It was a long way away, beside a brick house in a well-kept subdivision, but the trees rose above a wooden fence, displaying everything that had made the Bradford pear so appealing: they were towering and robust and, during the early spring, they were covered in white flowers that turned their limbs into perfect clouds of cotton.
The same white flowers were blooming uncontrollably in a thicket of tangled branches and thorns when David Coyle, a professor of forest health at Clemson University, pulled over in his pickup truck. He could see the monster those trees had spawned: a forbidding jungle that had consumed an open lot nearby, and where the same white flowers were blooming uncontrollably in a thicket of tangled branches and thorns.
‘Once this tree starts growing someplace, it doesn’t take long for it to take over the whole environment,’ Professor Coyle, a specialist on invasive species, said. “It simply completely wipes away everything below it.”
The Bradford pear was the tree of choice in the 1960s, when suburban sprawl spread throughout the South, clearing land for labyrinths of cul-de-sacs and two-car garages. Bradford pears were the trees of choice in the 1970s, when suburban sprawl spread across the South. You could find them practically everywhere, they could grow in virtually any soil, and they had a pleasing form with mahogany-red leaves that lasted far into the autumn and flowers that bloomed early in the spring.
The popularity of the trees increased dramatically during a period of transition, when millions of Americans relocated in search of the comfort and order that suburban areas were meant to bring. “Few trees possess every desirable characteristic,” The New York Times’ gardening pages remarked in 1964, “but the Bradford ornamental pear gets uncommonly near to the ideal.” The Bradford ornamental pear is a kind of pear that is native to the United States.
Despite all of the promise, the trees turned out to be an unwieldy nuisance, one that has vexed botanists, homeowners, farmers, conservationists, utility companies, and government officials across a growing swath of the country, extending from the East Coast to Texas and the Midwest and affecting a growing number of people.
In South Carolina, the battle has become more intense. The state is now in the process of prohibiting the sale and trading of the trees in question. Professor Coyle, who records invasive plants and insects that have made their way into South Carolina and works to restrict their impact, has set up “bounty” programmes in which individuals who bring in proof of a downed tree are given a native replacement in exchange.
At first glance, the Bradford pear’s disadvantages seemed to be inconsequential. Its white blooms, as lovely as they were, had a foul stench that smelled nearly fishy, despite their appearance. However, as the trees grew older, more and more negatives began to appear. In storms, they had a weak branch structure, which made them more prone to cracking and tumbling, sending branches crashing through power wires, into pavement, and onto the roofs of the houses they were intended to be beautifying.
The Bradford pear is a cultivar of the callery pear, which means that it is a variation that has been developed via selective breeding – in this instance, by developing a tree that did not have the thorns of some other types and did not get infested with pests.
However, in South Carolina, industry executives said that researchers persuaded them that there were viable alternatives available. Furthermore, the selection was made simpler due to the fact that Bradford pears had fallen out of favour as a landscape tree. According to Mr. Rogers, who is also the president-elect of S.C. Green, an industry body, “that factory has been in decline for a very long time.”
Nonetheless, state authorities and households are left to deal with the plethora of Bradford pears that were planted in previous years. Professor Coyle flew to Columbia, South Carolina’s state capital, on a Saturday last month to participate in the latest in a series of reward exchanges that he has arranged around the state.
There were dozens of potted native trees on a flatbed trailer, including Shumard oak, yellow poplar, persimmon, Eastern red cedar, and sweet bay magnolia, to name a few. Professor Coyle observed that the trailer was positioned in the shadow of a Chinese pistache, which is another nonnative species.