Research Report #59 — Azalea “May Apple”

Azalea © Hallie Schwab

For many years scientists and naturalists have been studying and observing the flora and fauna of the Shawangunk Ridge. Foremost among them was Daniel Smiley, for whom Mohonk Preserve’s Daniel Smiley Research Center is named. Dan wrote numerous reports summarizing his observations on various topics. This regularly occurring series will feature some of these reports; some hold tremendous scientific value today and just await an interested researcher to follow up, others showcase a quirky sense of humor or highlight an oddity of nature.

Read the Report: Azalea “May Apple”. October 1984. Daniel Smiley.

A Note from Paul C. Huth, Director of Research Emeritus: Working over the decades on Shawangunk natural and cultural history research at the Daniel Smiley Research Center, including for 15 years with Daniel Smiley at Mohonk, I am always interested in the merger of topics of natural history and the direct linkage to some aspect of the cultural history of the land. One example is the Azalea “May Apple.”

In 1984, on one of our twice monthly field trips to the Minnewaska State Park Preserve to collect water samples from Minnewaska Lake, Awosting Lake, and Fly Brook for pH testing, and to observe the distribution and occurrence of species and their phenology along the way, we would often encounter Ranger Joe Karsner out on the land. Joe, a long-time local resident, familiar with the ridge and its workings, would share what he had seen since our last visit, many times reporting something important in a remote back country area of the highlands of the ridge that we would not otherwise access. On one trip, Joe asked Dan about Azalea “May Apples,” and their onetime abundance on the ridge. Dan told Joe that he “knew them well at Mohonk in the 1930s, but have not seen one for some 40 years.” Apparently, it had been “a family custom to collect them for eating.” Joe told Dan “that in his youth May Apples were collected by the pail full, in the vicinity of Cragsmoor.” They ate some raw and pickled some to store for later use. He added that “He has not seen one in that area for at least 15 years.”

Dan’s “remembrance of May Apples at Mohonk was of a fleshy light green growth at the end of twigs of pink azaleas.” “The galls varied in size and shape from a ping pong ball to that of a small oblong potato...the texture was that of a fine grained melon.” Dan went on to say that they were a springtime occurrence, “found in May and early June.” “As a boy I considered them edible.”

The only reference we could find mentioning the May Apple, was finally located in the Research Center Library by our good friend Vincent J. Schaefer. It was found in “Our Northern Shrubs” (1903), by Harriet L. Keeler. “This peerless azalea (Rhododendron nudiflora) is familiarly known in New England as the honeysuckle, the swamp pink and the May apple. The latter name comes from the irregular excrescence, pale green and glaucous, growing on the leaves….Cool, crisp, and juicy, they are the delight of children, and put for a day in spiced vinegar, makes the first pickles of the year.” They were then thought to be insect galls.

1970 Herbarium Specimen of Pinxter-flower. © Collection of Mohonk Preserve Daniel Smiley Research Center. Photo by Paul C. Huth.

A question to friends at the Arnold Arboretum, revealed a reference to May Apples, in “Diseases and Pests of Ornamental Plants,” by Pascal P. Pirone, the New York Botanical Garden (1978), under the “Azalea Gall (Exobasidium vaccinii),” “When found in nature, these fleshy (fungal) galls are called ‘pinxter apples,’ and are eaten by those familiar with their qualities.” It is “largely composed of abnormal leaf tissue.”

Dan was clearly puzzled by the apparent loss of this plant curiosity from the past, and we were sure on our weekly spring field trips to make the effort to check many of the pinxter shrubs we knew along the way on both the Mohonk Preserve, and in the Minnewaska State Park Preserve. Working extensively on various aspects of plant distribution and vegetational history, we finally took the time to investigate the identification of the two very similar species of pinxter growing on the ridge, so that we could recognize the shrubs in the field. Going by several different common names, the Pinxter-flower, Rhododendron periclymenoides (=R. nudiflorum), and the Early or Mountain Azalea, Rhododendron prionophyllum (=R. roseum), were easiest to tell apart by fragrance when in bloom. The Early or Mountain Azalea could be identified by it’s exceptional sweet fragrance permeating the early May air for considerable distance around the flowering shrub. By contrast, the Pinxter-flower, while equally attractive, was odorless or nearly so. Also, of particular interest, was that the date of the beginning of bloom for both species was practically the same. We even occasionally found “both species growing side by side.”

Every spring over the decades, I continued to encourage the Mohonk Preserve Research staff to check for May Apples when out on the land in the spring, just as I had done with Dan. As I like to say, I still learn something new every day! Or, from naturalist John Burroughs, “to learn something new, take the path that you took yesterday.” On 24 May 2012, on a regular field trip to the Minnewaska State Park Preserve, literally taking the same route each time, the Research staff discovered two fleshy green growths on a Mountain Azalea shrub near Awosting Lake. I well remember how excited we all were when they got back to the Research Center and showed me what they had found. The notation in the record says it all-“Azalea Apples! First ones seen in 70 years!” They were found again on the same shrub on 5 June the next year.

Read the Report: Azalea “May Apple”. October 1984. Daniel Smiley.

With over 8,000 acres on the Shawangunk Ridge, Mohonk Preserve is the largest member and visitor-supported nature preserve in New York State.