Cincinnati and much of the U.S. has been invaded! No, the invaders are not villains and I am not referring to COVID-19. I am talking about the green, leafy invaders that you can see along almost any hiking path in Cincinnati, Ohio. I have always understood that invasive species are present and affecting local biodiversity but admittedly have not taken the time to identify and research each species. Since invasive species have always been such a prominent visual in my childhood landscapes, they have simply blended into my surroundings. Until now, I have not paid much attention to the sheer volume they take up. Recently, by simply observing and painting my surroundings, I have started to notice just how much of my local ecosystem has been consumed.
In my local hiking and running experience, I noticed three invasive species that I decided to explore including Amur Honeysuckle, Winter Creeper, and English Ivy. Each of of these species can be found in private plots as ornamentals and ground cover. A short description as well as brief treatment guidance for each species is shared below.
- Amur Honeysuckle (Lonicera maackii) was brought to the U.S. from China for use in soil stabilization (Luken & Thieret, 1996). Populations spread quickly via seed dispersal and can grown out of control once they are well established. According to a review of scientific literature, Amur Honeysuckle is able to respond to its environment due to its extended growing season. Additionally, it can prevent germination of surrounding native plants using allelopathic effects (McNeish & McEwan, 2016), making its presence a concerning issue for biodiversity. Removal and restoration efforts are difficult for well established honeysuckle populations. Honeysuckle does increase soil stabilization, so large thickets cannot be removed without proper restoration. If removal is possible, targeted cut stump herbicide treatments, also known as a cut and paint method in which the stem is cut and herbicides are applied to the stem, can be effective in the removal process. In addition, basal spraying involves treating the lower 12 to 18 inches of the stem (Smith & Smith, 2010). It is necessary to spare surrounding native plants during treatments and human protection must always be considered when using chemicals.
- Winter Creeper (Euonymus fortunei) was introduced to the U.S. in 1907 for ground cover use (Zouhar, 2009), and it is still prevalent in privately owned lands today. It presents with densely arranged, leathery leaves that are elliptical in shape and has the ability to cover trees (Zouhar, 2009). The best way to address future invasions is to simply not use Winter creeper in your landscaping. An existing population must be removed by pulling out the vines and stems completely so that regrowth will not occur. Growing vines can be cut back to reduce flower and seed production (Zouhar, 2009).
- English Ivy (Hedra helix L.) is currently not considered to be an invasive species, though it is on a list to be assessed (Ohio Invasive Plants Council, 2018). Like Winter creeper, English Ivy has become a competitive non-native vine due to human use as ground cover in private lots. Leaves of English Ivy can be identified by their pointed lobes and light colored veins. A 2015 study found that a bacterium called B. amyloliquefaciens may form a symbiotic relationship with English Ivy. The study results suggest that the bacterium may promote ivy growth and help to inhibit disease (Soares et al, 2016).
To explore these species on a deeper level, I decided to set out on a few local hikes, map my routes, photograph the invasive species I see, and then participate in some nature journaling as a way to help me remember how to identify each one. The purpose of this blog post is to share my observations and invite you to join in the hiking and nature journaling experience so that we can start a dialogue surrounding local invasive species. I hope this post will simply provide a fun educational experience as well as a platform for you to share how your community is battling these green invaders. And, while COVID-19 continues to force social distancing and cancellations of community events, I hope this activity will also encourage some outdoor adventuring and relaxing watercolor activities. Please share links to any community events such as Honeysuckle Sweeps or scheduled invasive species removal days in the comments section below!
And now, please join me on a quick GoogleEarth virtual tour of three accessible Cincinnati hikes including the paved bike trail at Lunken Airport, International Friendship Park located in the downtown area, and Parker Woods Nature Preserve located in Northside. (Please note that GoogleEarth is not supported by Safari.)
Join me here! VIRTUAL MAP
Now, let’s record what we saw, learn a bit more about each invasive species, and relax with some watercolor painting. Here’s what I recommend using:
Watercolor paper: I recommend ordering Winsor & Newton Professional Watercolor Blocks. I always order the 7” x 10” Cold Press option for smaller paintings and journaling. For most tutorials, I will be using this size. Link: https://www.dickblick.com/products/winsor-and-newton-professional-watercolor-blocks/
Paints: Inktense Paint Pan Travel Set: You can obviously use whatever watercolors you have at home, but this travel set of Inktense products is fantastic for travel and nature journaling. It will last you a very long time. This kit is wonderful for artists of all ages and the colors are incredibly vibrant. Link: https://www.dickblick.com/items/01680-1019/
A pencil and eraser
A micron pen or other inked writing utensil
English Ivy: (Need to make video)
Thanks so much for joining me in this experience! Please share questions, comments, and feedback below and, if you participated in the nature journaling activities, I would LOVE to see your work! Please share photos on Instagram and tag or message @abbynurrewatercolor.
Happy hiking and painting!
Luken, J.O. and J.W. Thieret. (1996). Amur honeysuckle, its fall from grace. BioScience 46:18–24. doi: 10.2307/1312651
McNeish, R. E. & McEwan, R. W. (2016). A review on the invasion ecology of Amur honeysuckle (Lonicera maackii, Caprifoliaceae) a case study of ecological impacts at multiple scales. The J. of the Torrey Botanical Society, 143(4), 367-385. Retrieved from https://bioone.org/journals/the-journal-of-the-torrey-botanical-society/volume-143/issue-4/TORREY-D-15-00049.1/A-review-on-the-invasion-ecology-of-Amur-honeysuckle-Lonicera/10.3159/TORREY-D-15-00049.1.full#i1095-5674-143-4-367-Deering1
Ohio Invasive Plants Council. (2018). List of Plants to Assess. Retrieved from https://www.oipc.info/plants-to-assess.html
Smith, K. & Smith, A. (2010, Aug. 16). Controlling non-native invasive plants in Ohio forests: bush honeysuckle. Ohioline: Ohio State University Extension. Retrieved from https://ohioline.osu.edu/factsheet/F-68
Soares, M. A., Li, H., Bergen, M., Manoel da Silva, J., Kowalski, K. P., & White, J. F. (2016). Functional role of an endophytic Bacillus amyloliquefaciens in enhancing growth and diseases protection of invasive English ivy (Hedera helix L.). Plant & Soil, 405(1/2), 107-123. doi: 10.1007/s11104-015-2638-7
Zouhar, Kris. 2009. Euonymus fortunei. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: https://www.fs.fed.us /database/feis/plants/vine/euofor/all.html [2020, April 15].