Pine Diseases Changing Landscapes Forever

The Arboretum continues to change. If you visited the Arboretum in the early years, you would have seen many different types of pine trees and other evergreens planted in groves. These pine trees initially flourished, even though they are not native to Kansas. However, over the past 20 years, the Arboretum has lost many of those original pine trees.

This is not an isolated problem. Whole shelterbelts, specimen trees and screens have been decimated by diseases exclusive to pines. What are the most common pine diseases and what can be done to control their spread? That is a question I’m often asked and there are no easy answers. I do suggest Kansas State Extension and online resources for more information.

Pine Wilt

Pine Wilt threatens to remove several pines permanently from the landscape. Discovered in Missouri in 1979, pine wilt is most serious on Scotch Pines but can infect Austrian and White Pines. Since that initial report, it has continued to move westward and has completely decimated all of the Scotch pines in the Arboretum.

Symptoms for Pine Wilt usually appear from August through December and cause the trees to wilt and die rapidly in a month or two. Trees may survive for more than one year but the result is always fatal. The needles turn from bluish-gray to yellow/brown and remain attached to the tree.

Several organisms play a role in the death of a tree. The pinewood nematode is transmitted from pine to pine by a bark beetle, the pine sawyer. Once inside the trunk, the microscopic worms feed on the blue stained fungi that live in the wood but also on the living plant cells surrounding the resin canals and water-conducting passages, essentially choking the tree. There are no highly effective management tactics. Dead pines should be promptly cut and destroyed before warm weather of spring. If this is not done, beetles can continue to emerge from the logs and infect more trees.

Austrian Pine dead from disease that will be removed this spring in the Arboretum

Other Pine Diseases

Foliar diseases such as Sphaeropsis Tip Blight (STB), Dothistroma Neddle Blight (DNB), and Brown Spot of Pines (BSoP) are caused by types of fungi that can infect both the new and old growth. Some of the species affected by these diseases include Austrian, Mugo, Scots, and Ponderosa Pines. The symptoms of STB appear on the current year’s shoots. As the new shoots emerge in the spring, they are susceptible to infection by the fungus. Any damaged area provides the spores a way into the tree. The spores are dispersed by water and require high humidity for germination and penetration of the host tissue. Both DNB and BSoP cause spotting of the needles and eventually premature defoliation. Transmission is again by water and moisture. In a year with many spring rains, the moisture can spread the spores like wildfire and many treatments are needed to keep them in check.

Treatment Options

These three foliar diseases can be treated with multiple applications of copper fungicides and Bordeaux mixtures in the spring and early summer. Treatments are costly and high pressure equipment is needed to project the spray to the top of the trees. It has been my experience that control of these diseases is difficult. Spray timing is critical, densely planted trees are highly susceptible, and infection occurs during excessive rainfall. Thinning trees and removing dead or diseased branches will prolong the life of the tree, but the best defense is to keep the trees healthy by providing adequate moisture and fertility.

Diversity is the Key

One of the key lessons we have learned from this experience is that diversity is vital to a successful landscape. Whether pine trees, deciduous tree, perennials or shrubs, don’t put all your eggs in one basket. Establish a variety of plants adapted to your landscape rather than just one or two species. The truth is that you can do everything right and still lose an evergreen tree. Replant with a diverse variety of species so your whole landscape will not be open to widespread devastation again. There will be other diseases that come, but diversity will give you the edge.

Other Evergreens

New evergreen species are being trialed for adaptability in Kansas, but at this time there are not many viable alternatives other than our eastern red cedar with cultivars such as ‘Taylor’ and ‘Canaertii’. Southwestern White Pine (Pinus strobiformis), Arizona Cypress (Cupresses arizonica), Black Hills Spruce (Picea glauca var. densata) and Pinyon Pine (Pinus edulis) are also viable options. Full descriptions of these trees can be researched on the internet or you can come to the Arboretum and view them in person.

Pines like Ponderosa (Pinus ponderosa), Austrian (Pinus nigra) and Scotch (Pinus sylvestris) have been taken off the recommended tree list because they are so prone to disease. I would highly encourage you to visit the Kansas Forestry Service website at www.kansasforests.org . Once there, choose your region to view a full list of recommended trees for your area along with other informative publications.

Southwestern White Pine
Southwestern White Pine
Arizona Cypress
Arizona Cypress
Arizona Cypress
Arizona Cypress scale-like needles

Ecological Resolutions

Down time over the holidays while turning the calendar to the new year always feels like a good time to set sights on things I want to do to make my life more enjoyable and feel more meaningful. Planning for and embarking on challenges can be a way of establishing new habits. This year, I would like to focus more on the Land (as defined in The Land Ethic) and my connection to it. I will call them ecological resolutions and delineate them into three categories.

Land Restoration

From the Dyck Arboretum grounds to a number of public and private lands in Harvey County, there are seemingly endless opportunities to practice ecological restoration on remnant or restored native plant communities. In a grassland ecosystem, those opportunities mostly involve reversing the progress of invading woody plants through wood cutting, prescribed burning, and mowing. Woody plant invasion is a real threat for prairies today that involves regular maintenance and effort.

Woody plant invasion of the Flint Hills prairie over a 29-year period. (Courtesy of Tony Capizzo, KS Chapter of The Nature Conservancy)

Luckily, the action of wood cutting means being outside, getting exercise, creating firewood, and having fun in the process. I have fond memories of firewood cutting outings as a kid with my siblings, parents, and grandparents. While I don’t currently heat my house with wood, I have friends that do and perhaps we’ll work out some sort of bartering arrangement.

Such efforts also liberate prairie. The subsequent vigorous flowering response of grasses and wildflowers once they are released from the stifling effects of shade is what we are ultimately trying to achieve. That is probably for me the most gratifying part (even if it takes a year or two) of the whole process.

A 2009 post-burn crew at Sand Prairie in Western Harvey County (photo by Max Voran)

Selective removal of invasive/exotic wildflowers or grasses, brush mowing, conducting prescribed burns, collecting seed, and planting seed are also very worthwhile land restoration activities. This would be one of my top resolutions and a realm in which I would like to spend considerably more time in the coming year.

Wildlife Education

In a native plant garden or seeded restoration plot, we have some idea of what plants to expect to see blooming and setting seed because of our own work and preparation. The wildlife attracted to these developing plant communities, however, is much more of an unknown occurrence. I am fascinated by and motivated to learn more about the wildlife species attracted to native plant communities.

Regal fritillary butterfly nectaring on tall thistle flowers at a restored prairie near Hesston

It has been incredible to see cause and effect play out so clearly with regard to planting native plants and drawing in wildlife. These host plants and their flower nectar and seeds really do attract critters. From small gardens to larger restoration prairies, I’ve observed the influx of insects, small mammals, amphibians, birds, and reptiles, both plant-eaters and predators, in a relatively short timeline. Even when that short timeline is years in the making, the reward of seeing those wildlife species come in makes me want to install even more native plantings.

Just like anything else, building skills and knowledge in wildlife identification takes time and practice. But learning and appreciating the visual, auditory, ecological, and life cycle traits of wildlife species can be so interesting and rewarding. So then is the photography and story-telling of these species to try and inspire other people around you to plant native plants and try to attract wildlife to their landscapes as well.

I participate regularly in two events happening locally with regard to data collection of birds and butterflies. They are the Harvey County Christmas Bird Count and the Harvey County Butterfly Count. You can read more about each via the respective links and we are always welcoming new folks interested in participating. Experts lead the two counts that are great events for novice participants to learn a lot of information in a short amount of time. Organized by the National Audubon Society and North American Butterfly Association, respectively, bird and butterfly counts can be found abundantly in nearly all 50 states.

Harvey County Butterfly Count accessories

Not only do I want to commit more time to bird and butterfly citizen science, but I would like to invest more time studying insects in general. Heather Holm has published excellent books on pollinators, bees, and wasps that are educational and inspiring.

To be inspired by a great prairie ecologist that photographs and writes about wildlife regularly, I would highly encourage you to follow a blog produced by Chris Helzer of the Nebraska Chapter of The Nature Conservancy.

Urban Native Landscaping

Enhancing the urban landscapes in which we live, work, and worship with native plants can be perhaps one of the easiest and most rewarding of activities we promote here at Dyck Arboretum. I could always enjoy spending more time on this particular resolution. Adding a handful of native plants to even the smallest of areas can do wonders – both for increasing biological diversity in your landscape and for increasing your connection to the land.

Penstemon, spiderwort, prairie onion, and phlox blooming behind potted plants in my backyard in early June

Dabbling with native plant gardens in my home landscape is a labor of love in almost all months of the year. Of course, you have the popular processes of planting and watching for pretty flowers that everybody loves. But I also enjoy the time spent in these gardens weeding, mulching, picking flowers for bouquets, collecting seed or dividing plants for friends, chopping down the old vegetation, and building garden borders. It is time enhanced with the delights of observing all sorts of plant-animal interactions. I am outside and unplugged. This practice during the pandemic has been critical for helping me stay sane and grounded.

If you follow our Dyck Arboretum blog, you hear plenty on this particular ecological resolution, so I’ll keep this one brief. If you are new native landscaping, or are looking ways to enhance your native gardening process, consider following some of the best management practices suggested HERE.

Join Me!

Perhaps you would care to join me on any part or all of this quest? I’m always looking for prairie restoration and wildlife watching companions. Spending time with these ecological resolutions will add value to your life and may even enrich the natural environment around you in the process. You won’t regret it.

“Ecological restoration also involves restoring our relatedness to the wild.” ~Dwight Platt

Considering Caring for Common Ground

I am going to pull back the curtain for you regarding the potential development of some programming here at Dyck Arboretum of the Plains. This fall we have begun considering an initiative called Caring for Common Ground. Although we already promote in general the concept of “Caring for Common Ground” through much of our programming at Dyck Arboretum, we want to make the process with our membership more intentional.

Oak savanna seed collecting at Holy Wisdom Monastery. Collecting seed is an important and meaningful ritual in ecological restoration

Formalizing a Concept

The thoughts of the land conservationist, Aldo Leopold, have long been very influential to me and my work. In answering the question “What is a Land Ethic?” the Aldo Leopold Foundation offers the following:


“Ethics direct all members of a community to treat one another with respect for the mutual benefit of all. A land ethic expands the definition of “community” to include not only humans, but all of the other parts of the Earth, as well: soils, waters, plants, and animals, or what Leopold called “the land.” In Leopold’s vision of a land ethic, the relationships between people and land are intertwined: care for people cannot be separated from care for the land. A land ethic is a moral code of conduct that grows out of these interconnected caring relationships.”


Three years ago, we formalized a new mission statement: Dyck Arboretum of the Plains cultivates transformative relationships between people and the land. The concept of and language surrounding Leopold’s Land Ethic was foundational to the development of this new mission statement.

Growing the Land Ethic plaque on the grounds at The Aldo Leopold Foundation

Retreat to Wisconsin

Cheryl Bauer-Armstrong helped conceive and for 30 years has run the Earth Partnership Program at University of Wisconsin-Madison. Subsequently, the Earth Partnership for Schools Program that Lorna Harder and I co-facilitate in Kansas comes from Cheryl and the Earth Partnership Program. So, when the revered Earth Partnership team of Cheryl, Claire Bjork, and Greg Armstrong, plus Amy Alstad at Holy Wisdom Monastery, invited us to a conference called Caring for Common Ground (CCG) that had been years in the making, we couldn’t resist attending.

The Shack

Our Kansas team started by making a pilgrimage to The Shack, featured in the landmark book, A Sand County Almanac. This is the place where Aldo Leopold developed some of his thinking about The Land Ethic. We enjoyed visiting the place where many of his stories in the book took place. Walking prairie restored by the Leopold family and that is maintained today by staff at The Aldo Leopold Foundation. It felt like hallowed ground.

Our group (Kendra Flory, Lorna Harder, Karen McCabe-Juhnke, and John McCabe-Juhnke) taking in The Shack and Aldo Leopold’s restored prairie
John and Lorna birding along the Wisconsin River near The Shack
Kendra, Lorna, Karen, and Leopold Foundation Education Coordinator, McCale Carter (our tour guide for the day) taking turns reading the “The Good Oak” on the spot where that tree once existed

Conference at Holy Wisdom Monastery

We then drove 45 minutes south of The Shack to the Holy Wisdom Monastery where our conference would take place. The Benedictine sisters there are undertaking serious land stewardship on their grounds. Under the guidance of Greg Armstrong in past years and Amy Alstad in the present, volunteers are restoring many acres of tallgrass prairie and oak savanna. These restoration project areas were our learning grounds for the CCG conference.

Conference days started with gratitude, calm reflection, and hilltop views overlooking restored prairie and Lake Mendota
Karen and John McCabe-Juhnke collecting seed of bottlebrush grass
Planting seed in a degraded oak savanna
Cheryl Bauer-Armstrong (center) leads a post-planting sharing circle. The other CCG Conference leaders are from far left, Amy Alstad, Greg Armstrong, and Claire Bjork

Our conference activities involved observation and assessment of the present conditions related to soils, vegetation and wildlife. We acknowledged the past removal of Indigenous Peoples from these ancestral lands. A local Ho-Chunk tribal member served as an advisor for CCG and joined us for a session. There was discussion about the processes of land degradation that have been part of the site’s history. We reviewed ecological restoration techniques, conducted planning charrettes, and participated in seed collection and planting exercises.

Friends from Kansas and Wisconsin came together to practice ecological restoration techniques and develop a resolve for doing more land stewardship rituals going forward

Spirituality of Stewardship

Spirituality is an individual’s search for sacred meaning in life and recognition of a sense that there is something greater than oneself. Being a land steward restores ecosystem functions for the greater good through meaningful rituals. As a result, it can add value to one’s life, build a sense of place, and be a spiritual process.

Land restoration is inherently filled with ethical and spiritual dimensions. People from all religious and faith traditions certainly can bring value to this CCG process.

The writings of Leopold and Braiding Sweetgrass author, Robin Wall Kimmerer are influential to CCG. Kimmerer challenges us with the following question in our relationship to the earth. Should we be living in deep communion with the land, or looking to subdue and dominate it? Above all, this is an important question for land stewards to ask ourselves.

Pilot Study in 2022

We at Dyck Arboretum want to to do a pilot study of Kansas Caring for Common Ground (KCCG) in 2022. The first test cohort will be our small group that went to Madison. Arboretum staff, board members, and anybody that would like to help us Beta test this new program are welcome.

We envision that this will be a year-long study from January through December with one meeting per month. Homework could include individual reading, research, study and preparation for the next session. Monthly gatherings might include sharing, dialogue, and an interactive seasonal land stewardship practice. Such practices might include seed collection, prescribed burning, seed propagation, plant identification, chain saw work, planting, etc. An alternative to the monthly format for a larger group might include a one-time, whole-weekend KCCG retreat.

Regardless of format, a consistent framework for KCCG would include 1) A review of the site’s history (soils, hydrology, vegetation, wildlife, presence of Indigenous People, etc.), 2) An assessment of how conditions have changed over the last century or more, and 3) A land restoration plan for the future. Oh, and good food/drink would also be an important part of every gathering!

Going Forward with Intention

Finally, I’ll leave you with an image of the table that I sat around with friends after every evening of the conference. One adorned the table with interesting wood pieces collected from Wisconsin and Kansas that had been hand-cut, polished, stained and artistically crafted as candle holders. Another supplied delicious, slow food that came with thoughtful planning, preparation and cooking. Another provided spirited drinks with hand-harvested ingredients. It was a space filled with intention, meaning, adoration, and gratitude. May the coming year in study, conversation, and practice with Caring for Common Ground in Kansas be filled with similar such things for each other and with the land.

O Cedar Tree, O Cedar Tree

Here is a repost from a few years ago about using local cedar trees for your Christmas decoration this year, for the ecological benefits and the fun folksy style!

This past weekend I cut down a red cedar to use as my Christmas tree; just the right shape and size and with the right amount of character. I feel great about cutting one of these trees out of the wild (an Arboretum staffer condoning tree felling? Yes!). Red cedars are beautiful, strung with lights and tinsel, but they have become a real pest in the Great Plains ecosystem. Here are a few reasons to skip the plastic tree or spruce farm and simply cut yourself a cedar!

Any Christmas tree, cedar or artificial, can benefit from some ecologically conscious decorations. Dried grass and seed heads of prairie plants look magical amongst warm white lights, but are biodegradable.

Cedars have become invasive

Eastern red cedar (Juniperus virginiana) is native to Kansas and much of central and eastern North America. Native though they are, the USDA labels cedars as invasive, and rightfully so. Too many pastures and meadows are overgrown with cedars, choking out native grasses and wildflowers. Without natural wildfires and regular controlled burns, cedars have been allowed to flourish in places that historically would not have been suitable. The tallgrass prairie is one of the most rare and endangered ecosystems in the world, and the invasion of cedars upon open grasslands decreases species richness, changes soil composition and even threatens indigenous wildlife. If you are a landowner looking to do maintenance of your grassland or clear it of cedar trees, Dyck Arboretum can provide helpful information.

The woody plants in this photo have completely run amuck in a landscape that should be dominated by grass. Randy Rodgers has a wonderful essay here on the impacts of trees encroaching on the prairie.

Cedars degrade the prairie ecosystem

Grassland dependent birds, insects and small mammals become displaced or outcompeted when red cedars populate formerly open land. The University of Nebraska has compiled a lot of data on this subject at The Eastern Red Cedar Science Literacy Project, where you can find informative and alarming tidbits like:

“Grassland birds are the most rapidly declining avian guild in North America (Fuhlendorf et al. 2012) and are rarely observed once juniper exceeds 10% of land cover (Chapman et al. 2004).” (Twidwell et al. 2013)

and…

“An increase in overstory cover from 0% to 30% red cedar can change a species-rich prairie community to a depauperate community dominated by 1 (small mammal) species, Peromyscus leucopus.” (Horncastle et al. 2005)

Endangered and vulnerable species like the American burying beetle and the greater prairie chicken are only further threatened by the turnover of grassland to cedar forests. Cedars do have redeeming qualities – winter shelter and forage for birds, drought tolerance and erosion control. Red cedars certainly have their place in a hedgerow or small grove, but should be carefully limited from spreading.

Cedar trees make prescribed burning a little tricky, and can exacerbate wildfires by sending up flames much higher than other grassland plants do.
My coworker Brad has some great bumper stickers that encourage regular prescribed burns to prevent cedar overgrowth.

Cedars are a ‘green’ choice

For all the aforementioned reasons, cutting a cedar for a Christmas tree is already a very ecologically conscious decision. But there is more! Unlike plastic trees, cedars are biodegradable and can be used for firewood or garden mulch. Also note that conventional Christmas tree farms providing spruce or firs require lots of resources:

  • clearing/agricultural development of land
  • years of regular water input
  • pesticides to keep needles bug free
  • shipping and fuel costs to get the trees to distributors around the country

Why don’t we skip all that frivolous resource usage and cut down some of these pesky cedars instead? You can feel good about a tree that’s low on carbon waste but high in old-fashioned, folksy quality.

Get permission from a farmer, landowner or your county land management officials before you start cutting. They will likely be happy to get rid of one, and you may get it for free (more money for gifts, yippee!) and enjoy a lovely, cedar-scented home this holiday.

Army Worms

The Arboretum is under siege! An army has invaded, demanding we relinquish our lawns! Army worms, that is. These pesky creatures can cause major damage, and they unfortunately have a taste for fescue. Last week we came upon a sidewalk full of worms, crawling out of the lawn in search of more food. The grass was a sea of them, their tiny movements making it seem like the ground was alive.

Close up of a fall army worm Spodoptera frugiperda.
Army worms have a distinctive ‘Y’ marking on their heads
and are usually found feeding in groups.

To Spray or Not to Spray

I am always a big advocate of lassez-faire when it comes to controlling insect populations. After all, “plants are meant to be eaten”, right? And every insect has its place in the food web to keep our ecosystem thriving. I say this every time our members call asking about why their coneflowers have holes in the leaves, or why their Zizia has been defoliated. I tell them not to panic, that bugs are good to have in a garden, and that with enough good habitat natural predators will help keep the populations in check.

But when populations explode overnight, it can rightly cause concern. Native perennial flowers have deep tap roots that can reach 10 ft deep and beyond, which means they easily recover from a bit of nibbling. Fescue does not. The root zone is often less than 2ft, and in the heat of summer it can get even shorter. These little bugs can cause big damage! But luckily they rarely kill the grass. According to KSU Extension and Research, they don’t usually eat into the crown of the plant, rather move on to more tender greens. This means the plant can regrow and recover once they leave.

Fall armyworms seldom kill grass ---- rather, than nubbing a plant
down to the crown and growing point, larvae will select a more tender adjacent grass
blade to feed upon. Of course, under heavy feeding pressure, larvae may be forced to
feed deeper down on a plant, but usually, when the food supply becomes scarce or
"tough", the larvae will move "in mass" to adjacent areas where there is a "fresh stand"
of food to feed on.

- Kansas State University Agricultural Experiment Station and Cooperative Extension Service
Army worm damage looks a lot like drought stress at first glance. The grass turns patchy and brown.
This lawn was green and lush 72 hours before this photo was taken, an example of how quickly these little worms can feed.
Fescue at the Dyck Arboretum, beginning to resprout on August 18, 3 to 4 days after the army worms have finished feeding.
Stay tuned for updates in the coming weeks.

Use a Targeted Pesticide

Insecticides containing acephate and spinosad are effective at killing caterpillars, but we opt for friendlier treatments since these are known to harm the bees, birds and butterflies that call the Arboretum home. To avoid unnecessary kill off of non-target insects, I use Bt: Bacillus thuringiensis. This is a biological pesticide that uses bacteria to infect the gut of the army worm. In the alkaline gut environment of insects, it turns toxic and gives them a terminal tummy ache. We also use this around the Arboretum to keep bagworm populations in check when they start to overwhelm our cedar trees. According to current research on Bt, it is non-toxic to humans, pets, birds, and fish. It also has a short life once sprayed, which means reapplication is necessary, but also ensures you aren’t killing more insects than you intended to.

Monoculture Dilema

This is the precisely the problem with monoculture lawns. They require consistent maintenance, chemical and physical, to achieve that uniform, western European ideal of ‘perfection’. As we consider seeding new grassy areas of the Arboretum, we may be looking to a fescue mix, or a seed mix that includes sedges and native grasses together. This means that if an infestation comes along, hopefully not all species in that mix will be palatable and leave some green behind while the rest of the species recover.

If you see a few army worms here and there, don’t panic. Only large populations require a chemical response. But to those of you who will encounter them by the millions this summer like I did, good luck!

Seeded Prairie Checkup

I recently did a seeded prairie checkup to see how our December 2020 sidewalk planting described in the earlier blog post “Seeding After Disturbance” is doing. I’ve been informally monitoring it regularly since spring and have been encouraged by the progress I’ve seen.

Sidewalk edge seeded planting site this week on 8/10/21
The same planting site on the day it was planted 12/28/20 w/ planters Janelle and Kendra

Good Germination

We’ve been lucky with the weather since this planting. Conditions to promote good seed germination have been excellent. Remember the deep freeze we had in February? While it tested our human resiliency and strained our heating bills, it was good for this seeded prairie. Adequate precipitation and freeze/thaw action commenced throughout February and March. These conditions helped work the seed down into the soil while also breaking down their seed coats to help prepare them for germination.

Warmer temperatures along with rains in April and May promoted good germination. Identifiable prairie seedlings from the planted species list identified in the earlier blog post were evident amidst the expected seedlings of annuals like ragweed, sunflower, and foxtail.

Annual sunflower, giant ragweed, and foxtail grass serve as a shading nurse crop for tender, young perennial prairie plants

Thanks to the planting areas’ proximity to a water spigot, I was able to do some supplemental irrigation during the hot, dry weeks of late June and early July to keep the new seedlings from burning up while the seedling roots were small. But periodic rains in July and early August along with mottled shade from the nurse crop of sunflowers and annual grasses provided the conditions needed to help the prairie seedlings get well established as we head into fall.

Species Identified

A brief perusal of seedlings during this week’s seeded prairie checkup helped me find and photograph 14 of the 43 species that were part of the Prairie Moon Nursery seed mix. My prairie seedling identification skills are rusty, but I was able to identify the following seedlings to at least genus and some to species.

Seedlings of these identified species are thick throughout the planting and I’m confident that a good number of the rest of the 43 species in the mix will also show up eventually.

Weed Management

Typical management for a less-manicured seeded planting is simply to mow it a couple of times during the growing season to keep annuals from going to seed. Since such an approach for a higher profile area near the visitor center may look a bit scalped and perhaps not as appealing, we are taking the approach of cutting or pulling stems of the annuals. It is more labor intensive than mowing but not an unmanageable approach for small sidewalk edge planting, and regular volunteer, Gerry Selzer, has cheerfully embraced this task.

This weedy sidewalk edge vegetation is shading and hosting a variety of prairie seedlings underneath
The rare and coveted Gerrius selzeranii

Attracting Insects

One of the main reasons for planting this diverse wildflower seed mix in addition to adding pretty splashes of flower colors, is to attract insects and biological diversity to our sidewalk edge prairie beds. In two or three years, these planted species will be flowering and attracting insects with their flower nectar and host plant vegetation. I look forward to engaging school kids and teachers with regular investigations of these sidewalk edges to learn more about relationship between prairie plants and insects.

A new black-eyed susan is already playing host to caterpillars, possibly of species of checkerspot butterfly

Overall, I’m pleased with the progress of this planting as seen during this seeded prairie checkup. Days are getting shorter and we are almost to the cooler months of this planting’s first year when I can be pretty sure that these young prairie seedlings will have deep enough roots to survive about any weather conditions. Stay tuned for future updates about the development of this planting and consider how you too might add a seeded planting somewhere in your landscape.

Tree Stress

This spring we have several trees showing signs of stress that are not particularly attractive.  Since last fall, something has happened to them.  They leafed out late and/or they have some dead branches throughout the tree.  More than likely, it is a result of the historic cold temperatures this winter.  But it made me wonder about some other reasons these trees may be stressed this spring. 

Why trees?

Trees in Kansas are a luxury and one of your property’s greatest assets. To sit under a mature tree on a warm afternoon, enjoy the blue skies and sip your favorite cool drink is a special experience.

Trees need to withstand the rigors of the climate. Trees block harsh winter winds, give you privacy, delineate boundaries, offer great fall color, attract birds and other wildlife that enhance your enjoyment or your landscape, and increase its resale value. Trees are important for all of these reasons and more, but they are not invincible. At any moment, signs of stress can emerge, so we need to understand and make every effort to alleviate problems that may arise. 

Open-grown burr oaks are wider than they are tall (Photo by Lamar Roth)

Tree Stress Symptoms

Stressed trees are easy to pick out in the landscape. Symptoms will manifest in a number of ways including flaking bark, secretions, distorted or missing growth, insects, foliage issues, dead branches and lack of vigor. 

These symptoms are visual clues to internal, external or environmental stressors. Left untreated, these stressors could ultimately kill your tree. Stressed trees are beacons to insects because they are weaker and vulnerable to attack.  Compounding factors over a number of years from the same stressors or multiple stressors lead to tree fatality. Here are some common causes of stress in trees. 

Poor Tree Watering Techniques  

It is true that trees need water to survive, but they need just the right amount of water.  Too much or too little can cause a tree to be under stress. These problems can be compounded when planted in our clay soils. Defoliation, yellowing of the leaves and branch die back are all symptoms to avoid. Most trees, if properly situated, can withstand seasons of drought without much extra inputs. 

Monitor trees during stressful times such as drought to make sure they don’t need a deep soaking. Keep in mind that waterlogged soils are more problematic than drier soils because proper air exchange by the roots in hindered by extremely wet conditions. Sometimes we see a tree under stress from drought and do more damage by giving it too much water. Give it a deep soaking, but let it dry out between watering.   

Install the tree properly 

One of the first lessons I learned as a novice horticulturist is how to plant a tree. “How hard can it be?”, you may say.  Just dig a hole, put it into the ground, water it for a while and watch it grow. More trees are killed by improper installation than you might realize. Choosing the right tree for the soil conditions, along with understanding mature size, will go a long way to helping that tree survive and thrive. 

In our clay soils, I plant the root flair a few inches higher than the soil line in a hole that is at least twice the size of the root ball. I make a small basin around the tree that makes it easier to water and then lightly mulch the basin. It is important to keep mulch away from the trunk of the tree. I stake the tree for the first year and remember to remove the wires that will eventually girdle the tree if forgotten.

For some additional tips on how to properly plant trees, check out my blog post “Steps to Planting a Tree”.

Beware Lawn mowers and Weed eaters

Anything you can do to keep mowers and weed eaters away from the trunk of trees is vitally important. I have seen too many tree trunks damaged by mowers bumping them and people string trimming around the base of the tree, trying to cut down every sprig of grass. A small two to three foot mulch ring provides just the right buffer between the trunk and lawn.  I have seen a string trimmer completely girdle the soft bark of a maple tree and kill it in a couple weeks. If you have invested in a tree, protect it from these tree killers.   

Mulch Around Trees Properly

The advantages of mulch around trees are obvious. It is one of the easiest things to do and it improves the aesthetics of the landscape. However, too much mulch, mulch touching the trunk, or mulch volcanos around your trees could cause major tree stress. These stressors are totally avoidable with one to two inches of mulch around the trunk, but not touching the trunk. It is important to keep the mulch several inches away from the trunk. Too much mulch will cake up and seal off the soil, impeding proper air exchange by the roots.    

Too much mulch piled up at the base of the tree can lead to fungus, rot, low oxygen levels and tree death.
This is an example of a mulch volcano. Be sure to pull mulch away from trunk of tree and spread out.

Improper Tree Pruning

Pruning your trees as they mature is a necessary function. I generally prune our deciduous trees during the winter when they are dormant, making sure not to remove more than 1/3 of the growth at a time. Proper timing will allow the tree to begin to heal without opening up the tree to potential diseases and pests. Evergreen trees can be pruned any time but I avoid the hottest part of the year.   

Construction Injuries to Trees 

Trees often suffer during and after construction projects. Compacted soils and branch or trunk damage can stunt the growth for several years after the project has been completed.  It often takes years for compact soils to improve.  I killed several nice maple trees after our Visitor Center was constructed because the soil was too compacted.  The soil would not drain and they were essentially planted into an undraining bowl.  The roots were completely surrounded by water and they drowned and stunk when I pulled the dead trees out.  Remember to protect/ fence off any trees you want to save during a construction project. 

Environmental Injuries

There are so many nice trees and shrubs from which to choose. We often push the hardiness zones to grow trees that are borderline hardy in our area. As I mentioned earlier, we have a sawtooth oak and gingko that suffered damage from the extreme cold earlier this year. The are coming out of it, but they will look tough for a few years. These trees are not native and remind me to choose native plants first. It also reminds me to be aware of the hardiness of plants we install. Match plants up to your site, including sun, soil, exposure, hardiness, mature size, and moisture.

Sawtooth Oak winter damage

Trees are resilient, but we can help them by considering their needs. A little homework before planting can alleviate problems through the years. Trees are alive and ultimately affected by so many factors, some of which are out of our control. Who know what the next pest will be? Who knows when the next drought will occur? All we can do is try to create/match an environment conducive to growth.

Buffalograss Seeding Experiment Update

Last November, I set out to establish buffalograss a different way than I have traditionally done. Normally, I have areas prepared this time of year for buffalograss seeding. May and June are considered the best time to plant buffalograss because it is a native warm season grass.  It needs to be planted when soil temperatures are above 60 degrees.

In South central Kansas, it is recommended that seeding of buffalograss be completed no later than August 15. Later seeding is not very successful because the newly germinated seedlings do not get fully rooted before winter. That has been a good rule of thumb, but requires so much water in the summer to get the seeds to germinate.

With this new approach, one plants the buffalograss seeds along with annual ryegrass in the fall or early winter. In theory, the annual ryegrass, a cool season grass, will germinate and hold the soil through the winter. The buffalograss seeds will work their way into the soil with the natural freeze/thaw of the soil throughout the winter. These seeds will then germinate the following spring on their own with annual rainfall and warm 60 degree soil temperature. 

Area before planting, November 2020
Annual ryegrass mowed for the second time this spring.

Update

The buffalograss is starting to germinate. I have not irrigated it this spring, which is a huge time and money saver.   Over the next few weeks, I will monitor it for dryness. Beneficial and timely rains have allowed the seed to germinate on its own. Essentially, this process mimics the natural seeding process. 

In the center of the image, is a buffalograss seedling.

We are mowing the annual ryegrass weekly.  It is important to keep the canopy open so the sun warms the soil, allowing the buffalograss seeds to continue to germinate. The seeded annual ryegrass will expire on its own as we move into warmer summer temperatures. As the ryegrass dies, the roots continue to hold the soil. Buffalograss will then be able to spread and fill in the area through the rest of the summer.

What I would do differently

  • Reduce the seeding rate of the annual ryegrass: It is recommended that you plant 3-4 lbs./1000 sq. ft. I would only seed 2-3 lbs./1000 sq. ft. The seeds will still germinate to hold the soil through the winter, but not be so dense that they shade out the buffalograss seeds in the spring. 
  • Plant buffalograss seed first and slightly cover it: I had some buffalograss seed float off the soil as I established the annual ryegrass seed last fall. 
  • Start the process earlier in the fall after the first freeze (October 15):  It would have been better to get the annual ryegrass established with slightly warmer temperatures, but not so warm that the buffalograss seed germinates. 

I will continue to monitor the progress of the buffalograss planting.  For smaller areas this seems to be a viable alternative to the traditional buffalograss planting. There are additional costs with the purchase of the annual ryegrass seed, but you save so much time and water compared to the traditional seeding method. Look for another update on the buffalograss seeding in a couple of months as the buffalograss begins to spread.     

Weed Profile: Dame’s Rocket

As stewards of our landscapes, we need to be constantly vigilant as we monitor for problematic weeds and invasive species.  We have some usual culprits such as bindweed, bermuda grass, Johnson grass and Bradford pear trees.  However, I have noticed another subtle spreader that is quite attractive but quite pushy – Dame’s rocket. 

For years, I have been monitoring a growing population of Dame’s rocket in one of our bordering hedgerows.  It is beautiful right now with its bright purple blooms, but don’t be fooled. This desirable plant will wreak havoc on the natural environment if left unchecked.  Larger populations will even threaten the survival of native plants and degrade habitat and water quality.

Dame’s Rocket in full bloom

Dame’s rocket (Hesperis matronalis) is a tall, annual, biennial or short-lived perennial, which produces either white, pink or purple flowers in the April and May. It was introduced to North America in the 1600’s from Eurasia. The attractive blooms have made it a garden favorite. It is often seen in roadside ditches, hedgerows, older farmsteads. However, in recent years, Dame’s rocket has gone rogue, moving from yards and garden plantings into adjoining landscapes.

Phlox’s Doppelgänger

From the Mustard family (Brassicaceae), this weed resembles tall garden phlox in height and color. However, Phlox is in the Phlox family (Polemoniaceae). Perhaps the most distinguishing difference between the two is that Dame’s rocket has four petals, while phlox has five. As part of the mustard family, it produces an abundance of seed. These seeds are dispersed by mammals and eaten by birds. When the seed pods ripen, they shoot seed in all directions, including the coats of wildlife. These mammals unknowingly spread the seed to nearby waterways, hedgerows, pond edges, and maybe your landscape. Dame’s rocket is reported in most states equal or north of Kansas longitudinally. It is reported as invasive in CO, CT, IN, MD, MI, NJ, PA, TN, VA, WI, and WV.

Dame’s rocket spreading from it’s original colony

Dame’s Rocket is closely related to other problematic weeds of the mustard, family such as garlic mustard, hedge mustard, wild radish and yellow rocket. All of these weeds are prolific and opportunistic, infesting field margins, woodlands, open grassland and wetlands.  It appears to have allelopathic tendencies (the ability to produce chemicals that prevent or reduce the growth of other plants) similar to garlic mustard. With these tendencies, Dame’s rocket and garlic mustard will quickly form dense monocultures within a few years, pushing out other desirable native plants.  As has happened to our little planting, it quickly colonizes by spreading in every direction. 

Garlic Mustard

Controlling Dame’s Rocket

To control Dame’s rocket, pulling before it produces seed is the best option if the population isn’t too large.  Make sure to remove the whole plant roots and all. Discard the plants in the trash. 

Spraying is another option with a 2,4-D product. A systemic herbicide applied as a foliar spray can be effective. Herbicide is best applied to the basal rosettes (low round clumps of leaves) in late fall or early spring, when other plants are dormant. Always read and follow the directions on the label when using herbicide. Any plan must also be mindful of desirable native plant species and habitat conditions in a targeted location that may be vulnerable to herbicide uses. This is a reason to spray as a last resort. Cutting or mowing can also prevent seed production and spread until other management techniques can be initiated.   

Over the past few years, I have changed my tune regarding Dame’s rocket. As beautiful as Dame’s rocket may appear, it is an invasive species with the potential to damage entire natural ecosystems. I used to say, it is doing no harm growing in the hedgerows. Those are just waste areas that need a little beautification, I thought. Then I started seeing it in other small populations away from the original colony.  Be on the lookout for it and take action before it spreads and really becomes a problem in your landscape or your neighbors landscape.

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.