The stench of spring

No comments

By: Kate Luce


Spring is here, and maybe it will finally stick in Northern Indiana. However, with spring comes an unexpected stench in the air. Is it rotting fish?  No, it is the infamous Callery Pear.

The Callery Pear is a small ornamental tree, known for its beautiful – but smelly – white flowers that are now blooming throughout the region. It’s even right here on campus. Near the southside of Wiekamp, these trees are in full bloom. The tree can be found almost everywhere in Indiana, and it’s a popular landscaping choice for many reasons. However, this tree has plenty of downsides. 

“[The] Bradford Pear has several desirable qualities for an urban lawn tree – beautiful spring floral display; glossy, dark green summer leaves; lovely autumn leaf color; modest size with a nice pyramidal to rounded crown; hardy and adaptable to many growing conditions. I’m sure that these were the reasons IU chose to plant the tree. Its downsides have only become evident in the last couple of decades,” professor of Biology, Dr. Andrew Schnabel, said.

While the downside of these trees has only been noted a few decades ago, the impact of this tree should not be taken lightly. 

Indiana’s DNR does not have this tree as invasive but has cautioned Hoosiers on planting these trees. According to a statement published by the DNR in 2019, Hoosiers should avoid planting these trees and should consider replacing them if possible. 

“First, even though it was originally touted as not being very reproductive (few, if any, fruits; mostly self-sterile), it clearly produces fruits.  This happens especially when two different cultivars are planted close to each other and can cross-pollinate. …  Birds are more than happy to disperse these fruits, and in this way, the species has become an aggressive invasive in many of the areas of the Midwest. Invasive species displace native species and reduce the diversity of our plant communities. This has cascading effects up the food web, as it negatively affects the diversity of insect, bird and mammal communities,” Schnabel said.

Another major downside this tree has is that the wood is very weak, Sass and Schnabel both said. This tree is often the victim of storms and winter weather, breaking or tipping over in these conditions. In Northern Indiana, this weather is just part of living in the area.

To combat this, some of these trees have been engineered to strengthen them, but by doing so, these trees became fertile. These trees would sexually reproduce with one another, causing another way for the fruit to spread.

“They’re typically invading areas of old fields and grasslands and prairies. And so they are, they’re displacing native species essentially like, which is what most invasive species do. They’re brought here without any natural enemies. Therefore, they have typically an advantage over the species that have coexisted and evolved in our ecosystem since the end of the last glaciation.       

They’re out competing and pushing out those species. That’s a bad thing for ecosystems when you have something disrupting something that took thousands of years to find a balance,” Steve Sass, chair of the Ecological Advocacy Committee for the Venue Parks and Arts in South Bend, said. 

Their impact is felt even in South Bend. Just off of Nimtz Parkway, these trees have completely overtaken a native grassland area. Near the AMC on Chippewa Avenue, the Callery Pear is found in a small grassland, almost overtaking the other trees.

This tree has peaked the interest of those who work alongside the South Bend City Council. Sass and the Ecological Advocacy Committee, is looking to pass an ordinance that would ban the sale and planting of the Callery Pear, which the DNR has issued a caution on, and other invasive species.

The proposal has been put on the backburner since COVID-19 hit the area, but with normalcy coming into the grasp of the community, this ordinance could be passed as early as April 26. 

The proposal has already been read once to the council. It will take two more readings before it can be voted on.

South Bend would be the first and only city in Indiana to establish this kind of law, Sass said. Knox County in southwest Indiana has a similar rule, but they have banned high and medium threat level invasive species. This leaves out low and even cautionary threats the DNR has brought to light.

“We can by leading by example, perhaps encourage other communities to take the step also, particularly some of our neighboring lands would be nice, because obviously, if we prohibit these things from being sold, it’s a lien on the menards on the south side of South, then people could still go and drive over to Mishawaka. Although it would be technically illegal to plant them in their yard. We know that nobody’s nobody’s going to be enforcing that sort of thing. We’re not going to be going under people’s properties and issuing citations. The idea, really is just to strongly encourage the retailers and the landscapers to stop using and selling these things,” Sass said. 

As of now, shoppers at nurseries can still find these trees, as they are still a popular choice for landscapers and homeowners. However, the DNR is asking to instead plant a serviceberry tree or the Eastern redbud tree.

“I don’t like to recommend that mature trees be removed, but I might be able to be convinced in this case.  There are several better alternatives, and although removing mature trees always leaves a hole in our campus forest, it could be filled relatively quickly with a native species,” Schnabel said.

Leave a Reply