A Prickly Problem

As Shakespeare’s Juliet noted, a rose by any other name would smell as sweet. But a thorn by any other name would prick just as painfully, and roses aren’t meant to grow everywhere. The invasive multiflora rose (Rosa multiflora) is a species whose lovely white flowers distract from its harmful effects on Fox Island’s habitats.

The fruit of the multiflora Rose. (Photo by Nathan Arata.)

The fruit of the multiflora Rose. (Photo by Nathan Arata.)

Multiflora rose is a vining shrub that is shade tolerant. That means it doesn’t need a lot of sunlight to grow, and it generally grows up onto other plants. Multiflora rose is also a monoecious plant, which is a fancy way of saying that can self-pollinate and it doesn’t need other members of its species to reproduce. One plant can make hundreds of thousands of seeds every year. And those seeds are contained in red berries that are easily consumed and dispersed by animals.

Multiflora rose is a significant problem not just at Fox Island, but also in other Indiana parks and preserves. Just like other invasive species like autumn olive and Japanese honeysuckle, you can find it growing in areas frequented by people: disturbed areas, at the edges of forest habitats, and along trails and roads. It grows thick. It was introduced from Asia in part for its flowers, and in part for its ability to form dense, impenetrable barriers.

The thorns of the multiflora rose are sharp. (Photo by Nathan Arata.)

The thorns of the multiflora rose are sharp. (Photo by Nathan Arata.)

It is hard to walk far in Fox Island without encountering multiflora rose. And it’s these walking encounters that can become a “thorny” issue. The stems of multiflora rose sprawl out in all directions. For plants that grow near trails, those stems will often extend into the middle of the trail. Since the vines are covered with thorns, walking into them on trail can be a painful experience! According to Fox Island naturalists, encounters with multiflora rose are one of the things they worry about most when school groups visit.

How will you know if you’re looking at multiflora rose? Look for those white flowers in late spring, those irresistible (for forest animals) red berries, and of course those long, thorn-covered stems. You are most likely to see multiflora rose at Fox Island along trails, roads, and at forest edges near the prairie and Bowman Lake.

Have you seen multiflora rose in Fox Island? Comment below and let us know when and where you saw it. And contact the park staff to see how you can get involved in removing it!

 
A multiflora rose stem says “you shall not pass!” (Photo by Nathan Arata.)

A multiflora rose stem says “you shall not pass!” (Photo by Nathan Arata.)

 

References

Ecological Landscape Alliance. (2019, March 20). Multiflora Rose: An Exotic Invasive Plant Fact Sheet. Retrieved from https://www.ecolandscaping.org/07/invasive-plants/multiflora-rose-an-exotic-invasive-plant-fact-sheet/

Hilty, J. (2017). Multiflora Rose. Illinois Wildflowers. Retrieved from https://www.illinoiswildflowers.info/weeds/plants/multiflora_rose.htm

Interagency Taxonomic Information System. (2019). Rosa multiflora. Retrieved from https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=24833

Ormiston, J. (2019, April). Personal interview.

Whack-a-mole, Plant Edition

Invasive Japanese honeysuckle (Lonicera japonica) is a BIG problem at Fox Island. You’ll see it growing almost everywhere. It’s especially common in disturbed areas, at the edges of forest habitats, and along trails and roads. That means you’ve probably seen it all over the park.

Honeysuckle and other invasive plants can block sunlight for other plants. (photo by Nathan Arata.)

Honeysuckle and other invasive plants can block sunlight for other plants. (photo by Nathan Arata.)

Japanese honeysuckle itself is a vining plant species that grows up, on, and around almost anything. As its name suggests, it is originally from Japan. It was introduced to the United States as an ornamental plant over a hundred years ago. Its white, sweet-smelling flowers made it popular in gardens and landscaping. Its berries make it even more popular for many local animals, especially birds and small mammals. The seeds are easily dispersed and this has caused Japanese honeysuckle to become widespread.

So if you want to identify honeysuckle, what are you looking for? Honeysuckle is a vining plant. That means it generally grows up onto other plants. You’ll probably see honeysuckle growing densely. This can be a huge problem because honeysuckle doesn’t allow a lot of light to pass under it, and it will often grow so fast and so thick that it chokes off the plants that it grows over.

The leaves of the honeysuckle are opposite and oval-shaped, and they can be a few inches long. They are deep green both on top and underneath. (Non-invasive honeysuckle species may not have the same coloration.)

The leaves of honeysuckle are alternate and ovate. (Photo by Nathan Arata.)

The leaves of honeysuckle are alternate and ovate. (Photo by Nathan Arata.)

Japanese honeysuckle, like many of the invasive plants found at Fox Island, can be difficult to remove. Cutting it down is not enough. The roots also need to be chemically treated to make sure it doesn’t grown back. In fact, just cutting down honeysuckle can caused multiple new stems to grow back and effectively turn the plant into a shrub, making it even harder to remove it on the next attempt. (Japanese honeysuckle is also known as Asian bush honeysuckle because of it can also grow as a shrub.)

You are most likely to see Japanese honeysuckle at Fox Island near forest edges, along trails, and around the park boundaries. Some of the largest honeysuckle plants can be found west of Bowman Lake.

Have you seen Japanese honeysuckle in Fox Island? Comment below and let us know when and where you saw it. And contact the park staff to see how you can get involved in removing it!

References

Haley, N. (2019). Personal interview.

Interagency Taxonomic Information System. (2019). Lonicera japonica. Retrieved from https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=35283

Ormiston, J. (2019, April). Personal interview.

Painter, T. (2017, November 21). How do I Identify Japanese Honeysuckle vs. American Honeysuckle? Hearst Newspapers. Retrieved from https://homeguides.sfgate.com/identify-japanese-honeysuckle-vs-american-honeysuckle-91276.html

University of Florida. (2019). Lonicera japonica. Retrieved from https://plants.ifas.ufl.edu/plant-directory/lonicera-japonica/

A Hoary Plant

The foliage along the trails at Fox Island tends to blend together, and for many people (like me) it’s hard to spot the differences between plants. But if you look closely, you’ll notice that there is one common plant that has a unique color pattern on the leaves: while the tops of the leaves usually have the familiar green, the undersides of the leaves have a contrasting silvery hue.

The undersides of autumn olive leaves have a silvery tint. (Photo by Nathan Arata.)

The undersides of autumn olive leaves have a silvery tint. (Photo by Nathan Arata.)

This plant is the invasive autumn olive (Elaeagnus umbellate). It was introduced from Asia to North America almost two hundred years ago. The origin of the plant, when combined with that silvery hue of both the leaves and the unripened berries, explains why autumn olive is also commonly known as Japanese silverberry.

How will you know if you are looking at autumn olive? First look for the silvery undersides of the leaves. In late spring, autumn olive produces clustered white flowers that are favored by many of the pollinators at Fox Island. The fruits, which turn from silver to red when they ripen, are an important food source for many animals at Fox Island. The popularity of the flowers and seeds means autumn olive can be found almost anywhere.

Autumn olive is a major food sources for many animals and provides shelter for many others. It also houses nitrogen-fixing bacteria in its roots, which allows it to grow in soil that many native plants cannot grow in. Combine all of these factors together, and it’s not hard to see why autumn olive has become so widespread.

A wall of autumn olive grows along the edge of the forest, near the prairie and the swamp white oak. (Photo by Nathan Arata.)

A wall of autumn olive grows along the edge of the forest, near the prairie and the swamp white oak. (Photo by Nathan Arata.)

Autumn olive grows thick. It was originally planted in many areas to create natural hedge barriers. Unfortunately it’s really good at this, and in many Indiana ecosystems, it grows so densely that it hinders native plant growth.

In Indiana and in other parts of North America, autumn olive has been classified as a noxious weed. It’s very hard to remove. If the plant is small enough you might be able to pull it, and this may be enough, provided you get the entire plant (including the roots). But if it is big enough, then like many of the invasive plant species at Fox Island, simply cutting autumn olive down isn’t enough to eradicate it. The roots need to be chemically treated to ensure the plant cannot grow back.

You are most likely to see autumn olive at Fox Island along trails, roads, and at forest edges. You are especially likely to find it at the edges of both the east and west prairie habitats and along the lake road. Have you seen autumn olive in Fox Island? Comment below and let us know when and where you saw it. And contact the park staff to see how you can get involved in removing it!

References

Nature Conservancy. (2019). Journey with Nature: Autumn Olive. Retrieved from https://www.nature.org/en-us/about-us/where-we-work/united-states/indiana/stories-in-indiana/autumn-olive/

Ormiston, J. (2019, April). Personal interview.

Penn State Extension. (2019). Autumn Olive. Retrieved from http://extension.psu.edu/autumn-olive

Weston Nurseries. (2013). Autumn Olive – A Challenging Species. Retrieved from http://www.westonnurseries.com/autumn-olive-a-challenging-species/

An Ornate Invader

Fox Island’s trails can get muddy, and the park itself holds a lot of water. Visit the park in the spring, or visit after a day or two of heavy rain, and you’ll see what I mean. This isn’t a total surprise. The park is adjacent to the 700-acre Eagle Marsh. And within Fox Island itself you can find seasonal ponds, wetland forest, a large marsh, and of course Bowman Lake.

The flowers of Purple Loosestrife. (PHoto by Ivar Leidus via Wikimedia Commons.)

The flowers of Purple Loosestrife. (PHoto by Ivar Leidus via Wikimedia Commons.)

As you are walking around Fox Island’s wetlands, you may notice some plants with pretty purple flowers. Bad news: those plants probably aren’t supposed to be there. There is a good chance you are looking at invasive purple loosestrife (Lythrum salicaria).

It’s no accident that those purple flowers are pretty. Purple loosestrife was brought to the United States from Europe over 150 years ago. It’s not clear if the species was introduced intentionally (as a garden plant) or unintentionally (as seeds carried in cargo ship ballast). But it is clear that the plants become very popular due to those purple flowers.

Soon after it was introduced, it was sold and cultivated throughout the eastern United States as an ornamental plant. The seeds it produces are small and easily spread by wind, water, and animals. And it produces a lot of seeds—one plant can produce millions in a year.

Unfortunately purple loosestrife has had a pretty devastating effect on wetlands in Indiana and elsewhere. The plants grow so densely that that crowd out other (native) plants. And the plants also cause problems for animals. Purple loosestrife takes away habitats and space for many animals and it crowds out the food sources for other animals.

How will you know if you’re looking at purple loosestrife? If you’re near a wetland, you’ll see tall, purple flowers—they can be several inches tall, in fact. The plant itself can be up to six feet tall. Remember, they grow densely, and you probably won’t see just one purple loosestrife plant growing by itself.

Purple loosestrife isn’t a big problem at Fox Island compared to some other invasive plants. But it’s a big problem in other areas close by. And there is always the potential for it to become a bigger problem at Fox Island.

Have you seen purple loosestrife in Fox Island? Comment below and let us know when and where you saw it. And contact the park staff to see how you can get involved in removing it!

 
The pond behind the nature center is a potential home for Purple Loosestrife. (Photo by NathAN Arata.)

The pond behind the nature center is a potential home for Purple Loosestrife. (Photo by NathAN Arata.)

 

References

Indiana Department of Natural Resources. (2019). Purple Loosestrife. Retrieved from https://www.in.gov/dnr/entomolo/4529.htm

Minnesota Department of Natural Resources. (2019). Purple Loosestrife. Retrieved from https://www.dnr.state.mn.us/invasives/aquaticplants/purpleloosestrife/index.html

Ormiston, J. (2019, April). Personal interview.

University of Minnesota. (2017). Purple Loosestrife: What you should know, what you can do. Retrieved from http://www.seagrant.umn.edu/ais/purpleloosestrife_info