Cordon (vine)

In viticulture, the canopy of a grapevine includes the parts of the vine visible aboveground - the trunk, cordon, stems, leaves, flowers, and fruit. The canopy plays a key role in light energy capture via photosynthesis, water use as regulated by transpiration, and microclimate of ripening grapes.Canopy management is an important aspect of viticulture due to its effect on grape yields, quality, , and the prevention of grape diseases. Various viticulture problems, such as uneven grape ripening, sunburn, and frost damage, can be addressed by skillful canopy management. In addition to pruning and leaf trim, the canopy is often trained on trellis systems to guide its growth and assist in access for ongoing management and harvest.

The vine is the main part of the grapevine, extending from the root system in the ground up to the cordons, or arms, of the vine. When the grape is young the trunk is very pliable and must be supported by stakes as part of a vine training system. The height of the trunk varies depending on grape variety and the type of trellis system being used and can range from 4 inches (10 cm) to 30 feet (10 m). During winter dormancy, the trunk can be vulnerable to extreme freezing conditions and will be sometimes buried and insulated with soil to protect it.

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