For those who suffer from seasonal allergies, the onset of spring can be a bittersweet time.
In recent years, it seems allergies in the US have been getting worse and worse – and, experts say urban landscaping practices may be to blame.
A bizarre phenomenon known as ‘botanical sexism’ may be driving pollen ‘overdoses’ in cities across the country.
Over the past few decades, landscapers have been increasingly planting male trees and plants, due to their ‘litter-free’ nature, meaning they don’t shed seeds, fruits, or pods.
But, what male trees lack in messy seeds, they make up for in pollen.
‘The problem is that while these trees and plants are “litter-free,” they all produce abundant allergenic pollen,’ Ogren explains, of male trees. Above, male begonias are pictured (file photo)
This is according to horticultural expert Thomas Leo Ogren, who first began searching for pollen-free plants for his yard a few years back to help alleviate his wife’s allergies, according to MNN.
In doing so, Ogren found his city was dominated by male plants.
The influx of male plants startd after the mid-1980s, when millions of city trees were wiped out by Dutch elm disease, the expert explained in a 2015 op-ed for Scientific American.
Based on recommendations from the universities, cities around the US began planting clonal male trees to replace those that had died.
‘The problem is that while these trees and plants are “litter-free,” they all produce abundant allergenic pollen,’ Ogren explains, of male trees.
And, as they get bigger each year, they release more pollen.
To fight the issue, the expert urges landscapers to and local growers to use more female trees.
He’s even developed an online tool called the Ogren Plant Allergy Scale (OPALS) to rank common plants.
In recent years, it seems allergies in the US have been getting worse and worse – and, experts say urban landscaping practices may be to blame. A bizarre phenomenon known as ‘botanical sexism’ may be driving pollen ‘overdoses’ in cities across the country. File photo
As Ogren explains, much of the allergy issue originates right in your backyard.
‘Despite what we often read about pollen blowing in from hundreds of miles away, in fact most pollen lands and sticks quite close to where it is shed,’ Ogren explained.
‘The greatest amount of pollen from a large tree will normally land within 20-30 feet from the dripline of the tree itself.
‘This translates to what is known as “proximity pollinosis” or allergy that is triggered by the planets closest to where we live, work, play or go to school.
‘Almost all urban allergies now come directly from the planted landscape – they are homegrown.’