Signs of spring are often associated with the return of warmer weather and the blooming of flowers. Tractors, robins, croci, BUDS, THAWS, tulips, and crocuses are all signs of spring. Tractors are large machines used for farming and other outdoor work, while robins are small birds that are often seen in the springtime. Croci are a type of flower that blooms in the spring, and BUDS are the beginnings of flowers that can be seen on trees and plants. THAWS refer to the melting of snow and ice, while tulips and crocuses are two types of flowers that bloom in the spring.