With so much rain falling across the Buckeye State in recent weeks, urban and woodland landscapes are looking extremely lush. A casual glance at the flower garden reveals healthy plants, many loaded with vibrantly colored blossoms.
But beware, there may be aliens lurking among your beloved boxwoods and delicately scented lavender. Seemingly innocent plant species, such as the aggressive garlic mustard, can quickly become the centerpiece of your garden if not weeded out.
Approximately one-fourth of the plants growing in Ohio originated in other states or countries. These species are called non-native, exotic or alien because they were not known to grow in Ohio prior to substantial European settlement around 1750.
Some invasive plants arrived in Ohio by accident, while others were introduced for agricultural purposes, medicinal and horticultural use, erosion control, forage crops or as food for wildlife. Some alien plant species, such as the teasel, may have been brought by early settlers to remind them of home. Often used today in dried floral arrangements, the teasel is an aggressive exotic that has the capacity to take over prairies and open grasslands.
Around 3,000 plant species are growing in our state and more than 700 are non-native. Of that number, nearly 100 are causing problems at Ohio outdoor facilities, including nature preserves, state and metro parks and wildlife areas.
So, whats the problem with foreign plants? These alien invaders out-compete native plants for space and resources within the ecosystem. Ultimately, they completely displace Ohios indigenous plants, changing the balance that thrives between our native species and the environment.
Wildlife is also negatively impacted by the loss of indigenous plant life. As invasive species squeeze out vegetation, they destroy natural cover and food for wildlife. Purple loosestrife, for instance, has invaded many of Ohios wetlands, but provides little value to wildlife. Wetland birds depend on insects as a food source and this broad-leaf perennial attracts few insects to feed on it.
Sometimes we plant invasive alien species for landscaping or wildlife habitat without realizing the problems we have caused. You can help Ohios environment by avoiding some of these more common non-native invaders: bush honeysuckles, buckthorn, garlic mustard, purple loosestrife, reed canary grass and autumn olive.
Landscaping with native plants is fun, interesting and conservation friendly. Native species are well-adapted and often survive with less care than non-natives. They are also better suited to providing natural forage and habitat for wildlife.
If you discover an alien species in your landscape, it is best removed while the plants are still immature and if possible before they have flowered. Eradication methods include physically removing the plant (root and all) and herbicidal applications. Biological control is another method that uses the natural enemies of the invasive plant species to reduce its population.
For more information on invasive plants and a list of alternative plant species you can safely plant in your landscape, contact the Ohio Department of Natural Resources Division of Natural Areas & Preserves at (614) 265-6468.