MDOT sunflower planting serves as successful food source for pollinators while fighting invasive species

Contact: Jocelyn Hall, MDOT Office of Communications,
Agency: Transportation

October 11, 2016 – The Michigan Department of Transportation (MDOT) recently partnered with the Saginaw County Conservation District (SCCD) to complete a sunflower planting along the I-75/M-46 interchange in Saginaw County. The planting was completed as part of a pilot program researching the use of sunflowers in the MDOT right of way (ROW) to support pollinators, while also aiding herbicide treatments used to choke out invasive species. Frequent drivers of the I-75/M-46 interchange may have noticed the thick rows of sunflowers inside the loop ramps on the north side of the interchange. With assistance from SCCD, the planting was completed in late spring and began to bloom in August.

This pilot location was chosen based on its soil and site conditions. MDOT had been treating the site recently for several invasive species including Japanese knotweed, phragmites and teasel.  The hearty nature of sunflowers makes them an ideal planting to help shade out invasive species and other weeds, after a period of establishment. This pilot was modeled after a similar practice by the North Carolina DOT, who has used sunflower plantings along their ROW for years. When considering a sunflower planting, several factors were heavily weighed. The planting would need to require minimal maintenance, fit the site conditions, and survive in the tough ROW environment. Sunflowers were selected because they would also act as a food source for pollinators. Two species of sunflowers were planted at the interchange, both known to be an attractive food source for bees. In an effort to combat the nationwide pollination crisis, the USDOT now requires all state DOTs to actively use pollinators in landscaping plans, where possible and practical. This includes the use of flowers and trees known to serve as a popular food source for pollinators.

MDOT currently has plans to redesign the interchange in 2018, making this particular location an ideal spot to research the use of a low cost annual planting. MDOT plans to complete an annual planting in this interchange each year until the future construction project begins, continuing to provide a reliable food source for pollinators over the next few years. Landscaping plans for the interchange redesign are already underway, and will incorporate permanent wildflower plantings. The wildflower planting will be virtually self-sufficient after just a few years of cultivation, and will also continue supporting pollinators across the Bay Region.

MDOT Bay Region Resource Analyst Amanda Novak predicts year two of this project will lead to an even more successful outcome, and further support the pollination effort. “To date the sunflower planting was as successful as I had hoped. It was feeding many bees this fall, when the other food sources tend to drop off,” said Novak. “We appreciate the partnership with the SCCD, and we look forward to continuing to work with them on this initiative in the future.”

MDOT Sunflower planting

Photo Caption 1: A thick row of sunflowers bloomed inside each loop ramp
on the north side of the I-75/M-46 interchange, starting in August.