Nature Blog

Ripples 7/18/19

by Kelly Herfendal, Woodland Dunes summer education intern
photo of spittle on grass



Have you ever been walking in your garden and noticed what appears to be bubbles on your plants? It may appear as if the plants are salivating, but these bubbles do not come from the plants. They come from an insect called a spittlebug or froghopper. This bug gets its name based on the nymph stage and adult stage of its life cycle. In the Midwest, the most common spittlebug is the meadow spittlebug Philaenus spumarius, and it is frequently seen here around Woodland Dunes.

The froghopper nymph is more well-known than the adult because the nymph is what creates the bubbles on the plant. The nymph, called a spittlebug, stands head down and pierces the plant’s stem in order to suck a plethora of the plant’s juice which is the spittlebug’s food. The spittlebug then excretes the remaining plant juice as urine through its rear end and creates a frothy substance called spittle which looks like bubbles. Plant juice consists mostly of water and is not very nutritious. Therefore, a spittlebug must drink copious amounts of plant juice in order to obtain nutrients. In fact, a spittlebug excretes approximately 150-280 times its body mass in urine every day.

The spittlebug lives in this bubbly home until its instar period of development is over. The bubbles provide protection from predators such as birds, wasps, and spiders. Not only do the bubbles hide the spittlebug but the bubbles have a bitter taste which further deters predators from wanting to eat the spittlebug. A spittlebug breathes by sticking its abdomen out of the bubbles to acquire oxygen. When startled, the spittlebug hides in the bubbles and pops smaller bubbles to form one large bubble. This large bubble acts as an extra supply of oxygen so that in case of an emergency, a spittlebug can remain hidden while it still has access to oxygen.

When the nymph is ready to become an adult, it creates one big bubble to live in, just like its emergency bubble. The spittlebug continues its instar period of development in the bubble as it molts until it becomes an adult and coins the term of froghopper. The froghopper is no longer able to produce spittle to protect itself; thus, it must hop like a frog away from predators to prevent being eaten. In September or October, the female froghoppers will lay eggs on plants or in plant debris. The eggs will live there until late April or Early May when they hatch as spittlebugs and begin forming their spit cocoons.

Although many people worry that these bugs are a pest to plants, they really do no harm. Neither the spittlebugs nor the froghoppers do damage to the plants. They show up in small numbers and are only on the plants for a short time to grow into adults. So, when you are walking through your garden or a grassy area, you can stop and marvel at the bugs that live in spit.

spittle photo by Kelly Herfendal, spittle bug by Nancy Nabak

Ripples 7/11/19

As I looked out the window on a recent calm morning, I saw that the lilac bush outside was covered in delicate strands of spider silk. They waved and gleamed in the early morning sunshine, and I thought of the untold number of little spiderlings moving from one place to another before reaching adulthood. Young spiders often release a strand of silk from their abdomens which is is caught up by the wind, carrying the little beasties to new places. They call it ballooning, and it is an effective and efficient way of traveling, even at great heights.

photo of ebony jewlewing damselflydragonfly

Ebony jewelwing

As our seasons progress, we pass through times when different animals and plants are most noticeable – the time of sleeping trees in winter, the time of birds in the spring, the time of insects (and spiders) in mid-late summer, and the time of trees in the fall. Wildflowers of different species are present throughout the warm months and give us a carpet accessorized by the others.

Insects and spiders should not be the subjects of fear or disgust, overall.  For every annoying mosquito or black fly there is a pollinator helping to feed us.  For every creepy tick there is an amazing butterfly. And of course, we should take precautions to prevent diseases transmitted by certain insects/ticks and not do things that encourage spiders to bite, but these hazards have been with us as long as people and invertebrates have lived together. Even though I am often being bitten in the process, I still think that watching fireflies in mid-summer is magical. And this appears to be an exceptional year for fireflies.

A friend of Woodland Dunes called the nature center the other day to say that she missed watching dragonflies at a site where a pond was long ago filled in. The dragonflies and their relatives are truly remarkable. I am not an expert, but I appreciate the many colorful species of dragonflies, damselflies, pondhawks, meadowhawks, skimmers, clubtails – they are such a challenge to identify especially on the fly. My favorite is the ebony jewelwing, which lives around small rivers and streams. To me, they are a work of art.

As usual, birds have taken center stage so far this season when it comes to singing, but soon insects will begin to join them: cicadas, grasshoppers, crickets – they will more than fill the void when the birds go silent. Silently accompanying them are the thousands of species of butterflies and moths, in forms too numerous to mention. 

It is difficult to think how vast and complicated nature is, and how many parts (species) it takes to make it work. People oversimplify nature, and sometimes try to reduce it to what they perceive as useable.  To do so is a mistake. Like birds and other wildlife, insects are facing a slow decline in population in many places, probably due to our activities. At our preserve, we do what we can to protect native wildlife – lets hope we are more thoughtful on a larger scale as well.

photo- ebony jewelwing damselfly from wikipedia

Ripples 7/4/19


Written by Greta Wilkening, Woodland Dunes summer intern

photo of sea lamprey

Sea lamprey

Excessive sea lamprey populations have been causing problems in the Great Lakes for many decades, first appearing in Lake Erie in 1921, and continuing to invade the Great Lakes into the mid 1900s. Using their heavily-toothed mouths to attach to and feed on fish, these invasive aquatic species contribute greatly to native fish populations’ decline. That’s why the U.S. Fish and Wildlife Service conducts surveys and control projects within the Great Lakes to monitor these deadly creatures. We had the good fortune of joining two U.S. Fish and Wildlife Service employees as they went out to Forget Me Not Creek in Two Rivers to collect data for their sea lamprey survey. It had rained heavily the night before we went out electroshocking- the process used to gather sea lamprey specimen for data collection – meaning the test site’s water levels were high, and the water was fairly turbid, or cloudy. Geared up in tan waders with electrofishers, the machines used for electroshocking, secured to their backs, our trusted lamprey guides seemed to have come right out of the movie Ghostbusters.

Up to their knees in murky creek water which resembled chocolate milk, nets outstretched in front of them, the U.S. Fish and Wildlife Service workers began to electroshock. The process of electroshocking includes going along the edges of the stream, using a pulse to disturb the lampreys from their resting place in stream bed sediments, then utilizing a higher voltage shock to immobilize and capture them. This particular morning, however, with the water high and murky, the low visibility prohibited our lamprey experts from catching any of the invasive creatures for their survey. Usually, after catching sea lamprey samples from their given test site, the US Fish and Wildlife Service workers will bring them back to their truck for identification, where they have to distinguish between native and invasive lamprey species. Using the lip, dorsal fin, and pigmentation, a seasoned worker can quickly identify a native versus an invasive lamprey. For example, when looking at the lip, a window shape indicates a native lamprey, whereas a white “mustache” or “lipstick” appearance on the lip indicates an invasive sea lamprey.

Most people likely think of lampreys as purely invasive, but in fact there are four native lamprey populations within the Great Lakes area: Silver, Chestnut, American Brook, and Northern Brook lamprey. These native species are not the notoriously destructive invasive sea lamprey that first come to mind. In fact, two out of the four native species, the American Brook and Northern Brook, are not even parasitic. Only the silver and chestnut lamprey act as a parasite like the notorious sea lamprey, and even then, are not considered much of a destructive threat to native fish populations. The parasitic sea lamprey, however, is considered much more dangerous and deadly. According to the U.S. Fish and Wildlife Service, an adult sea lamprey will kill around 40 pounds of fish within its lifetime, potentially more. A fish that has been attacked by a sea lamprey only has roughly a 15% chance of survival, while a fish attacked by a native lamprey rarely ends in fatality.

Even though sea lamprey often go unseen, the threat they pose to native fish populations is very much a reality. With current and past efforts from the U.S. Fish and Wildlife Service, the Great Lakes has seen a 90% reduction in sea lamprey populations in the majority of treated sites, meaning safer and healthier waters for native fish.

photo- sea lamprey on a lake trout from Wikipedia

Ripples 6/27/19

Written by Kelly Herfendal, Woodland Dunes summer education intern
photo of monarch butterfly

Monarch butterfly

The summer solstice marks the beginning of summer and here at Woodland Dunes there is new life making its way forth now that spring is over. The House Finch and Barn Swallow chicks living in the pavilion are loud and proud as they wait for mom and dad to come back with food. The purple milkweed in our Butterfly Garden has fully bloomed and awaits the arrival of Monarch butterflies.

With spring gone and summer in full swing, the native plants of Woodland Dunes are able to make their appearance. Native plants have great importance not only to the land but also to animals and insects. For pollinators, native plants are the key to survival. Native plants, such as the purple milkweed located in the Butterfly Garden, give adult butterflies a place to sip nectar as well as a place to lay their eggs on the leaves where then the caterpillars will have food and shelter in order to grow. Bees rely on native plants for food and we as humans rely on bees to pollinate these native plants. Dames Rocket is an invasive species with bright, purple flowers. It attracts bees early in the summer because of its vibrancy and early blooms. This aggressive species of wildflower uses its color to trick bees into pollinating it. This then increases the Dames Rocket population and further depletes the native plant population.

Mortality rates of butterflies and bees are increasing. Many people are unaware of this or may be unaware of the cause of this. How can we raise awareness for these essential species? As the environmental education intern, this is a question I frequently ask myself. To start, promoting awareness of how relevant and crucial native plants are to an ecosystem should be the first step. Clearing invasive species will lessen competition for native plants and will help them to fill in the vacant spaces. Planting native species that provide food and shelter for all types of wildlife will not only enhance the look of one’s garden but also the health of it.

Native plants are critical for the land and animals as well as pollinators. They provide habitat for many species of birds, shelter for many species of mammals, and nuts, seeds, and fruit for many species of wildlife. Since native plants are adapted to their local environmental conditions, they assist in the conservation of water because they require less irrigation for development and can hold more water in their roots. Because they assist in all of these wonderful things, native plants are detrimental to our ecosystems and to our climate.

Native plants have a plethora of benefits. They contribute considerable amounts of food and varying types of habitats for many species. These species of animals and insects depend on native plants for their way of life. Without these native species, ecosystems may crumble and species may become extinct. This is why awareness and appreciation for these native plants are vital to an ecosystem and deserve our full attention.

photo- monarch butterfly by Nancy Nabak

Ripples 6/20/19

Written by Ebyn Shambeau and Isabella Scheibl, Woodland Dunes summer interns

photo of giant hogweed

giant hogweed

Summer is right around the corner which means we are starting to see some familiar plants!  You may notice some new large plants on the edge of your property, along waterways, or on the tree line of your local woodland. Although new plants are exciting to find, there is a dangerous invasive species close to our area.  Heracleum Mantegazzianum is a plant that you have probably heard about in the recent past. Known more commonly as Giant Hogweed, this is a harmful nonnative that grows in moist soil anywhere it can. Due to this year’s immensely wet spring/early summer, Giant Hogweed will most likely continue to thrive in the six Wisconsin counties where its presence has already been confirmed.

Giant Hogweed is a very robust, stalky plant. The plant can grow an average of eight to twenty feet which easily crowds out all surrounding native plant species. The flowers of this plant are mainly white with large umbels. Hogweed is commonly misidentified as American Cow Parsnip, but unlike Giant Hogweed which is native to Asia, American Cow Parsnip is native to Wisconsin.

You may be wondering “How do I tell the two plants apart if they look so similar?” Luckily, we have two easy ways to tell the difference. First, Giant Hogweed is the larger of the two growing up to twenty feet tall. American Cow Parsnip only grows three to seven feet tall. Secondly, upon closer observation, Giant Hogweed has a single leaf structure with lobes that look like a hand with finger, while American Cow Parsnip has leaves similar to the shape of Maple tree leaves.

Not only is Giant Hogweed harmful to native plants, but it’s also hazardous for humans as well. When getting rid of Hogweed it is highly suggested that clothing cover all skin and protective wear for your eyes and face is utilized. Giant Hogweed possesses sap that is released when the plant is cut or damaged. If this sap gets on your skin, it will undergo a process called phytophotodermatitis. If the affected skin comes into contact with sunlight it can cause burns, rashes, blisters, and discoloration that can last several years. To combat the damage that the sap can cause, quickly wash the affected area with cold water and keep the area cool, dry, and out of sunlight. To combat the spread of the plant itself, there are two options. The first of which would be manual removal using a shovel to dig one to two inches below the plant to remove it from the ground. The entire plant can then be burned or bagged for landfill disposal. The second way is the chemical route which involves the use of a foliar spray or cut-stump method followed by treatment of herbicide.

Giant Hogweed is an invasive which is harmful to everything that it comes in contact with, whether it be humans, animals, or native plant species. Even though Giant Hogweed was originally brought to America as an ornamental plant, there’s nothing pretty about it.

photo- Giant Hogweed by Fritz Geller-Grimm