April 2021 Plant of the Month
Botrychium dissectum Spreng. forma obliquum (Muhl.) Clute; Cut-leaf Grape Fern
The April Plant of the Month is a native fern with statewide distribution. Grape fern is a wide spread species, with representation in appropriate forest habitats from Minnesota to Texas, east to the Atlantic seaboard. Mary Hough (1983) documents the plant in all 21 counties. Montgomery and Fairbrothers (1992) identifies the fern throughout the northern counties. Their studies found the plant is best represented in the southern counties on the Inner Coastal Plain. Witmer Stone (1910) describes the fern as common, and often associated with the cut leaf form.
New Jersey supports seven Botrychium species. Each is characterized by fleshy fronds of a variety of forms. Our Plant of the Month is found with two leaf forms, and was once considered separate species. Forms of the leaf include the entire margin, such as the one photographed in Mantua, Gloucester County, and a highly cut or dissected form, rightly name forma dissectum. Both leaf types occur in the same populations, and there are many intermediate examples of the two leaf shapes.
Our Plant of the Month fruits in July and August, with mature spores visible in September. There are no known uses of the plant. Its cousin, rattlesnake fern (Botrychium virginianum), had medicinal uses by Native Americans, and it is suspected a similar use could have been in practice for our cut-leaf grape fern.
JRA, 4/2021
