Bradford pear, from beloved to banished – keep a lookout for it!

Partager

0

Bradford pear, or Pyrus calleryana, used to be all the hype in ornamental gardens throughout the United States and Europe. Today, common sense labels it for what it is: an invasive tree that’s dangerous for the native environment!

Where is Callery pear native from?

Bradford pear, a particular cultivar of Pyrus calleryana, comes from seeds bought in Nánjīng (China). Most other cultivars come from seeds and specimens collected in other provinces in China and Korea. These were later cross-bred with other pear tree species and varieties.

When only the Bradford pear cultivar was planted, the tree couldn’t spread naturally. This is because it isn’t self-fertile. At the beginning, landscapers thought it was sterile. It sounded like the perfect ornamental pear!

When new cultivars appeared, however, the massive blooming led to abundant fruit-bearing thanks to cross-pollination. Birds then spread seed everywhere!

In the following map, the green portion shows where Callery pear is native to. There are now many cross-breeds, even with the common pear tree, so it’s sometimes hard to pinpoint the exact variety.

Callery pear region by region: how invasive, and what the law says

The same tree behaves very differently depending on where it has been planted. This table sums up where Callery pear has turned invasive and how each region has responded so far.

Wherever you are, the first useful step is simply knowing whether the tree is already on a local list.

Current range where Bradford and Callery pear grow

In Canada and Europe

Though planted occasionally in urban environments, this particular ornamental pear tree hasn’t yet reached a point where it has turned invasive.

• In Europe, the species isn’t as invasive as it is in the Americas. This is mostly due to more competitive local plants. This is certainly the result of centuries of man-managed landscapes, leaving only the most prolific growers around in natural settings.
• Canada has the tree on its watchlist in certain provinces. However, there isn’t yet any nationwide effort to prevent planting and spread of the species.

In the United States

Reports of Bradford pear and its sister-cultivars are gathered and collated by the University of Georgia EDDMapS project. Here they are, shown down to county level.

You can report these trees if you see them nearby just here.

In Australia

For now, most reports signal presence of Callery pear in the SouthEast of the country, along the coast.

Laws and regulations about Bradford pear

In the United States, local Agriculture offices and government entities produce lists of weeds and noxious invasive species. On the following map, colored states have already written out such laws and regulations. They often involve banning on sale, planting, and reproducing of the tree.