Nature Blog

Ripples 6/22/17

 Written by Julia Adams, summer education intern

Summer is a great time to see many beautiful, colorful plants and flowers beginning to grow. It’s always  refreshing to see the bright colors after the dreary winter passes. Seeing the bright purple color of the flowers on the dame’s rocket plants lately, was a great reminder that spring and summer were finally here. Little did I know, dame’s rocket is an invasive species that I would soon help to remove from the Woodland Dunes Nature Preserve.

photo of dames rocket

dame’s rocket

The first day I was removing dame’s rocket with some fellow interns, I saw only a few and thought that there was not much of a problem, or, the other workers and volunteers from the preserve were very good at removing it. After picking for a little while, I noticed through some trees where there were more. As I walked closer, the area was not as small as I had originally thought. There were spots in the preserve that were almost completely covered in dame’s rocket. That’s when I knew this was an important problem to solve.

Invasive species are non-native that can harm the environment. Dame’s rocket grows very rapidly and grows tall enough to block the sun from getting to native species. Because of this, the native species can’t get enough sunlight and eventually end up being overtaken by the dame’s rocket. Since these species are native, it is important to keep them in the preserve to help native wildlife that may use these plants. Dame’s rocket makes this more difficult to achieve.

Dame’s rocket is very easy to identify. It is part of the mustard family and came to the U.S. in the 1600s. It was planted and used as an ornamental species. However, because of it’s high seed production, it quickly escaped cultivation and grew in the wild. Dame’s rocket thrives in areas such as prairies, roadsides, ditches, open woodlands, and other disturbed areas. The plant can grow up to four feet tall and has leaves that alternate – going up and down the fuzzy, rough stem. At the top of the plant there are flowers that have four petals that make a cross. The flowers can be purple, pink, and white and usually bloom in the late spring. The first year of growth tends to be just foliage, and in the second year, the flowers start to bloom.

When you encounter dame’s rocket, it can commonly be confused with phlox, which also has purple flowers but has five petals instead of four. Once properly identified, dame’s rocket can easily be removed by pulling out the root by hand, if the soil is soft, or by digging the root out with a small spade. Because it is an invasive species, dame’s rocket is not to be purchased or planted in Wisconsin. Although the flowers are beautiful and the colors are pretty, this invasive species can harm the environment and ecosystems around us and should be removed when possible.

Ripples 6/15/17

-written by Jessica Johnsrud, Education Coordinator at Woodland Dunes

At least once every June, an event occurs that tells me summer is right around the corner. This event would happen even when I was a young girl. It happens when I am outside close to dusk enjoying a campfire or walking my dog. Suddenly, bam! A june bug will crash into my head and get caught in my wavy hair. I can hear the insect’s buzzing as it dislodges its hairy legs from my hair and flies away. These bugs, which are actually beetles, also bombard the windows at night because they are attracted to the light within house. For me, the arrival of these clumsy insects marks the beginning of summer.

photo of male ovenbird singing

Male Ovenbird Singing

There are other sounds associated with the onset of summer. A few hearty songbirds will sing through the day, until dusk. American Robins sing their bright “cheerily, cheer-up!” song and the Gray Catbird combines a series of odd sounds, imitations and even sings a raspy “mew!” that sounds like a cat’s meow. Common nighthawks make an appearance at dusk. They gracefully swoop through the sky, eating insects and periodically make a sharp, “peent!” call.

Though they are silent, fireflies are another sign that summer is almost here. These enchanting insects create light through a chemical reaction inside the lamp organ, which is located on the last few segments of their abdomen. The male fireflies flash as they patrol the air to advertise to the females, who wait on the ground or perched on a plant or shrub. If a female is interested, she will respond by flashing back. About ten years ago on a late May evening, I walked among so many fireflies that the trees and understory plants in the forest around me looked as though there were decorated with holiday lights! It was truly a magical sight that I will never forget.

American toads and gray tree frogs can also be heard singing away during the day and in the evening. Their voices carry quite a distance because of the use of vocal sacs. When singing, they close their mouth and nostrils and push air from the lungs through the larynx and into the vocal sacs. The vibrations of the larynx make a sound that is amplified by the sac and hopefully attracts the attention of females in the area.

Many sounds of early summer can also be heard during the day. There is a chorus of bird songs in the preserve that is best enjoyed in the early mornings or later in the afternoon. Ovenbirds frantically chant, “Teacher! Teacher! Teacher! Teacher!” The red-eyed vireos lazily sing, “Here I am. Up here. In the tree. At the top. Vireo.” Bumble bees buzz as they collect pollen from the various plants that are in bloom. The crickets have also started to call. They stridulate, or produce a chirping sound through friction. They rub a “scrape” at the base of one of the forewings against a “file” located on the base of the other, like a thumbnail on a comb.

Spending time outdoors in the late spring is truly a multi-sensory experience!

photo of Ovenbird by Nancy Nabak

Ripples 6/8/17

Ripples from the Dunes, written by Mikayla Opichka and Anna Hall, summer interns at Woodland Dunes

Over the past few decades, much anxiety has been associated with the term “mussel” in the Great Lakes region. Many of us connect it with the invasive zebra mussels, which have been invading our water ecosystems and changing the lake environment drastically. However, not all mussels in the Great Lakes region are invasive. On the contrary, they are an essential aspect of a healthy aquatic landscape. They serve many purposes including, but not limited to, filtering water, being a food source for many animals, excreting readily used nutrients into the ecosystem, and provide an aquatic substrate for algae and insect larvae to attach to.

photo of people searching for freshwater mussels in the river

Searching for freshwater mussels

Last week, Woodland Dunes was very fortunate to have a mussel expert from the Department of Natural Resources(DNR) present information pertaining to the mussels of our region, and then followed up by guiding participants on a mussel survey of the East Twin River in Mishicot. The DNR has begun the Mussel Monitoring Program of Wisconsin, which has been studying all 51 native species of mussels in the area. All of these species have distinct environment preferences. Some of the species within Wisconsin include the Spike, Plain Pocketbook, Threeridge, Monkeyface, and the Creeper.

The mussel’s complex life cycle fascinated participants. The female mussel sits downstream waiting to catch its male counterpart’s gametes. The female must transfer the juvenile mussels to a host fish, where they will mature in the fish’s gills. She then uses an appendage called a lure that realistically imitates a small fish that bait larger fish. Once the host fish takes the bait, the sac explodes, bringing the juvenile mussels in contact with their host. When they are mature, they leave the host fish and begin their own adult mussel life within the substrate of the aquatic ecosystem. This process is an incredible example of evolution that has helped further the lives of successful mussels!

Everyone left with a new passion for freshwater mussels and the knowledge that these mussels are in our own backyards. The Wisconsin DNR is looking for volunteers who are interested in exploring the mussels of our region. Anyone can easily participate in this effort by stepping into the nearest body of water and searching for these freshwater critters. (It is helpful to have an aquascope to help view the underwater substrate, but if you do not have an aquascope, don’t fret! One can easily be created using household materials such as a milk jug, saran wrap, and rubber bands, or by using PVC pipe and plexiglass.) Once you have located a mussel, all you need to do is upload an image of the creature to the wildlife-centered social media platform called iNaturalist, which can be found on the web at and also on the App Store. This wonderful site will help identify the mussels as well as keep track of what species are located in each body of water.

photo of people on riverbank identifying freshwater mussels

Identifying freshwater mussels

A day spent outdoors is never wasted, and we encourage you to take some time to encounter these underwater wonders!

photos- Woodland Dunes staff and volunteers looking for freshwater mussels with Jesse Weinzinger of the Wisconsin DNR  in the East Twin River, Mishicot; six different species of mussels found during program.

Ripples 6/1/17

Suddenly it’s summer.  The spring migration is coming to an end, and the nesting season is well under way.  Early spring wildflowers have bloomed, but mid-season plants are ready to vie for our attention. Plants in general seem to be putting on remarkable growth- especially in lawns it seems!

In the preserve, the nodding trilliums are now blooming, although much more demure than their grand cousins of drier, warmer woodlots.  Violets, starflower, bunchberry, blue-bead lily, and Canada mayflower are blooming at the Dunes and Point Beach, similarly as in the far north woods.  In the meadows, many of the native prairie plants are still just waking up (they don’t call them warm season species for nothing).  On sandy fields, common milkweeds are bolting upward, as if to welcome the monarch butterflies migrating from the south, females eager to deposit the next generation’s eggs.  Monarchs were seen very early this year, weeks ago already, apparently borne northward on strong south winds.  This is good, they will have ample time to build their population before the fall migration, which will occur all too soon.

photo of wood violet

wood violet

All this – birds, wildflowers, and spring plant growth are so positive that it’s difficult to face the realities of land management.  Our staff and volunteers know all too well that in the midst of the sea of green, exist plants that don’t belong. Plants that threaten to change the face and function of our forests, marshes, and fields, and have done so already.  In the fall, winter, and spring seasons we work to remove invasive shrubs.  In late spring, the shrub treatments become less effective so we switch to replanting formerly invaded areas and removing alien wildflowers that would crush our natives.

The beautiful purple and white flowers of dame’s rocket, a native of Eurasia, is an obvious target as the plant suddenly erupts into bloom. We pull out as many as we can and have had success in clearing some areas, but it is a very hardy plant with few natural enemies. Pull we must, encouraged by every native wildflower and fern we uncover.

We couldn’t do all of this without our wonderful volunteers, and one of the most helpful is Don DeBruyn of Two Rivers.  He spends many hours helping us in our never-ending land management battles and is truly a blessing, not only to Woodland Dunes, but to the community in general.  Last week, while helping to pull dame’s rocket along Columbus St., he did something that I have been dreading for many years- he discovered the first patch of garlic mustard in our preserve.  By now, many of us are familiar with garlic mustard, an invasive plant that was unknown here 30 years ago.  Now it seems that it is found in more places than not, and is especially threatening because it will grow well in shade and readily invades woodlands.  It crowds out native plants, injects chemicals into the soil that disrupt native fungi (on which plants depend), and prevents tree seedlings from growing.  Last year, our staff found a small patch across the street and it’s likely that deer or raccoons transported the tiny seeds to our woods.

photo of garlic mustard

garlic mustard

Don immediately pulled any flowering mustard plants to prevent them seeding, but there are hundreds of young plants among the wood violets, oak ferns, and other wildflowers in a small area.  We recorded the location with a GPS unit and will monitor weekly for any more flowers this year.  After the wildflowers die back later on, we’ll look at removing those young plants before they get a chance to flower next year. We’ll also check along other animal trails in the area. We’ll also need to take precautions so that we don’t spread the seeds ourselves.

There will be no easy fix for this.  Wildlife moves around, as it should, and there can be consequences that we don’t like as a result. We can’t build a wall to keep these aliens out- we have to deal with problems that arise thoughtfully and rationally.  Perhaps in doing so we’ll discover new ways to keep our forest healthy and preserve the diversity of its makeup.  We know that doing so will always be a challenge, and although it won’t be easy, we should never stop trying.

Photos-  native wood violet and young garlic mustard plant, similar in appearance.

Ripples 5/26/17

I had never heard the secrets of the West Twin river until I kayaked it Monday, May 23rd. Sumner Matteson, an avian ecologist from the Wisconsin DNR, and I kayaked the West Twin as part of the Great Wisconsin Birdathon (a fundraiser for the Natural Resources Foundation), and to create awareness around the developing canoe/kayak trail between the West and East Twin Rivers.

As I said, I’d never heard the secrets of the West Twin before, and I don’t think anyone fully has unless they’ve experience the river first-hand. But if you pay attention, she will share.

Matteson and I launched at 6:45 am (temperature – 49 degrees and a westerly wind of 18 miles per hour), but we dressed for the weather and paddled with anticipation for what was in store. Our trip began at the Shoto boat launch and ended at Vets Park, our goal – to find at least 40 different bird species by river.

My boss, Jim Knickelbine, wisely advised me to go upstream a bit and then head back down. He was right on the money. As we paddled north, we came upon a shrubby little cove that was filled with singing and buzzing migrating warblers. Wilson’s, Canada, Blue-winged, Chestnut-sided and more were flitting and bouncing on branches as we sat with binoculars focused. We also heard the beautiful upward-spiraling, flutelike song of the Swainson’s thrush. True to its nature, it stayed out of sight, but it was nice listening to the “flute” as we watched other birds move about.

Prior to reaching the cove, we spotted a dark mink galloping alongside the riverbank. I’m not sure what it was in search of or where it was going, but the sight of the bounding critter was a treat as we witnessed nature waking up on the waterfront. The West would end up revealing two minks that day.

On the International Scale of River Difficulty, the West is slower than a “class 1 – easy” river. So if extreme kayaking is your thing, give this scenic, meandering river a try just for a switch-up. There are no rapids, no obstructions or difficult maneuverings that need to be made. She’s built for a smooth ride.

We criss-crossed our way to explore the marsh, grass cover, then forest habitats and were successful in finding Great Blue Heron, three of the four terns in Wisconsin (Common, Foresters and Caspian), spotted sandpipers, and a beautiful juvenile Bald Eagle who was nearly invisible until our kayaks were under the tree where it perched. We also discovered blue-winged teal, ruddy duck, green-winged teal, five types of sparrows and three types of wrens. And who could forget the two spotted fawns lying in the grass on the riverbank?

After five hours of kayaking on the West Twin, we had discovered 97 different bird species, well surpassing our goal. My partner feels the juvenile black-crowned night heron was the “bird of the day.” I argue that the yellow-bellied flycatcher was. But we both agree that the Eastern Meadowlark (a bird that is normally found in prairie areas), singing about a block east of Woodland Dunes in an urban area was a complete surprise, proving once again, nature is excitingly unpredictable. We also agree that the West Twin River has many more secrets to share and we can’t wait to get out there again to discover them.

Nancy Nabak
Communication & Development Coordinator