What is the origin of the idiom "plum tree" and when to use it?

The idiom "plum tree" has its origin in the concept of a literal plum tree. The plum tree is known for producing sweet, succulent fruits that are highly desirable. In the context of the idiom, the metaphorical plum tree symbolizes an opportunity or benefit that is coveted and valued. Just as people would compete for the choicest plums on a tree, individuals in professional or political settings strive to attain the most advantageous positions or opportunities.