Resources on this page are not explicit and sound judgement should be used when considering any information used for design. In some cases, laymen's terms are used in-lieu of actual engineering terms. Consulting an expert is recommended.
Washington State Tree Fruit Association, Dec, 2016
Presentation from the WSTFA Horticulture Show
Questions and Answers:
Q: I will be installing netting soon, will a standard trellis support the net?
A: There is no "standard trellis" because installations and designs vary by orchard and enterprise. The answer to this question is that a trellis designed for netting will support the load. If a "standard trellis" was designed outside of netting loads, then careful considerations should be taken when installing cloth or superstructure of any type. This will add live and dead loads that need to be sized through the material correctly.
Q: How would you recommend attaching wires to posts?
A: Reference materials are available from wire companies that outline the correct way to secure a wire. With that being said, wire loads are point loads which can cause local damage to trellis posts. Distributing loads over a surface will help mitigate these risks.
Q: How important is my soil and should I sample?
A: Soil is the foundation for your trellis and adequately designing your system starts with understanding what material below ground you have to work with. Testing for soil strength will help determine how much the soil can hold. This will correlate to a correctly designed trellis.
Q: How deep should my posts be set:
A: All posts are different, for example a shovel with a 1" wood handle will not need to be set at the same depth as a 20ft, 8" metal tube to ensure a "fixed base". In "general" consider setting 3"-6" wood posts to 1/3 of the trellis height, in a "stable soil." Rock is different from sandy and water content is important.
Q: Can I install a trellis on a hill?
A: Yes. A correctly designed trellis system will consider topography as a factor.
Q: Is vertical trellis better than angled trellis?
A: Trellises should match your horticultural preference. The best trellis for you is the one that works towards stabilizing your system for all variables including plants and structure.
Q: Does the TrellX model consider wind loading?
A: Yes. All TrellX designs account for important factors including winds and gusts. We use weather data to assess a site which ultimately increases the confidence of the TrellX model.
Q: Does the Trellx model apply to my region?
A: Yes. We provide the basic information via the TrellX model to be used across the world. We also offer our services to fruit growing regions in Washington State, California, Oregon, Florida, New York, and Michigan. We can provide you with the right tools to make your trellis stable.