(Radio Iowa) – Many Iowa oak trees are producing a bumper crop of acorns this year. Aaron Steil, a horticulture specialist with Iowa State University Extension — says it’s a “mast year” for oaks.

The mast cycle is not unique to oak trees.

Steil says there is a theory of why trees do this and it’s related to the survival of the species.

In years when there’s an abundance of acorns, it’s also easier for humans to find viable seeds to replant.

In 1961, the legislature designated the oak as Iowa’s official state tree. There are a dozen species of oak trees found in Iowa.