Wherry's spleenwort facts for kids

Asplenium × wherryi, also called Wherry's spleenwort, is a rare hybrid fern. It grows in the Appalachian Mountains. This fern is a mix of two other ferns. Its parents are the mountain spleenwort (A. montanum) and Bradley's spleenwort (A. bradleyi). It is a sterile plant, meaning it cannot make seeds to reproduce. It is found in only a few places where its parent ferns grow together. Edgar T. Wherry first collected it in 1935. The fern was later named in his honor.

What Wherry's Spleenwort Looks Like

Asplenium × wherryi is a small fern that stays green all year. Its leaves, called fronds, look very similar whether they are fertile or not. The dark-colored part of the leaf stalk, called the stipe, can be up to 2 centimeters (about 0.8 inches) long. The main stem of the leaf, called the rachis, is green.

The leaf blades are shaped like a spear. They have ten to sixteen pairs of smaller leaf parts called pinnae. Near the base, the leaf blades are deeply cut into even smaller parts called pinnules. Higher up the leaf, the pinnae are lobed. Near the tip, the leaf is only cut into simple lobes. This fern does not produce working spores. It is thought to have three sets of chromosomes, which makes it sterile.

In general, A. × wherryi looks like a mix of its two parent ferns. The dark color on the leaf stalk of A. × wherryi goes all the way up. For A. bradleyi, the dark color goes further into the main stem. For A. montanum, only the very bottom of the leaf stalk is dark. The leaf blade of A. × wherryi is spear-shaped. A. bradleyi has a narrower spear shape. A. montanum has a more triangular leaf. How the leaf is cut is also in between its parents. The base looks like A. montanum, which is more deeply cut. The upper part looks like A. bradleyi, which has lobed pinnae.

How Wherry's Spleenwort Was Discovered

Edgar T. Wherry and Harry W. Trudell first found this fern in 1935. They were looking for A. bradleyi and A. montanum on a cliff in New Jersey. Wherry and Trudell found more A. bradleyi plants. They also found a group of the hybrid fern. Wherry wrote about his discovery. He did not formally describe the hybrid at that time. He did draw parts of it and said it was "exactly intermediate between parents."

The hybrid fern was not studied again until 1961. A group of plant scientists from the University of Illinois found some small ferns in Kentucky. They realized these were the same hybrid ferns Wherry had found. They used Wherry's original fern samples to formally describe the hybrid. They named it Asplenium × wherryi to honor him.

Later studies in 1963 also supported that it was a hybrid. These studies looked at the chemicals inside the ferns. A. × wherryi had chemicals found in both its parent ferns. It also had chemicals from another fern called ebony spleenwort (A. platyneuron).

Where Wherry's Spleenwort Grows

In theory, A. × wherryi could grow anywhere its parent ferns overlap. This area stretches along the Appalachian Mountains from New York to Georgia. It also includes parts of Indiana and Kentucky. However, this fern is very rare and found in only a few scattered spots.

It has been reported in New Jersey, Pennsylvania, Virginia, Kentucky, and Georgia. The Pennsylvania report was for just one plant. This plant grew for a few years in a place called Tucquan Glen. The original spot in New Jersey where it was found was reported destroyed in 1956. But A. bradleyi was found there again in 1960.

Habitat and Protection

Like its parent ferns, A. × wherryi grows in narrow cracks in acidic rocks. These rocks include quartzite or sandstone.