Grower. Funding provided by a grant from…

Cost Share Availability – Irrigation Efficiencies Virtual Field Day

Sandy Letzing, Cascadia Conservation discusses cost share availability at ‘virtual field day’ May 2020. Virtual Field Day hosted by Tianna DuPont, WSU Extension, Troy Peters, WSU Biological Systems Engineering, Lee Kalcsits, WSU Horticulture. Project funders…

More Videos

Recent Publications

Apple Scion and Rootstock Contribute to Nutrient Uptake and Partitioning under Different Belowground Environments

Soil environment strongly contributes to tree growth and development, affecting nutrient and water uptake. Composite woody perennials, like apple, are a combination of two genetically different parts: a rootstock and a scion, and yet, the…

Optimization of Light Interception, Leaf Area and Yield in “WA38”: Comparisons among Training Systems, Rootstocks and Pruning Techniques

As apple orchards have transitioned to high-density plantings, proper training systems are required to manage increased leaf area. Leaf area index (LAI) is defined as the ratio between leaf area to ground area (m2/m2) and…
Image of fruit tree row in a compost treated orchard.

Compost Use For Tree Fruit

Compost can help improve soil quality and nutrient, water, and pest regulation. High-quality soil holds water and nutrients like a sponge, slowly releasing them over time to meet tree needs. High-quality soil can also suppress…

Soil Health in Orchards

Orchard soil health, or soil quality, is the capacity of soil to support productive trees over time without negatively affecting the surrounding environment. Soil health is influenced by interacting biological, physical, and chemical properties of…
lots of thick white fluff attached to the end of a small branch and hanging down

Perceptions and outcomes of conventional vs. organic apple orchard management

Highlights: Management goals were similar for organic and conventional apple orchards; Organic orchards employed more selective pesticide programs; Conventional and organic orchards did not differ in soil quality and insect counts; Integrated practices may be…

More Publications

Get Connected

Washington State University