The Black Hawk County Road Department is busy this spring maintaining county roadways through the Roadside Vegetation Management Program. Along with weed control, they work hard to plant native prairie grasses that will provide a clean, healthy habitat for all county residents, including wildlife.
Recently the crews have been cleaning ditches and seeding native prairies. The prairie mix they use is a diverse mix with over 50 species of forbs and grasses. They seed at a rate of 15lbs native grasses per acre and 5lbs forbs per acre, which is a higher rate because in the spring they know they will lose some seed due to rain, wind, and predation (birds, bugs, and small mammals) of the seed. We will also add about 1 bushel of cover crops per acre along with the native seedings, to reduce erosion before the native planting gets established.
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n the photo on the left, the Roads crew was using oats as a cover crop at 35lbs/ac. After the seeding, the crew applies hydro-mulch over the top of the native seeding to protect it from the heavy rain and high winds that are possible in the spring, it also helps keep the seed in one place and lessens erosion as well.
After the seeding is planted, the Roadside Management crew will monitor its growth and for any undesirable weeds that will grow in the seeding. When the seeding areas get to approximately knee height, they will be mowed down to about 8 inches high. This is done twice during the season to allow the native seedlings that are shorter than the weeds some sunlight for them to grow deeper roots and thicker. This is one of the most crucial parts of establishing a native prairie.
Then in the third, fourth, or fifth year of the seeding, the crew will do a prescribed burn to help get rid of the dead plant material “duff layer” and enhance the response of the native plants to grow as some to most of the native plants need fire to break down seed coats. Getting rid of the duff layer exposes the seed to the sun sooner in the spring to get it growing. Prescribed fire is also used as a weed and tree management tool as most species can’t tolerate the heat of the fire and will die.
A great way to remember the process of prairies seedings is:
- In the first year, the seeds sleep – meaning very little prairie growth will happen and it will look like a weed patch
- In the second year it creeps - you will start to see some native grasses and forbs growing
- In the third year, it leaps- the prairie is thriving and looks fuller with grasses and forbs present.
To learn more about the Roadside Management Program check out the Integrated Roadside Vegetation Management page on the Black Hawk County website.