Beautiful flowering tree seen across Ohio causes ugly invasive problem

On Mar 31, 2022

A beautiful tree is causing a problem so ugly a state law has been developed to deal with it.The Callery pear tree is in full bloom and easy to spot along about any local roadway because of its brilliant white flowers, but they’ve become a beautiful problem.“They’re very attractive and that’s why people really love them,” said University of Cincinnati biologist Dr. Theresa Culley.The Callery pear tree is now on the invasive species list.“That’s one of the interesting things about invasive species. There’s always a story behind it,” Culley said.Culley was among the first to understand the problem.The Bradford pear tree was the original flowering pear to come to the east coast. It came from China in the early 1900s.Every Bradford pear has the exact same DNA. It doesn’t reproduce.The Bradford had a problem. It was weak and broke easily.So, new varieties also called new cultivars were developed that were stronger.“The problem is that these different cultivars are able to cross-pollinate,” Culley said.Many of the cross-pollinated Callery pears started cropping up, they have started choking out native species. Getting rid of the trees is very difficult.If they’re cut down, they can grow back from the root. Even if a bulldozer takes the tree out, seeds falling from the tree can remain in the ground for 11 years and become a tree.Researchers believe the tree may even emit a chemical that makes it difficult for any other species to come up around it.Since the Callery pear was put on the invasive species list, there is now a law that will make the sale or distribution of the tree illegal in Ohio beginning in January.

CINCINNATI —

A beautiful tree is causing a problem so ugly a state law has been developed to deal with it.

The Callery pear tree is in full bloom and easy to spot along about any local roadway because of its brilliant white flowers, but they’ve become a beautiful problem.

“They’re very attractive and that’s why people really love them,” said University of Cincinnati biologist Dr. Theresa Culley.

The Callery pear tree is now on the invasive species list.

“That’s one of the interesting things about invasive species. There’s always a story behind it,” Culley said.

Culley was among the first to understand the problem.

The Bradford pear tree was the original flowering pear to come to the east coast. It came from China in the early 1900s.

Every Bradford pear has the exact same DNA. It doesn’t reproduce.

The Bradford had a problem. It was weak and broke easily.

So, new varieties also called new cultivars were developed that were stronger.

“The problem is that these different cultivars are able to cross-pollinate,” Culley said.

Many of the cross-pollinated Callery pears started cropping up, they have started choking out native species. Getting rid of the trees is very difficult.

If they’re cut down, they can grow back from the root. Even if a bulldozer takes the tree out, seeds falling from the tree can remain in the ground for 11 years and become a tree.

Researchers believe the tree may even emit a chemical that makes it difficult for any other species to come up around it.

Since the Callery pear was put on the invasive species list, there is now a law that will make the sale or distribution of the tree illegal in Ohio beginning in January.