The expression "old friends pluck willows" conveys the idea of nostalgia and the fond memories associated with long-standing friendships. It suggests that friends, much like willow trees, have deep roots and a history that is worth cherishing.

This expression is rooted in the traditional Chinese custom of willow-branching, where willow branches are plucked and given to friends as a symbol of friendship and remembrance. The act of plucking willow branches is often associated with the Chinese festival of Qingming, which is a time for honoring ancestors and celebrating spring. The willow tree, with its long, flexible branches, has become a metaphor for the enduring nature of friendships.

Data from various studies on nostalgia and social relationships support the idea that this expression captures the essence of long-standing friendships. For instance, a study published in the Journal of Personality and Social Psychology found that nostalgia can enhance social bonds and provide a sense of belonging. The act of reminiscing about past experiences with friends can strengthen these bonds and create a shared sense of history.

Furthermore, the metaphor of the willow tree as a symbol of friendship is supported by its cultural significance in various societies. In many cultures, willow trees are associated with flexibility, adaptability, and resilience, qualities that are often associated with long-lasting relationships.

In conclusion, the expression "old friends pluck willows" conveys the enduring nature of friendships and the value of cherishing the past. It is a powerful metaphor that resonates with the universal human experience of forming and maintaining deep, meaningful connections with others.