David Fairchild introduced a mind-bogglingly large number of plants to the U.S., changing the country’s farms and botanical gardens forever.

Born on this day in 1869, Fairchild became a botanist at a time when the American government had an unprecedented interest in species from around the globe. His work with the USDA, as the head of the Office of Seed and and Plant Introduction, and his private collection created a network of extraordinary richness. But it also helped to create ecological disasters caused by invasive species.

Fairchild’s career was full of global adventures and quests, writes Marjie Lambert for the Miami Herald. He or his team “introduced such success stories as the Meyer lemon, soybeans, Calimyrna figs, date palms, durum wheat, navel oranges, and many varieties of mangos and avocados to American farmers,” Lambert writes. “He had a role in bringing the first cherry trees to Washington D.C.”

By the end of Fairchild’s career, according to Lambert, his office had introduced 111,857 new species to the U.S. It was a grand testament to the United States’ richness and new twentieth-century openness to the world. And the introduction of such diversity reassured those concerned that the domestic food supply could be easily wiped out by one disease, drought or insect. His private collection was vast, and the botanical garden that bears his name has a rich collection of plants from around the world.

Among other things, Fairchild hoped that his work would bring new beauty to the American landscape, writes Jenny Staletovich, also for the Herald. According to one 1945 entry in the garden’s log, she writes, “Fairchild hoped his mangroves would one day ‘brighten our coasts with their flowers.’”

“Several decades later, botanists cringe at the thought,” she writes. The long-term impact of Fairchild’s work hasn’t all been good, writes Don Evans, a former director of grounds management at the Fairchild Tropical Botanic Garden. In South Florida, where Fairchild was active throughout his life and eventually retired, the seeds of his work are still spreading… and spreading… and spreading, where people don’t want them to.

Take the two species of mangroves that are associated with Fairchild in southern Florida—one that he planted at his home and one that was planted by the botanical garden. “For decades, the trees flourished, showcasing the flowery beauty of exotic mangroves,” Staletovich writes. “But at some point, something bad happened. They escaped.”

Mangroves are coastal species that are found in salty environments around the world. More than 50 species exist, according to the Florida Department of Environmental Protection, of which three are native to the state–the red mangrove, the white mangrove and the black mangrove. The species provide a number of benefits to coastal Florida, the department writes, including helping to prevent erosion with their root networks, protecting uplands from storms and floods, and purifying water and air.

But Florida’s mangroves are endangered, and the invasive species that have entered the ecosystem are no help, writes Stalenovich. They compete with the native white mangrove, but don’t have the adaptations that support them thriving and sustaining other life in the functioning coastal ecosystem.

While the behavior of the invading mangroves is unprecedented for that species, “It’s far from the first time that exotic plants have climbed garden walls to threaten native ecosystems,” she writes. This behavior has caused botanical gardens across the country to change the way they view their specimens, she writes.

Where once they collected without thought for the consequences to native species, they now do risk assessments on species that might spread and destroy them if necessary—even if the plants have historical value, like the mangrove Fairchild planted. “Sometimes the tough choice has to be made to do away with a species that has been a favorite ornamental or has had special interpretative value,” Evans writes. “Our responsibility to the local and global environment demands that these tough choices be made.”