horse put out to pasture in spring
Refers to a horse that is released to graze in spring, a seasonal image in traditional Japanese life.
The spring-grazing horse is eating grass in the field.
hobbyhorse
A toy horse, often a stick with a horse's head, used in children's play or traditional performances.
The child is playing, riding a hobbyhorse.
Compound of 春 (spring) and 駒 (horse). The exact historical derivation is uncertain; the word is conventionally associated with the two senses given.