Why do sunflowers grow on the side of the road? - Ask Extension
I always see sunflowers growing on the side of the road! But not really anywhere else! This made me think that they have some sort of adaptation that ...
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Why do sunflowers grow on the side of the road? #478732
Asked August 16, 2018, 4:28 PM EDT
I always see sunflowers growing on the side of the road! But not really anywhere else! This made me think that they have some sort of adaptation that makes them better at surviving the stresses that come along with living next to a road! Does anyone know what specifically allows them to outcompete other plants near the road?
Jefferson County Colorado
Expert Response
Hello,
The roadside Sunflower (Helianthus annuus) is a North American native annual plant that has a wide range of tolerance for soil and moisture conditions. I have found two explanation why they appear to be more prevalent on roadsides than in open fields:
Best regards,
The roadside Sunflower (Helianthus annuus) is a North American native annual plant that has a wide range of tolerance for soil and moisture conditions. I have found two explanation why they appear to be more prevalent on roadsides than in open fields:
- Roadsides have been more recently 'disturbed' during the construction of the road, as compared to adjacent fields. All kinds of seeds germinate in the disturbed soils, and sunflowers are good competitors for light, due to their height. http://bioweb.uwlax.edu/bio203/s2008/mitchell_sara/Habitat.htm .
- In areas that are grazed, fences prevent herds from feeding on plants along the roadsides http://wildlifehabitat.tamu.edu/mgmtplan/appendixw.pdf.
Best regards,
