Keystone Natives for the Food Web

Last week during my Native Plant School class, I had an interesting question posed to me and it made me pause to think.  The question was “Do you have a list of keystone native perennials for a healthy food web?”  The person obviously had been reading Doug Tallamy’s book, Nature’s Best Hope: A New Approach to Conservation that Starts in Your Yard.

The food web includes, plants, insects, pollinators, birds, lizards, toads, frogs, and mammals, from rodents up through bears.  Each is reliant on the other for their survival. Tallamy focuses much attention on trees that support the food web such as oaks, cherry, cottonwood, willow, and birch.  However, there are many native perennials that are also key components of this food web. To provide a solid foundation for a healthy food web in your garden, start with this list of native wildflowers to include in your landscape:

Goldenrods (Solidago sp.)

These summer blooming wildflowers with bright yellow flowers can be striking in the landscape. However, they have a reputation for causing allergies. In truth, this is unlikely because goldenrod pollen is large and heavy and is not carried by the wind. Rather, it is giant ragweed that is spreading pollen through the air at the same time. The plant is insect-pollinated by many wasps, moths, beetles, honey bees, monarch butterflies and other beneficial pollinators searching for a sip of nectar.  In total, 11 specialist bees and 115 different caterpillars need these plants. There are around 50 species of insects with immature forms that feed on the stems of goldenrod.

I like Solidago rigida, Solidago nemoralis, Solidago ‘Wichita Mountains’, Solidago canadensis ‘Golden Baby’, and Solidago ‘Fireworks’ for sunny areas. For shade, I choose to plant Solidago odora, Solidago ulmifolius or Solidago caesia.  It is safe to say that goldenrods are powerhouse plants that deserve a place in your native garden.

Rigid Goldenrod with red switchgrass

Asters

A diverse genus that supports 112 species of insects, asters are a valuable late-season (September – November) source of pollen for bees and nectar for bees and butterflies. During the summer, the asters are host plants to the caterpillars of some of the crescent and checkerspot butterflies. As summer wanes, asters start blooming with colors of white, purple, and pink depending on the species.  Fall provides a unique challenge for pollinators and asters help with both migration and overwintering butterflies and bees. 

A few of my recommended forms are Aster oblongifolius ‘Raydon’s Favorite’ and ‘October Skies’, Aster novae-angliae varieties, Aster laevis and Aster ericoides ‘Snow Flurry’ for sun.  In a shady area, try Aster divaricatus ‘Eastern Star’, Aster cordifolius, and Aster macrophyllus.

Aster ‘Raydon’s Favorite’

Sunflowers (Helianthus sp.)

There are eleven species of sunflower recorded in Kansas. These wildflowers are not usually fit for a formal garden setting, because they spread vigorously by seeding and rhizomes.  They have a tendency to push out other desirable plants.  However, they support 73 species of insects, so we maybe need to find a place for them. 

I’m not referring to the large-headed annual cultivars you see growing in a field, but rather the true native perennials with bright yellow flowers seen growing along the roadside in the late summer and early fall.  Plants provide lots of nectar and pollen, and the seeds are eaten by many birds and other wildlife. I would encourage you to try a few sunflowers in the peripheral areas of your yard where they can spread out and have room to roam. 

Maximillian Sunflower and Big Bluestem

Milkweeds

Monarchs are in peril. Milkweeds are one of the answers to reversing their plight. By planting more milkweeds, monarch will find these larval food sources more readily. Milkweeds are larval host plants for Monarch and Queen Butterflies and the Milkweed Tussock Moth. Many bees, wasps, butterflies and beetles visit milkweed flowers for the nectar. Milkweed plants typically produce a lot of nectar that it is replenished overnight. Nocturnal moths feast at night and other pollinators flock to these important plants during the day. 

Choose butterfly milkweed (Asclepias tuberosa) or green antelope horn milkweed for your formal garden and common, Sullivant’s, or whorled milkweeds for the outskirts of your property. 

Newly hatched monarch caterpillar on common milkweed.

Blazing Stars (Liatris sp.)

Liatris are very important wildflowers. The vibrant purple blooms in summer support many great insect species. They are quite adaptive with different species growing in dry to moist soil conditions. There is literally a blazing star for just about every garden setting. 

I prefer Liatris pycnostachya and Liatris aspera, but many others, including Liatris ligulistylis and Liatris punctata, are nice too.    

Liatris pycnostachya

There is a growing body of research that touts the benefits of keystone species of trees, shrubs, wildflowers and grasses to the food web. According to Doug Tallamy, landscapes without keystone plants will support 70–75% fewer caterpillar species than a landscape with keystone plants, even though it may contain 95% of the native plant genera in the area.

Planting just natives is not enough. Garden designs and plant communities must contain at least some keystone plants to positively impact the food web. This is the start of a list, but there are certainly more plants to choose from.  Look for more suggestions in the coming weeks. 

Bagworms: Pest Spotlight

Bagworms have done tremendous damage this year.  Here at the Arboretum, we made multiple applications to our junipers and spruce to get them under control.  Thankfully, we have not had to manage bagworms the past five years too much. However, across the countryside this year, juniper shelter belts are covered with thousands of brown bags dangling from the branches.  These are not very festive and don’t bode well for 2021.  

Bagworm Life Cycle

Here is a glimpse into the various bagworm life cycle stages throughout the year:

In late May through early June, the eggs deposited in the bags the previous fall begin to hatch. Once the eggs hatch, the larva spins a silk strand that hangs down. These larva begin eating immediately or wind transports them to nearby plants.

Once the larva finds a host, it starts to make a new protective bag around itself. It remains inside this bag, sticking only its head out to eat from the host. If large populations exist on the same plant, they can do tremendous damage as they continue to mature.    

The larva continues feeding until it matures by the end of August. It then attaches the bag they are in to a branch with a strand of silk and starts developing into a pupa.

Adult male worms appear in September. These are tiny, grayish, moth-like insects with fur on their body and transparent wings. Adult bagworm females are wingless. They never leave the protective bag.

Mature male and female worms mate with each other to produce offspring. Strikingly, these pests die after mating. Male moths die outside the bag while females die inside the bag and get mummified around the mass of up to 1000 eggs in her case.  The eggs hatch in end-May or beginning of June the following year. 

Only one generation of bagworm eggs are produced every year.

Bagworm Hosts

Bagworms feed on a wide variety of trees and shrubs, but is primarily a pest on evergreens such as arborvitae and Eastern red cedar, cypress, and spruce. Bagworms are quite adaptive. In the absence of these preferred hosts, bagworm will eat the foliage of just about any tree: fir, pine, hemlock, sweetgum, sycamore, honey locust, black locust, willow. Adult moths do not feed, living just long enough to mate. I have even seen them hanging off brick foundations, signs, and houses.  They use the paint flecks to camouflage themselves.

Natural Controls

Each year, bagworm populations vary widely.  Parasitic wasps, diseases, low winter temperatures, bird predation affect population size.  Sometimes large populations are shortlived and let’s hope that is the case this year.  With large populations existing this year, we are set for another bagworm problem in 2021 if some of these other controls don’t happen.

Manual Controls 

Because bagworms are so conspicuous, overwintering bags and the eggs they contain can be picked from small trees and shrubs now and then destroyed. This is a viable option on small areas and smaller trees.  You must discard, the bags completely because any surviving eggs will hatch and disperse larvae to re-infest trees.

Spraying for Bagworms

It is critical that you monitor your trees in June for bagworms.  The most effective time to control them with spraying is when the bags are less than ¼ inch in length. We use DiPel® DF biological insecticide dry flowable on the bagworms. This proven insecticide is derived from a soil bacterium that selectively targets destructive caterpillars and worms. This product is highly selective and will not harm beneficial insects. It contains Bacillus thuringiensis (Bt) that the larvae ingest, giving them a terminal stomach ache. It usually requires several applications with a high pressure sprayer to get the spray to the tops of the tree but it is very effective and safe. 

The biological control we have been using to control bagworms

There are other labeled, registered insecticides available to use as an alternative means of control against small bagworm larvae in spring or early summer. These are usually not the best option because these chemicals not only kill the bagworms but other beneficial insects. We encourage you to use these as a last resort.  When larvae are more than 1/2 inch (13 mm) long, it is nearly impossible to kill them using insecticide. It is often at this time or later when bagworm infestations and associated defoliation become apparent and it is too late.

With everything else going on this year, why wouldn’t we have a bagworm problem?  It seems rather fitting.  Hopefully, this information will help you plan for 2021 to keep bagworms in check.

Predator Profile: Praying Mantis

The Carolina mantid (Courtesy of Hebard and the Illinois Natural History Survey) from An Introduction to the Study of Insects

The praying mantis is a medieval-looking predator of the garden that could just as well be a source of a horror film. Females are known to bite the head of their male partner during copulation to prevent his premature flight and then proceed to eat him after his job is done. If newly-hatched nymphs don’t find enough insects to eat shortly after leaving the nest, they start cannibalizing their own siblings. After watching my grasshopper-eating video at the end of this post, even some meat-eaters may swear off KFC for a very, long, time.

Carolina mantid cleaning its legs (video by Henry Friesen Guhr)

Identification

Praying mantises or mantids have compound eyes in freely moving heads on a pronounced neck and are the only insect that can “look over their shoulder.” Their front legs are muscular viselike appendages with spines held in front of them. They lie in wait, ambush their prey, and then hold and eat them alive.

Chinese mantid with a grasshopper

Kansas has five different species of mantids. There are three native species and two introduced. Of our native species, two are small, uncommon, typically found in prairies, and described in Insects in Kansas (Salsbury and White) as follows:

Descriptions of our two Kansas prairie mantids

For the remaining more common three species in Kansas (Carolina mantis, Chinese mantis, and European mantis), the following is a description of each provided courtesy of Missouri Department of Conservation (mantids) with bugguide.net links to photos of each individual species:

  • Carolina mantis (Stagomantis carolina). Native.
    • Pale green to tan or mottled gray
    • Adult length 2–2¼ inches
    • The combined length of the head and thorax is about as long as the abdomen.
    • The middle pair of legs are about twice as long as the antennae.
    • Females are essentially flightless, as their wings are relatively small — when folded, they do not extend as far as the abdomen tip; usually only about three-fourths of the way down the body.
    • Males may have the wings extend beyond the abdomen tip and may fly to lights at night.
    • There is a black patch on the outer pair of wings.
    • Examine the facial shield (the part of the face in front of the antennae and between the eyes: in this and other Stagomantis species, it is long and narrow (in the Chinese mantis, it is fairly square and has vertical stripes).
    • Egg cases are somewhat flattened, elongated, teardrop-shaped structures.
  • Chinese mantis (Tenodera sinensis). Nonnative. Very commonly encountered.
    • Tan to pale green; tan individuals often show a stripe of pale green on the side (it’s the borders of the green front wings)
    • Adult length 2¼–4 inches or more
    • Examine the facial shield (the part of the face in front of the antennae and between the eyes): in the Chinese mantis, it is fairly square and has vertical stripes (in our native Carolina mantis, it is long and narrow and lacks stripes).
    • Flies well, often attracted to lights at night.
    • Egg cases resemble tan toasted marshmallows. They are fairly round, about as long as wide, Ping-Pong-ball size; usually attached to twigs of bushes and small trees.
    • Native to east Asia. Introduced to North America accidentally in 1896. Later, imported on purpose in hopes of combatting insect pests. Among the many insects it consumes are our smaller native mantids, and it may be playing a role, in some regions, in the declining populations of the Carolina mantis. Because the Chinese mantis has been widespread in our country for so long, it is difficult to determine what its ecological impact has been on native ecosystems. Because of the females’ large size, they have occasionally been recorded eating small vertebrates, including small reptiles and amphibians and even hummingbirds, but these seem to be relatively rare occurrences that do not have a significant impact on populations of those species.
  • European mantis or praying mantis (Mantis religiosa). Nonnative; probably the least encountered of these three.
    • Yellowish green, cream-colored, or tan.
    • Adult length 2–3 inches
    • Diagnostic feature is a round black dot on the underside of the basal joint (coxa) of the forelegs. Sometimes this black dot has a white center. This spot can be hard to see when their “arms” are held together.
    • Egg cases are rather egg-shaped, distinctly layered structures.
    • Native to Europe. Introduced to North America accidentally in 1899. Later, imported on purpose in hopes of combatting insect pests. People may still introduce them occasionally.

For a visual comparison of the ootheca for these three species, HERE is an article with photos.

Reproduction

Once the female has been fertilized and consumes the male as a “last supper” of sorts, she develops and deposits her eggs to complete the life cycle before dying herself.

Mating Carolina mantids – completion of a life cycle before the carnage

The female mixes the eggs with a frothy, protein-based material called spumaline and extrudes them onto a stem or building. This mass hardens to form a strong Styrofoam-like casing or ootheca that helps keep up to 200 eggs from drying out over the winter.

Chinese mantis “toasted marshmallow” egg casing on a goldenrod stem

The nymphs that emerge from the ootheca in spring do not have different-looking larval stages like many other insects. They resemble adult forms throughout their entire juvenile development.

Mantid nymph (dime-sized) found during an insect sweeping activity

Biological Control

It would seem just as appropriate to name this creature the “preying” mantis. I have seen many instances of mantids munching on moths, butterflies, bees and more and recently captured video of a Chinese mantis eating a grasshopper (see end of blog).

Mantids are touted as biological control agents to get rid of pest insects in gardens and greenhouses. However, the effectiveness of this approach is questionable. While they efficiently prey on insects, a small release of mantids cannot possibly control all the insects that humans consider to be crop pests. Complicating their effectiveness, mantids also indiscriminately consume insects that we consider to be beneficial pollinators as well. And since nonnative mantid species are those most commonly distributed for biological control, some rightfully worry about the impact their continued introductions may have on smaller native mantid populations.

However you find and observe mantids in gardens and natural areas around you, observe and enjoy the habits of these fascinating creatures.

Chinese mantis eating a grasshopper at Dyck Arboretum

Monarch Fallout and A Predator Story

Monarch Fallout

It happened again in 2020. The convergence of the peak of the September monarch southerly migration over Southcentral Kansas was met by a strong south wind, causing a “fallout” of monarchs at the Dyck Arboretum. Rather than waste energy fighting the headwind, monarchs find a place of refuge to rest and sip nectar. I would estimate that I’ve seen this phenomenon happen five times in the Arb since 2005 and this year’s was the most memorable for a few different reasons including big numbers, fallout location, and a predator story.

Monarchs in the Hedge Row at Dyck Arboretum, 9/20/2020 – Photo by Gerry Epp

Big Numbers

The monarch numbers I observed on Monday, 9/21/2020 seemed to me to be more stunning than I can ever remember. I estimated conservatively in a report to Journey North, there were at least 500 monarchs resting in the Arboretum that day. But after giving it more consideration and talking to a local monarch tagger, Karen Fulk, I wonder if that number was more accurately in the thousands.

Karen’s many years of efforts to tag monarchs in Hesston has her keenly in touch with monarch phenology and migration patterns. She reports that the peak of migration through south central Kansas is usually between 9/22 and 9/27. This year, however, she started seeing an uptick in numbers when a cold front and north wind jump-started the southerly monarch migration a bit earlier.

Karen usually tags 300 annually during the fall migration. This year, Chip Taylor at Monarch Watch, knowing that migration numbers were higher this year, suggested that taggers order extra tags. Karen increased her number to 500 tags and was able to apply most of those when the fallout began Friday 9/18/2020 through Sunday 9/20/2020. Arboretum member, Gerry Epp, further documented this event by posting photos of the fallout on his Facebook page, 9/20/2020.

Monarchs on Seven Son Flower at Dyck Arboretum, 9/20/2020 – Photo by Gerry Epp

Fallout Location

With some repetition now in seeing these fallouts occur in the same place, I want to give some thought to why they congregate where they do at Dyck Arboretum. Karen usually tags at three places in Hesston based on the ability to catch and tag the maximum number in one place, and Dyck Arboretum is where she does the majority of her work. She estimated that 95% of her tagging this year happened at the Arboretum, based on seeing the greatest number of butterflies here.

I would hypothesize that they repeatedly congregate in the small 1/8th-acre area at the Arboretum amphitheater/pinetum for three reasons. One, they are seeking protection from the elements of wind and heat. This is about energy conservation. By escaping the wind and congregating in large groups on the north side of the dense hedge row of Osage orange trees, they are finding a microclimate that is cooler, more humid, and less turbulent than they would find on the south side.

Monarchs on Seven Son Flower at Dyck Arboretum, 9/20/2020 – Photo by Gerry Epp

Two, this location is next to a number of nectar sources. Why not rest where you can eat/drink too? Nearby native plant beds and a reconstructed prairie had a timely profusion of flowering from many species of the genera Helianthus (sunflower), Solidago (goldenrod), Symphotrichium (aster), Liatris (gayfeather), Eryngium (eryngo), and Heptacodium (seven son flower).

Three, a number of white pines in this location may resemble the trees of the Oyamel fir forests in Mexico. I don’t have any proof of this theory, but it seems plausible to me.

Predator Story

The newest wrinkle of this monarch fallout experience was the side story of five immature Mississippi kites. They were probably migrating with the monarchs and decided also to not fight the strong south wind. For a day and a half that I observed, this hungry bunch of pentomic predators took advantage of an abundant food supply. They hung out in the top of one of the white pines and took turns swooping through the monarch clouds to easily catch a snack.

Mississippi Kite Eating A Monarch at Dyck Arboretum, 9/22/2020 – Photo by Janelle Flory Schrock

Sometimes they missed catching their target, but usually, these agile insect catchers snagged their prey. Typically they would return to their perch to eat their catch, but sometimes they would eat in flight or “on the wing” as I hear experienced birders say. At one point, I counted approximately 120 monarch wings that had fluttered down to form what I’ll call a monarch confetti debris field. At four wings per monarch, that represented the carnage of about 30 monarchs. However, a number of wings had already been collected by onlookers, so it is not unreasonable to think that the number of monarchs preyed upon were double or triple what I saw.

Monarch Wings at Dyck Arboretum, 9/20/2020 – Photo by Brad Guhr

Monarch Toxicity

This predator behavior was a surprising observation. Monarch larvae eat milkweed and sequester in the mature butterfly wings and exoskeleton the milkweed toxins called cardiac glycosides. These heart poisons can seriously affect vertebrate predators, including birds, and often cause them to vomit and subsequently avoid eating them further. However, these young kites not only ate monarchs all day Monday, but they continued their feeding frenzy the next morning. Either their stomachs weren’t too adversely soured, or the calories needed to continue this migratory journey were simply too important.

A Google literature review turned up no articles mentioning this habit of Mississippi kites eating monarchs. However, a follow-up conversation with University of Kansas biology instructor, Brad Williamson, helped me understand that this observation is not so irrational. He explained that the monarch population is not 100% toxic.

“The individual toxicity depends a lot on the particular milkweed species that hosted the larval stage. Asclepias syriaca (common milkweed) and Cynanchum laeve (honeyvine milkweed) are not nearly as toxic as A. verticillata (whorled milkweed). There is an entire range of toxicity and it makes for some great mathematical modeling questions–just how much toxicity (percent toxic) in the population is necessary for protection for the entire population? How much metabolic costs are there for monarchs trying to process highly toxic host plants? Turns out that only 25-40% of the population being toxic confers protection for the remaining population.” (I will include below a bibliography on monarch toxicity that Brad Williamson provided if any of you are interested as I am in learning more about this topic.)

There were a lot of interesting biological and ecological issues at play here with these monarchs and kites. It was just one more interesting natural history story with subplots to be observed by those of us living in the Monarch Flyway. Until I’m able to one day witness the hundreds of millions of monarchs wintering in the the Oyamel forests of central Mexico, I am completely content having a front row seat to this fascinating migration phenomenon right here in Kansas.

Monarch butterflies observed at the Monarch Butterfly Biosphere Reserve in Michoacán, Mexico. Video by Beatrix Amstutz, February 7, 2020.

Plant Milkweed

To assist the monarchs and their annual migration, plant milkweed host plants and other native nectar plants for adults. Check out our annual spring and fall Flora Kansas native plant sales.

Articles on Monarch Toxicity

  • Brower, L. P., and C. M. Moffitt. “Palatability Dynamics of Cardenolides in the Monarch Butterfly.” Nature 249, no. 5454 (1974): 280–283.
  • Brower, Lincoln P. “Avian Predation on the Monarch Butterfly and Its Implications for Mimicry Theory.” The American Naturalist 131 (1988): S4–S6.
  • Brower, Lincoln P., and Susan C. Glazier. “Localization of Heart Poisons in the Monarch Butterfly.” Science 188, no. 4183 (1975): 19–25.
  • Brower, Lincoln P., Peter B. McEvoy, Kenneth L. Williamson, and Maureen A. Flannery. “Variation in Cardiac Glycoside Content of Monarch Butterflies from Natural Populations in Eastern North America.” Science 177, no. 4047 (1972): 426–429.
  • Fink, Linda S., and Lincoln P. Brower. “Birds Can Overcome the Cardenolide Defence of Monarch Butterflies in Mexico.” Nature 291, no. 5810 (1981): 67–70.Malcolm, S. B., and L. P. Brower. “Evolutionary and Ecological Implications of Cardenolide Sequestration in the Monarch Butterfly.” Experientia 45, no. 3 (1989): 284–295.
  • Malcolm, Stephen B. “Milkweeds, Monarch Butterflies and the Ecological Significance of Cardenolides.” Chemoecology 5, no. 3–4 (1994): 101–117.
  • Malcolm, Stephen B., Barbara J. Cockrell, and Lincoln P. Brower. “Cardenolide Fingerprint of Monarch Butterflies Reared on Common Milkweed, Asclepias Syriaca L.” Journal of Chemical Ecology 15, no. 3 (1989): 819–853.
  • Nelson, C. J., J. N. Seiber, and L. P. Brower. “Seasonal and Intraplant Variation of Cardenolide Content in the California Milkweed, Asclepias Eriocarpa, and Implications for Plant Defense.” Journal of Chemical Ecology 7, no. 6 (1981): 981–1010.
  • Roeske, C. N., J. N. Seiber, L. P. Brower, and C. M. Moffitt. “Milkweed Cardenolides and Their Comparative Processing by Monarch Butterflies (Danaus Plexippus L.).” In Biochemical Interaction between Plants and Insects, 93–167. Springer, 1976.
  • Zalucki, Myron P., Lincoln P. Brower, and Alfonso Alonso-M. “Detrimental Effects of Latex and Cardiac Glycosides on Survival and Growth of First-Instar Monarch Butterfly Larvae Danaus Plexippus Feeding on the Sandhill Milkweed Asclepias Humistrata.” Ecological Entomology 26, no. 2 (2001): 212–224.

Insects: The little things that run the world

They pollinate 90% of the flowering plants on earth; and they eat plants, the crucial first step in changing plant energy into the fats and proteins that feed hosts of other animals. In so doing, insects sustain Earth’s ecosystems.  They truly are, in E.O. Wilson’s words, “The little things that run the world.”

Yet globally, insect populations have declined by 47% since 1974, a loss that translates into a decline in the very ecosystems that sustain all life on earth, humans included! 

https://www.audubon.org/news/yards-non-native-plants-create-food-deserts-bugs-and-birds

What can be done to reverse this trend? By restoring native plant communities in yards and gardens, we can help reverse insect losses and restore ecosystem health to our yards and gardens. 

Why native plants? In study after study, it has been shown that native plants host many times more insect species than do non-natives. 

Which insect groups are most important? In Nature’s Best Hope, author Doug Tallamy suggests selecting native plants that support two important insect groups: large, nutritious insects (think caterpillars of butterflies and moths) and bees. Caterpillars are the mainstay of most bird diets; and native bees perform the lion’s share of pollination. 

https://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/halictid_bees.shtml 

Where can I find resources for host plants native to my area?

Planting a diversity of native plants chosen for their ability to provide food for caterpillars and flowers for nectaring bees, ensures not only a prairie garden filled with a diversity of insects and birds, but also a garden that contributes to a healthier environment. And it is all happening right outside our door! 

Reference: 

Tallamy, Douglas W.  2019. Nature’s Best Hope: A New Approach to Conservation that Starts in Your Yard. Portland, Oregon: Timber Press.

Milkweed Pest: Oleander Aphids

Over the past few decades, there is an increased awareness of the importance of milkweeds for the life cycle of Monarchs.  More and more people are planting these native wildflowers in their gardens.  We closely monitor our milkweeds for monarch caterpillars and anxiously watch for the migrations in spring and fall.  We can even track the populations on Monarch Watch.  Milkweeds are vital to reversing the decline of this beautiful butterfly. 

However, large populations of small yellow insects that typically cover the leaves and stems of the milkweed plants are threatening this important wildflower species.  It seems like there are more of these tiny bugs every year.  This year, we have seen large populations of them on our nursery stock and throughout the gardens.  These oleander aphids (Aphis nerii) or milkweed aphids have become problematic. 

Oleander Aphids on Common Milkweed

Oleander aphids are not a native species, but were introduced into the U.S. on oleander.  They suck the sap out of stems and leaves, can cause flowers and pods to abort, and can even kill plants. They concentrate milkweed toxins in their tissue more effectively than native milkweed aphids, which makes them toxic to beneficial insects.  Like other species of aphids, their populations can explode in a short amount of time. When large populations are present, the plants will appear shiny due to the excretion of honeydew, which can also promote the growth of sooty mold.    

 As a milkweed gardener, what are your options?

Choose the right milkweed for your garden. 

Stressed plants will attract more pests.  Know your site and plant the right milkweed for your landscape. Swamp milkweed needs to be in a consistently moist area and butterfly milkweed naturally grows in areas with good drainage. Common Milkweed is very adaptable, but not for a formal garden. Plant common milkweed where they can spread and colonize a marginal area. There are many other species of milkweed that grow in sun to part shade and dry to wet. Continue to plant milkweed, but make sure it fits.  

Encourage beneficial insects

With the milkweed toxins in the aphids, beneficial insects tend to leave these pests alone.  This is a similar reason monarch caterpillars ingest the milkweed sap which makes them less prone to be eaten by predators. We have introduced parasitic wasp into the greenhouse to control these pests but that is not realistic outside that confined space such as your landscape. Lady beetles will typically eat aphids but they tend to shy away from these aphids.  

Don’t Fertilize

Let the milkweeds grow naturally in unamended soil.  Too much soil fertility will attract more aphids.  These aphids reproduce more quickly on plants that have high nitrogen concentrations.

Wait

Be patient as you wait for the natural processes to work.  Often, this is the hardest thing to do, because the plants are being adversely affected by thousands of these little pests.

Oleander Aphids on Whorled Milkweed

When these cultural practices have been unsuccessful, it’s time to take a more aggressive approach.  These are obviously not my first choices because they can also harm beneficial insects and even monarch caterpillars.  You must use as a last resort to save the plant.  Newly established milkweed plants may need some help the first few years until they get fully rooted.  Mature plants typically can fend off most of these pests.        

Squish

We have resorted to squishing the bugs on nursery stock.  These smaller plants are easier to manage by simply squeezing the affected parts of the milkweed plant between thumb and forefinger and drag along the stem. Use a glove or paper towel as you squish because it will get messy.

Squirt

Another option is to squirt the plant with a strong blast of water especially after you have squished the bugs.  Use a spray bottle of water or a jet of water from a hose. Focus the water on just the infested areas so other beneficial insects are not disturbed. 

Spray

The least optimum choice is to spray with horticultural soap or oil. Concentrate the spray just on the aphid colonies.  Use a piece of cardboard placed below the colony of aphids to minimize drift to other parts of the plant.  Again, this is a last resort option but may be necessary to save newly established milkweeds.   

Milkweeds are beautiful and essential native wildflowers.  They are under assault by these non-native pests.  Hopefully, you can get your milkweed plants through this onslaught of oleander aphids because they are so important for monarchs and other pollinators. 

Landowner Prairie Restoration Spotlight – Carolyn and Terry Schwab

Terry and Carolyn Schwab live on 109 acres in Eastern Harvey County affectionately known by a former neighbor as the “Foothills to the Flint Hills.” While much of the county land has been converted to cropland over the last century, the Schwab property has remained in remnant prairie.

We received a grant in 2004 to identify and study more than 100 prairie remnants in South Central Kansas and to collect seed for our 18-acre Prairie Window Project prairie reconstruction project on-site at Dyck Arboretum. Until 2010, this work helped us develop a prairie landowner network through which we consulted with landowners and assisted them with their prairie management needs. It was during these years that I had the pleasure of first meeting the Schwabs. Ever since I have enjoyed observing the dedication they bring to being prairie restorationists and natural area enthusiasts.

Terry and Carolyn Schwab and the property they manage (2007)

Increasing Wildlife Diversity

The property was a moderately overgrazed cattle pasture when they acquired it in 1993. The Schwabs’ main goal as land stewards was to increase wildlife diversity through improved habitat and enhance their avid hobbies of bird-watching and fishing.

The remnant prairie and emergent wetland above and around the ponds on their land can consist of hundreds of species of grasses, wildflowers, sedges, and shrubs. High plant diversity translates to high wildlife diversity. Maintaining diverse herbaceous vegetation also serves as a good surface water filter that improves pond health. Terry and Carolyn knew that without grazing or other forms of grassland management, invasion of a handful of tree species (including nonnative species) would create a dense, and comparatively lifeless, forest canopy within decades. Plant species diversity would decrease and wildlife habitat would suffer. They needed to become prairie restoration land stewards.

Dotted gayfeather (Liatris punctata) (Photo by Carolyn Schwab)

Vegetation Management

Controlling woody species and removing nonnative wildflowers became top priorities for the Schwabs in their quest to improve wildlife habitat on their property. Their initial efforts were extensive and laborious. They cut Osage orange and eastern red cedar trees and manually dug out musk thistle. To maintain water levels in the ponds, they repaired holes in the dams and removed trees whose roots can compromise dam life.

Numerous small trees invading in prescribed burning units A and B (2002 aerial photography)
Comparison with the previous photo shows that mechanical removal and prescribed burning have reduced tree cover over a six-year period, especially in units A and B (2008 aerial photography)

They were able to open up the upland areas where they had successfully removed mature trees and restore contiguous areas of grass and wildflower-dominated prairie. In these areas, the Schwabs implemented a regular rotation of mowing and prescribed burning to control any further invasion of woody plants. They networked with a local fire department to help them do this. They found mowing and burning to be much less labor-intensive than manual tree removal and effective tools for long term tree management.

Management Unit B, post-burn in 2009 (Photo by Carolyn Schwab)

Carolyn and Terry have made great improvements in restoring the prairie and emergent wetlands with tree management, but they know that they cannot rest on their laurels. Mature, seed-producing trees on their land and neighboring properties make keeping up with tree invasion a continual challenge. In addition to maintaining a routine of mowing and burning, they continue to cut and treat a number of invading tree species including honey locust, Bradford pear, Osage orange, Siberian elm, eastern red cedar, and the shrub Japanese honeysuckle. They are also on the lookout for the highly invasive, noxious weed sericea lespedeza which is becoming increasingly present in the area.

Conducting a prescribed burn on Unit C in 2010

Wildlife Monitoring

Carolyn invests a great deal of time monitoring and reporting on the biodiversity observed on their property. Daily walks to document bird populations, track phenology of flowering plants, and photograph butterflies are all part of what she sees as being an informed land steward.

Regal fritillary butterflies are dependent on habitat including diverse, large tracts of prairie. Even though the Schwabs have been improving the habitat of their prairie, regal fritillary numbers seem to be declining in recent years on a landscape scale. Carolyn has been planting nectar plants like butterfly milkweed and regal fritillary host plants (prairie violets) in the landscaping around her house to try and further support regal fritillary numbers.

This 2013 regal fritillary on butterfly milkweed (a yellow native landscaping variety near house) was the last one that Carolyn has seen on her property (Photo by Carolyn Schwab)

Carolyn is a top-notch birder. According to the Kansas Bird Listserv Database, a total of 329 species of birds have ever been documented as observed in Harvey County. Carolyn has seen more of these species (270) than anybody. And with easy access to 109 acres of prairie, wetland, woodland, and open water habitat, Carolyn has seen a whopping 232 of these species on her property!

A favorite experience of hers was witnessing a rare event on October 27, 2010. Eastern Harvey County is well east of the main sandhill crane migration flyway and seeing cranes there is not common. That night, however, the Schwabs observed 200+ sandhill cranes settle in for the night at their pond and enjoyed hearing their calls through the night. The cranes took off the next morning, but left behind a lasting memory for Carolyn.

Return of Butterfly Milkweed

The Schwab prairie restoration efforts are not only increasing the presence of grassland bird populations, but plant diversity as well. For years, they have not seen any butterfly milkweed on their property. But during the growing season of 2020, Carolyn reports that she has seen 20 plants.

Butterfly milkweed (Photo by Carolyn Schwab)

Protection for the Future

The Schwabs are considering registering their property with the Kansas Land Trust to protect this native prairie in perpetuity. By establishing a conservation easement on the property, Terry and Carolyn would be establishing guidelines for future landowners to follow that would help protect the prairie, watershed, and the diversity of species therein.

Thank you, Carolyn and Terry for your important prairie restoration land stewardship and for being willing to share your story.

A white-tailed deer doe and two fawns sheltering on one of the Schwab pond islands (Photo by Carolyn Schwab)

A Flint Hills Visit: Inspiration for Native Landscaping

The prairie and its Flint Hills environment at Chase State Fishing Lake (CSFL) provide serious inspiration for native landscaping. The CSFL vegetation, wildlife, substrate below, and the sky above collectively compose for me the most beloved and iconic landscape of native Kansas.

During my many past visits to CSFL, I have usually had an agenda that involved leading a tour group, collecting seed, or gathering butterfly data. I have never taken the opportunity to climb the bluff, sit in the prairie, listen to the grassland birds, observe butterflies and other pollinators, and watch the clouds go by. But I did just that on a recent Saturday in late June.

American lady butterfly on purple coneflower at CSFL

Pure Enjoyment

In addition to providing inspiration for native landscaping, visits to CSFL bring me pure enjoyment. During this recent visit, the steady breeze – with not a tree to stop it – was a reliable Kansas air conditioner. It kept me from thinking about the sweat-inducing effects of the hot sun. The puffy clouds overhead kept changing the light patterns and offered ever-fresh visual perspectives. In the midst of a surreal pandemic experience, when home and work routines are turned upside down and inside out, sitting on that prairie bluff was like visiting an old friend.

Big sky and clean water make CSFL a great place to fish or swim on a hot summer day

Desirable Wildflowers

The prairie wildflowers were plentiful during my visit thanks to a wet spring. The prairie plants we promote for the home landscape are in their native ecosystem here, with root systems that extend 10 to 15 feet into a matrix of limestone/flint/chert.

Rich images of plants like narrow-leaved bluets (white flowers) and lead plant (purple flowers) growing through rock are common at CSFL

In addition to a stunning display of orange and red butterfly milkweed (Asclepias tuberosa), other flowering species included tuberous Indian plantain (Arnoglossum plantagineum), narrow-leaved milkweed (Asclepias stenophylla), smooth milkweed (Asclepias sullivantii), green milkweed (Asclepias viridiflora), serrate-leaf evening primrose (Calylophus serrulatus), white prairie-clover (Dalea candida), purple prairie clover (Dalea purpurea), Illinois tickclover (Desmodium illinoense), purple coneflower (Echinacea angustifolia), narrow-leaf bluets (Hedyotis nigricans), catclaw sensitive briar (Mimosa quadrivalvis), and prairie coneflower (Ratibida columnifera). In your garden, these plants will attract monarch larvae (milkweeds) and other pollinators, fix nitrogen (legumes) and provide year-round visual interest.

Smooth milkweed at CSFL

Interesting Critters

The insects observed on flowers (including 17 butterfly species I noted) were plentiful. Spending time identifying and documenting insect diversity makes me want to see more of them in my landscape. Diversity of wildlife species is directly correlated to the diversity of plants in an ecosystem. Increase the diversity of flora and you will increase the diversity of fauna!

Wild indigo duskywings mating on lead plant at CSFL

In her last blog post, colleague Katie talks about the fun of identifying insects (The Mystery of the Orange Bug). I can certainly relate to the fun of trying to solve mystery insects.

The caterpillar pictured below is a new one to me. One of the identification tools and bio-networking platforms I’d like to use more is iNaturalist. Click HERE to see a couple of photos and help me with identification of this unknown (to me) caterpillar. One follower of this thread suggested the correct ID to be a salt marsh moth. I would have a hard time arguing otherwise.

Possibly a salt marsh moth on lead plant

Butterfly Milkweed

If nothing else, spending time at CSFL in late June will inspire you to fill your landscape with butterfly milkweed. It is harder to grow the same remarkable eye candy of this favorite prairie plant in richer and less well-drained soils. But in spite of my 50% success rate (at best), I keep trying. Never before have I heard somebody say that a prairie reconstruction or garden has too much butterfly milkweed!

Butterfly milkweed at CSFL

None of us will be able to completely recreate the open prairie of the Flint Hills in our urban landscapes. We can, however, take incremental steps in that direction with the plants we choose and the wildlife we attract. Visit Chase State Fishing Lake, absorb some if its good vibes, copy some of its elements with your plant selection choices, enjoy the wildlife viewing, and find new inspiration for native landscaping.

Click HERE for more of my thoughts about and photos from an earlier blog post about Chase State Fishing Lake.

The Mystery of the Orange Bug

As a lover of nature and all its small, crawly things, I often drop everything to observe and identify even the smallest bug. Much to the annoyance of my coworkers and volunteers, I just can’t give it up!

Learning to correctly identify the creatures around me brings a lot of fun and joy, but also:

  • Increases my scientific understanding of the world
  • Adds to my taxonomic and ecological knowledge
  • Builds empathy and compassion for the lives of smaller beings
  • Gives me a greater sense of place and familiarity in my Kansas homeland
This is the face of our little mystery. There were over ten of these orange bugs on a single plant!

Identifying the creatures around you is not always intuitive. Recently I found some small, orange, wiggly friends in the landscaping at my house. And so begins the mystery! Here are the steps and resources I always use to identify new-to-me bugs. Hopefully they can be useful to you as well!

Step One: Photograph

Make sure to quickly capture some detailed images of your friend. Life for a bug is fast paced — they are moving, flying, fleeing, eating or being eaten! You will need to have a good photo to refer to, as your search for answers may last longer than your memory.

I like to snap a quick photo with my iphone, but for tiny details I add a clip on macrolens. This one was very inexpensive and does a great job.

Insect or other?

Start by discerning whether you are a looking at an insect or something else. The word ‘bug’ is used to generalize all small, crawly things, but there are important distinctions. Spiders, for example, are not insects. Roly-polys are not insects. Earth worms are not insects. Counting legs and body segments of your specimen can help you determine if it is an insect; true insects will have 6 legs and 3 distinct body segments.

This diagram shows the 3 main body parts of an insect, and the characteristic 3 pairs of legs. Diagram from Wiki Commons

If you are a beginner and don’t know much terminology, use the easy picture-based and shape-based search tool BugFinder. My mystery friend could not be found on this form. They had 6 well-defined legs but no obvious body segments. I thought perhaps I was looking at a caterpillar (still an insect!), so I visited DiscoverLife and answered their beginner-friendly caterpillar search form. In the past it has been tremendously helpful, but not this time.

Step Two: Where is it?

Where is this individual living? If you can identify its preferred habitat, you have a huge clue to discovering its identity. My mystery bug was living and feeding on Scutellaria resinosa, (also known as skullcap), but nothing else around it. Many insects have a host plant (a specific food plant that the babies must eat) or host plant family. By knowing the plant, I can work backwards and find out what insects are likely to feed on or interact with it. Sometimes these interactions are called faunal associations.

When searching the web to identify a new insect, remember to include the plant it was found on and the region of the world you are in. This will narrow your search. I love to use the maps at butterfliesandmoths.org to see what species have been spotted in my area.

The blooms of Smoky Hills skullcap. Photo by Craig Freeman

Step Three: Ask and Post

If you have scoured the internet and all your favorite insect guidebooks, but still are stumped, it is time to visit BugGuide.net. They are “an online community of naturalists who enjoy learning about and sharing our observations of insects, spiders, and other related creatures.” There you will find a wealth of information on insects and their common whereabouts, but you can also post photos and ask questions of that expert group. They love to share their passion, and “to instill in others the fascination and appreciation…for the intricate lives of these oft-maligned creatures.” You may also find answers by posting a photo to your local naturalist Facebook groups.

And the bug is…

A shining flea beetle larvae, Asphaera lustrans! I finally found my answer by searching through the records at BugGuide.net and coming upon this page. While I can’t be sure, it was the closest match I could find. I also discovered that particular flea beetle hosts on Scutellaria, so I became even more convinced of its identity. I plan to post my photos and ask the experts on BugGuide to be sure.

Identifying wildlife and plants in your region is a lifelong pursuit; a never-ending puzzle. It can provide hours of stimulating entertainment for adults and children alike, and it will introduce you to like-minded folks who are also curious and engaged with world around us.

Next time you see a bug crawling across your porch or on your kitchen sink, don’t squish! Capture it, take a photo, release it outside, and begin the fun of unraveling its mystery!

Pollinator Week: Seen Through a Child’s Eyes

Children are naturally inquisitive.  We see it all the time.  Children marvel at the world around them.  They ask questions and are passionate about so many different things. 

At some point along the way as we grow up, that desire to learn and observe gets muted. Often, I find myself walking past the natural world to the next task, not taking the time to enjoy the beauty around me.  However, watching children around butterflies and other pollinators brings back the child in me. They marvel and are amazed by the smallest things, especially pollinators.

Pollinator Week: Pollinators, Plants, People, Planet

As we celebrate National Pollinator Week, I want to encourage you to look at these pollinators through a child’s eyes.  Slow down and watch the mesmerizing and beautiful work of pollinators.  If you have children or grandchildren, watch their eyes as they discover new things.  Their eyes are wide open and and their minds are ready to learn. 

Students conducting an Insect Sweep

Children are also our future conservationists, land managers and biologists. Adventures into the wild can be transformational for these youngsters.  We all know these connections to nature will plant a seed for the future. We need people who are passionate about the natural world and its management. And the younger we can develop those interests, the better.

So as you think about your garden and how you can save pollinators, think about your own transformative experiences. What was awe inspiring, what made you smile, and what had you never seen before? Simply having plants that attract pollinators will have an impact on pollinators in the present, but having people (you and your children or grandchildren) in your garden to love and appreciate them will save the pollinators into the future.