Did you see the teal-blue stuff sprayed on the vegetation next to I-695 between Timonium and Pikesville last week? It was a little weird, but also sort of pretty as every square inch of area next to the highway was blasted with the teal-colored gunk. The blue spray is a non-toxic fertilizer designed to jumpstart native grass growth. Since 2012, Maryland’s State Highway Administration has been eliminating the invasive plants choking our ‘roadway gardens,’ and replacing them with native plants.
Invasive plants are from other regions, but make their way into our soil. When driving, you can’t miss those huge swarms of vines (mile-a-minute weed) engulfing entire forests. There are so many invasive species in Maryland that the National Park Service publishes a 150-page guide on identifying and eliminating the bad boys. And bad invasive plants have no local predatory bugs or systems to stop them from snuffing out everything local in their path.
For the past five years, Maryland’s State Highway Administration (SHA) has been focusing on eradicating invasive species because federal funding became available. The mile-a-minute weed and the Tree of Heaven tree are two of about ten species the SHA maintenance teams have chopped down along our state roads and replaced with native plants and grasses. The teal-blue fertilizer used on I-695 is part of the preventative maintenance contract to keep I-83 (Jones Falls Expressway) between the Baltimore City line to I-695, and along the west side of I-695 from I-95 on the Arbutus side to Pulaski Highway, free from further invasive plants, and also to promote grass growth.
You may ask: Why would the SHA spend cash on plants instead of the roadways?
Certain species, like the Tree-of-Heaven from Asia, have weak root systems and easily fall into highways during storms. Invasive plants also crowd out Maryland’s native plants that provide room and board for wildlife and birds. Native plants also help manage stormwater.
Charlie Gischlar of Maryland’s SHA shared that about another $12 million will soon be invested on ridding our state’s “highway gardens,” of invasive species, and replacing them with native flora and fauna.