Winter Invasive Plant ID at Turtle Cave in Athens, Ohio - Honeysuckle, Multiflora Rose, and Privet

            For New Year's Day, 2024 I was lucky to have a partner and dog willing to put up with some winter nippiness and muddiness to hike a nearby trail that promised a cave at the end. While there, I documented several things including the abundance and distribution of invasive plants, the plants with wild bonsai ("yamadori") potential, the details of the natural deciduous deadwood decay patterns here in Ohio, and some rock formations that were interspersed in the forest. In today's article, I share the observations from there focused on Ohio invasive plant identification ahead of our upcoming CBS invasive digs. In the near future, I'll follow up with more pictures from the other observations.

Sections:

I. Invasive Plants in Ohio
    IA. Why do invasive plants matter?
    IB. History of Columbus Bonsai Society's involvement with invasive plants
    IC. CBS INVASIVE Alliance (see previous post)

    ID. Invasive plants at Turtle Cave in Athens, Ohio - Winter Identification

        ID1. Invasive Japanese (Vine) Honeysuckle

        ID2. Invasive Multiflora Rose

        ID3. Invasive Shrub Honeysuckle

        ID4. Invasive Chinese Privet

Blog/Central Ohio Bonsai Announcements:

1. I now sell pure pumice and pumice-pine bark pre-mixed bonsai soil in central Ohio. Check out here for more information and prices. This is the mix I make and use for myself to good results with my trees!
2. CBS Club Dig Days for 2024 are out! - See the list and RSVP here to be sent the addresses of the events. Options include 4/6, 4/13, and 4/14/2024. All are welcome. Contact me with any questions.
3. See my recently published lecture - "Introduction to Wild Bonsai in Ohio and Beyond" for some tips on how to get started digging yamadori.

With the density of these privet berries, it's easy to see how they can invade our forests! If you look closely you will also see an invasive Japanese Honeysuckle vine still hanging onto its leaves.

I. Invasive Plants in Ohio

IA. Why do invasive plants matter? What's their impact on the environment and ultimately on all of us?

            You might have heard it said that invasive plants are harmful because they occupy physical space and use water and fertilizer from the environment that native plants could use. But, due to the interconnected nature of biology, the problem runs much deeper than that. Regarding why invasives are so successful and why native plants struggle because of them there are a few factors to consider first. YES, it's true that invasive species often multiply abundantly because they have no natural predators in their new environment. It's also true that their competitors aren't adapted to the presence of competing invasives and long-lived organisms like trees will have a harder time evolving in response to local changes. Lastly, invasives/non-native organisms can bring pests and diseases that related native plants aren't adapted to defend against like the chestnut blight which has nearly driven the American chestnut to extinction or the emerald ash borer which has killed 99% of mature ash trees in the most affected regions of the US. Each instance of an invasive taking over has a myriad of consequences both to the natural world and how humans are able to utilize species and spaces involved.

            The problem of invasives has cascading effects also in terms of the global biodiversity crisis. You may or may not have heard of this as it gets less press than climate change but globally within the last 50 years there has been a 64% drop in wildlife and in some sectors, it has been as high as 94% depending on the group of organisms and region. There's much more to be said on this topic but just be aware that the loss of wildlife is happening everywhere and at every level of the tree of life. Some scientists even consider the era we are living through to be the 6th mass extinction event in the history of the world due to the rate that species are going extinct. This would mean mankind has been as destructive to nature as the meteor that took out the dinosaurs! Ultimately this loss of species impacts us in ways big and small both predictable and unexpected. We rely on natural systems working properly to provide pollinators for many crops, to provide a stable climate, to provide timber for construction, to provide fish to eat, and even as a source for medical drug discovery.

            So how do invasive species tie into this crisis? Within regions, invasive species and diseases are responsible for 10-20% of the loss in biodiversity. So let's talk about how invasive plants impact the whole food web now. Say a wooded lot full of a native ecosystem gets clearcut for development and only non-native and invasive plants are put back in. That amounts to a considerable loss of habitat and food first and foremost for insects. The podcast "Growing Greener" turned me onto this fact but apparently, insect relationships with host plants are highly specific! Many species of insects eat and live within only a handful of species of plants. Thus if those plants are no longer in the environment or much less abundant, then the insects are much less abundant, and then there are fewer flowers for the bees to collect pollen from, many fewer caterpillars for birds to eat, and so on. There are also further unexpected consequences. For instance, invasive plants often inhibit the growth of native plants by chemically altering soil. Honeysuckle debris which decays in streams was also found to alter the water chemistry to negatively impact the development of the invertebrates there, which then means less abundant fish as they have less food. Oh, what a complicated web we weave.

IB. History of Columbus Bonsai Society's involvement with invasive plants.

            As described previously, CBS' invasive club digs started out as a search for public land that would permit the club access to remove unwanted plants so we could teach others on how to dig wild plants for bonsai. Luckily invasive honeysuckle make striking bonsai subjects, are abundant, and are hard to kill! So they're great for people to learn on. We have done club dig events in 2023 and 2024 and I hope the tradition can carry on in some capacity even if I'm not always with the club in the future.

IC. Announcing the CBS INVASIVE Alliance

            As described in the previous post, this year we are transitioning away from public land to private land. The goal is to revisit the same properties over multiple years so we can keep the invasives at bay and, while the native plants are improving their regeneration, we will be able to access some native species for bonsai as well through these relationships. RSVP here. Landowners can also contact me to get on the list.

ID. Invasive Plant ID from Turtle Cave, Athens, OH, USA.

            When removing invasive plants, it's a good idea to study them enough that you can recognize what is what. In some cases, there are native look-alike plants, so searching online for regional sources of information is always advised! Sometimes the native plants are more rare which helps with regards to the odds being that you will correctly ID the invasive plants, but by the same token, you don't accidentally want to rip out a whole population of rare native plants by mistake. In the future, I'll try to put together my own guide on the local invasives in Ohio, their impacts, identifying traits, and details on native look-alikes and their differentiation. There are species-by-species sources out there that have this information but not all in one place so far as I have found yet.

Note: Botanical identification of plants depends on many factors! THE BEST factors tend to be flowers and fruits, but leaves and branch patterns are often relied upon also. In winter we will have to go by size, texture, buds, and perhaps old leaves/fruits still hanging onto the plant. That does make winter ID more tricky!

            ID1. Invasive Japanese (vine) honeysuckle.

        Information on identifying the Japanese vining honeysuckle can be found here. The older ones get a flakey bark like the shrub honeysuckle does. There is not much in the way of native look-alikes, but in winter, an older specimen could be confused with the American trumpet vine which also develops flakey bark. The leaves are very different though.

A young Japanese honeysuckle vine. Note the leaves. When they grow old they also develop flakey bark.

            

ID2. Invasive Multiflora Rose

            More information on identifying the Multiflora rose can be found here. It's most abundant in forest edges but is commonly found (although less dense) within forests all over Ohio. The hairy leaf stipule is a critical trait that distinguishes this from the native look-alike swamp rose, see here, also has a pink flower vs the white of multiflora rose). I actually didn't know about that look-alike at first so I'll take a closer look in the future! In the picture below you may barely see it where the upright leaf is attaching to the branch (that's the stipule).

Multiflora rose. Barbed branches and distinct compound leaves make it clearly a rose.

ID3. Invasive Shrub Honeysuckles and Distinguishing Native Counterparts

            More information on identifying the invasive species of shrub honeysuckle is found here. Native look-alikes are not found in Ohio according to some sources but in other parts of the country, they are distinguished by having opposite leaves which fuse together at the base of the branch where they attach. This is the main species our original CBS invasive digs focused on due to its sheer abundance in Ohio's woods especially near urban areas. More examples of it in our woods can be seen here and here, and as bonsai here.

They are usually understory shrubs and trees in the forest, but if given full sun and enough time they can develop into full-size trees. Note the cream bark on the trunk and twigs.

Note the buds which attach to the branch directly opposite one another.

Note the cream bark develops a flaky-ness on older specimen.

ID4. Chinese Privet

            Lastly among those invasives I found at Turtle Cave in Athens, OH, we have the Chinese Privet (go here for more information). This one is starting to increase in abundance in Ohio but is not yet as widespread as some of the others I listed above. There is no native privet look-alike to my knowledge so if you see anything with the features described here, feel free to hack it back and/or dig it up for bonsai! This species is actually a pleasure to work with as it develops quickly when bonsai techniques are applied and it is especially quick to develop a thick, ramified/dense canopy which is why it is popular as hedgerow material. I have shown pictures of my own privet bonsai in several previous posts here.

            In Ohio, Chinese privet tends to be a small shrub, but further south in warmer temperatures its invasion is a big problem and they achieve much greater size. The main traits are oval, narrow leaves, smooth white bark, purple berries, and opposite branching. Once you know it you can't unsee it!

Smooth whiteish bark.

Berries hanging on in winter.

Opposite branching.