Stretched catkins mid-March. Photo by Sally Weeks, Dendrology Specialist, Forestry and Natural Resources, Purdue University.
The domestic forsythia’s yellow blooms are a harbinger of spring for many, but have you ever wondered which of Indiana’s many native shrubs is the earliest to produce flowers? There are many that flower in April and May, but a few hardy species produce some rather uninteresting-looking flowers in mid-March, or earlier, depending on weather conditions.
Probably our earliest, and certainly our most common among these cool-weather flowering shrubs, is American hazel or hazelnut (Corylus americana). It is also known as filbert, which refers to the small tasty nut it produces. With the first warm weather in February, the male flowers that are in overwintering structures known as catkins begin to stretch and elongate. With enough days of temperatures in the 40s, the catkins will fully elongate (4” – 5”), and the tiny female flowers emerge from separate buds along the branches.
Male and female flowers mid-March. Photo by Sally Weeks, Dendrology Specialist, Forestry and Natural Resources, Purdue University.
In flower or even while the yellowish catkins are stretching, it stands out in the landscape as it does at no other time of the year. When searching for hazelnut, look for a large shrub, up to 10 to 12 feet, that grows in multi-stemmed dense clumps. It is commonly found in fencerows, woods edges, old pastures and other formerly disturbed areas where it prefers full sun.
Hazelnut is a member of the birch family – Betulaceae. Most members of this family have flowers (usually male) that overwinter in catkins.
Hazelnut leaves. Photo by Sally Weeks, Dendrology Specialist, Forestry and Natural Resources, Purdue University.
For more information, visit Indiana’s Native Plant Resources presented by Sally Weeks, Dendrology Specialist.
Sally Weeks, Dendrology Specialist
Forestry and Natural Resources, Purdue University