The oak tree represents the yearning of a stranger for his hometown and for his family. When his family is going to travel, people will also hang red ribbons on the trees to pray for his family's well-being. If one's family is away from home for a long time, people will take it as a way to express their missing for them.

Oak trees are tall and majestic, it not only represents a strong force, but also represents a firm belief, at the same time, oak itself is a sacred tree, it is also a symbol of glory.

Source: @ericamarietattoo