Gum (botany)

Gum is a sap or other resinous material associated with certain species of the plant kingdom. This material is often polysaccharide-based and most frequently is associated with woody plants, particularly under the bark or as a seed coating. The polysaccharide material is typically of high molecular weight and most often highly hydrophilic or hydrocolloidal.

Many gums occur as seed coatings for plant species; the adaptive purpose of some of these gummy coatings is to create a time delayed germination of certain flora seeds. An example of such a gummy coating occurs in the case of Western poison oak, a widespread shrub in western North America.

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