Pennsylvania State Flower: Mountain Laurel

Mountain laurel (Kalmia latifolia) is a familiar shrub. While common, it is also extraordinary. A part of Pennsylvania’s folklore as the state flower and also studied by scientists for its biomechanics, this broadleaf evergreen abounds in mystique.

Since the early 18th century, mountain laurel has been cultivated as a flowering ornamental, an exotic addition to English gardens. English breeders later shipped it back across the Atlantic to be sold to Americans as a potted plant. At least 75 cultivars, mostly propagated through tissue culture, are available today. Its native range, however, is the eastern United States, extending from southern Maine to Louisiana and northern Florida. A total of seven species are known throughout North America, including sheep laurel (Kalmia angustfolia) and bog laurel (Kalmia polifolia). Along with rhododendrons, azaleas, huckleberries, and Indian pipe, Kalmias are ranked among the Ericacea (heath) family. 

Mountain laurel is the most prolific of the Kalmia species. In the woods, it can grow in dense, gnarly thickets known colloquially in southern states as “laurel hells.” Foresters and lumbermen in Pennsylvania have been heard to curse it with off-color expressions and not-so-nice epithets, the least offensive being “ankle breaker” or “ankle twister.” Mature plants average heights from seven to ten feet, but some specimens have been recorded as tall as 40 feet. Ascending and horizontal branches are often contorted and considered picturesque, and although a shrub, the healthiest of mountain laurels can take on the stature of a small tree. Its growth rate, however, is slow, four to eight feet over the course of a decade. Laurel wood and its burls have been used for various tools and utensils, explaining one of its many monikers, “spoonwood.”

The corymb is the marquee attraction. The fused petals of mountain laurel’s florets are shaped like inverted parasols. They range from near white to a blush of pink, while their corollas include subtle markings that can reveal either cinnamon, scarlet, rose, or burgundy. Like the symmetrical shapes of dancers in a 1930s Busby Berkeley musical, each floret is perfectly formed. From late May to late June, scores of these corymbs appear in one of two stages, bud or bloom.

Governor Gifford Pinchot dubbed mountain laurel the state flower of the Commonwealth of Pennsylvania in 1933. One factor in its designation concerned the shrub being located in nearly all of the state’s sixty-seven counties, but the public’s concern for conservation might have also played a role.

Generations of Pennsylvanians have been admonished by their parents, scout leaders, and camp counselors that it was against the law to pick the state flower. This is not true, according to the Department of Conservation and Natural Resources. There are also no legal restrictions on cultivating Kalmia latifolia, although special permits and inspections from the Pennsylvania Department of Agriculture are required to sell any collected native specimens.  

SOURCE:PSU.EDU