The green foliage in this picture is bush honeysuckle, which is an invasive species that dominates forest understories in Illinois. If not weeded out...
March 03, 2020

The management of Illinois’ forests has become an increasingly difficult task for landowners focused on maintaining and enhancing native plant diversity. I have often thought of it as a similar process to weeding a vegetable garden, with a diverse mix of our native forest trees as the vegetable crop and the weeds being everything from invasive species to some of the our native trees that tend to overpopulate or dominate woodlands without some type of natural disturbance.

This rhododendron shoot is infected with the pathogen Phytopthora ramorum, displaying the typical symptoms of ramorum blight. PC UI Plant Clinic
March 03, 2020

In early July, the Illinois Department of Agriculture submitted a press release detailing the detection of a new pathogen in Illinois that threatens our native oaks. This non-native pathogen is the causal agent for a very serious disease known as sudden oak death. However, there may be some good news in this incident, thanks to swift action by the agency and others to rapidly identify and quarantine infected nursery plants.

Newly planted urban trees are at risk of mortality if proper after-planting care, such as mulching and watering, is not carefully tended.
March 06, 2020

Spring is a time of an awakening plant world full of blooms and endless possibilities for the coming growing season.  It’s a time that many of us think about updating our landscaping, making it the most popular time of year to plant trees and shrubs. 

Ash trees have a distinctive, opposite branch arrangement observable by twigs that occur directly across from each other on each stem.
March 24, 2020

Trees represent some of the most long-lived vegetation in the landscape.  As such, these perennial, woody plants are also some of the highest valued plant material in our yards, parks, and urban areas.  Tree identification is an important first step in understanding the care of these invaluable plants that often take an entire human lifetime to develop into the mature, cathedral-like shade trees that line our city streets and shade our homes.

Spring Pruning Can Hurt Your Tree’s Bank Account
March 30, 2020

The beautiful warm weather this past Wednesday created an irresistible opportunity to get outside and observe the awakening plant world.  Woodland wildflowers are starting their spring show, which will peak over the come month or so.  The swelling, pink buds of redbud are a sure sign of the flowering display that will ensue in coming weeks.  In my landscaping, it was nice to see daylily patches and fall-planted bulbs start to push up those vibrantly green first leaves of the year.  Although a little too wet for much work, my vegetable garden is awaking with some unwanted green from the firs

Saucer magnolia is currently in full bloom in our area with an abundance of white to pinkish, showy flowers
May 05, 2020

Although spring was late coming this year, it has finally sprung, and with it both star magnolia (Magnolia stellata) and saucer magnolia (Magnolia x soulangeana) are in bloom.  These beautiful ornamental trees, native to Asia, provide about a month of spectacular flowers each spring.  They are some of the first landscape plants in our area to deliver such a showy display; truly one of the most endorsing signs that spring is finally here.

Apple trees in our area are in full bloom this week.  Unlike peach trees which suffered cold damage, many apple trees in central Illinois seem to have endured.
May 08, 2020

Winter injury is a common problem among fruit trees grown in our area and this year’s up and down spring temperatures resulted in damage to flower buds across central Illinois.  Cold weather in some years can bring damage to many ornamental tree species as well, impacting much anticipated spring blooms.  In fact, injury from cold weather is likely the most important limiting factor in plant species distribution around the globe, which is why most gardeners pay careful attention to cold hardiness maps.

Colorado blue spruce is a non-native, commonly planted landscape tree that suffers from many issues here in Illinois.
May 16, 2020

Spring is a great time for planting new trees in the landscape.  There is ample rainfall to support your newly planted specimen and the warming temperatures and mild weather motivate many of us to get out in the garden and plant things.  However, there are some commonly sold trees that fall onto my “do not plant” list.  Many such plants make my list for their invasive habit, but some are on there for insect or disease issues or just generally poor performance as urban trees. 

Native hawthorn trees are in full bloom this week with a canopy filled with tiny white flowers.
May 23, 2020

A properly planted and well located tree can last longer than a human lifetime, so tree selection is an important decision.

Sycamores across central Illinois are late to leaf out this year due to a commonly occurring fungal infection.
June 06, 2020

It has been another difficult spring for sycamore trees across central Illinois as near bare canopies of this tree stick out among the fully developed leaves of neighboring trees.  However, this doesn’t necessarily spell doom for your sickly looking sycamore.  It’s all caused by naturally occurring fungi that tends to ebb and flow with our spring weather over the years. 

This two-spotted bumble bee forages pollen on the flower of a spirea shrub
June 26, 2020

This past week was National Pollinator Week, a time set aside to celebrate the amazing and monumental task that pollinators perform each and every growing season.  Worldwide, animals pollinate about seventy-five percent of all plant species, and about ninety percent of all flowering plants.  And we all know that it takes a pollinated flower to produce so many of the fruits we depend on in our human diets, with animal pollination being responsible for about one of every three bites we take each day. 

The alien-looking fingers protruding from these crabapples release spores that can infect trees in the juniper family to perpetuate cedar-apple rust disease.
July 11, 2020

Whether its fungi, bacteria or even viruses, one of the most important aspects of plant disease management is stopping or limiting the spread of infectious pathogens.  I have always been fascinated by the way these tiny organisms, rarely visible to the naked eye, make their way through nature to infect new plants.  Many of their stories sound like something out of science fiction, often involving multiple species or special adaptations to enter and infect their host. 

This pin oak tree tested positive for bacterial leaf scorch and displays the most distinctive symptoms characterized by brown leaf margins, a colorful band and green tissue along leaf veins.
August 28, 2020

Shade trees are some of the most valuable plants in most urban landscapes.  They provide energy saving shade as well as valuable habitat for wildlife in a sometimes otherwise inhospitable built environments.  However, a mature shade tree takes considerable time to develop the canopy and branch structure that provides such benefit, which is the primary reason their high value when weighed against other landscape plants.  So, it pays to identify tree ailments effectively in the interest of protecting our investment in time and tree value.

Bald cypress is an Illinois native plant only know to occur in extreme southern Illinois. While it does wonderfully when planted here is central Illinois, should it be considered native?
September 05, 2020

The term native often means different things to different people.  Most definitions draw a line between geography and time scale which typically is demarcated by the point of human intervention or influence on the landscape. I really like this definition from the Forest Service in 2012, “A native plant is an endemic species that occurs naturally in a plant community, ecosystem, ecoregion, or biome habitat without direct or indirect human involvement.”

September 14, 2020

Do you have a tree that is displaying fall color right now?  Although it may be beautiful, this may be a sign of health issues.  In our area, most trees do not begin to change colors for the season until October.   A branch or two here and there or some yellow leaves in the canopy are not cause for alarm, but if the majority of your tree is changing color now, it may be a cry for help.

September 14, 2020

Have you ever wondered what the earth looked like when the dinosaurs roamed?  Humans didn’t realize that we have a living fossil among us that offers a glimpse into the past until the 1940s when the dawn redwood tree (Metasequoia glyptostroboides) was “discovered” by scientists in China.  This discovery has been noted to be one of the greatest for botany in the 20th century and the story behind the find is certainly a noteworthy tale in world history.

September 14, 2020

One of the most glorious aspects of fall is bringing in the apple harvest.  Every year around harvest time I wonder when exactly to pick my apples, which raises some questions.  What does the apple maturity chart say for this variety? Has the weather this year impacted fruit quality?  They taste pretty good, but are they still too small?  Taste is one of the best indicators, but there are several other signs you can observe to help solve the puzzle.

September 14, 2020

Over the past several weeks, our fall color has peaked here in central Illinois.  The stunning bright red to pink hues of red maple (Acer rubrum) were exceptional this year.  Who could miss the rainbow of color from sweet gums (Liquidambar styraciflua), covering yellows to orange-red and even purple, sometimes all on the same tree.  Beauty like this helps us overlook those pesky gumballs that sweetgum will deliver next spring.  Our State Tree, the white oak (Quercus alba), was especially beautiful this year with a seemingly larger red color among its typically ora

September 14, 2020

The Norfolk Island pine (Araucaria heterophylla) is a common houseplant that is often sold around Christmas time due to its Christmas-tree-like appearance.  However, in its native range, it is quite different than the 1-5 ft houseplant we know it as, reaching heights of 150-200 feet.  Although affectionately referred to as a “pine”, it is technically not a true pine (of the family Pinaceae) but rather a member of a separate coniferous family, Araucariaceae.

September 17, 2020

Winter is an excellent time for reflection on the past year’s growing season and any gardening successes or failures to account for next year.  In this season of seed catalog mailings and New Year’s resolutions, I have found it to be an ideal time to set gardening goals for the coming year during the down time associated with the shortest days of the year.

I have always found it motivational to first focus on what I can accomplish prior to leaf out and the coming growing season.   One of the primarily activities that can be done in the dead of winter is pruning. 

September 17, 2020

Recently, on a cold, single-digit day I paid a visit to the University of Illinois Plant Biology Greenhouses.  Since it was quite sunny and warm under the glass greenhouse roof, my mind drifted far from the snow and ice that was entrenched outside.  Nothing can beat the tropical ecosystem created in the Conservatory.  It was like a vacation to the tropics right here in Urbana, IL!  And to top it all off this facility is free and open to the public on weekdays.

September 17, 2020

Maple syrup is made from just one ingredient, maple sap, which magically flows from trees in late winter.  It takes specific weather conditions this time of year to create sap flow, caused by nighttime temperatures below freezing followed by daytime temperatures above freezing (ideally 20⁰F at night and 40⁰F during daytime).  The sugar containing elixir that flows from maple trees can then be boiled down to syrup or even further for granulated sugar.

September 17, 2020

Spring is a time of swelling buds and wildflowers in Illinois forests.  However, the flowering display of some plants may be overlooked if you aren’t observant.  

September 18, 2020

Evergreen plants, which retain their leaves (or needles) throughout the seasons, are some of the showstoppers of our landscapes in winter.  They provide some much needed color in a world devoid of the green, chlorophyll-laden foliage we have throughout the growing season.  Although evergreens do go into dormancy during winter, much like their deciduous cousins, their foliage is still subject extreme exposure over the winter months.

September 18, 2020

In the past week or so, crabapple trees have stolen the spring flower show among our blooming landscape plants.  These beautiful trees produce abundant flowers for up to 4 weeks each spring, with one of the best, most showy displays of any ornamental tree species.  They pick up where the magnolia trees left off, often flowering in close succession.  The beautiful, tiny flowers are produced from branch tips to the tree’s interior, creating a canopy of blooms.

September 18, 2020

Our native sycamore tree (Platanus occidentalis) is known for its extraordinary exfoliating bark which peels off to expose the beautiful creamy white and greenish colors beneath creating a camouflage-like appearance.  This summer many area sycamores are shedding bark at alarming rates which has prompted folks to question the health of their trees.

September 21, 2020

Anyone with a mature black walnut (Juglans nigra) on their property is likely aware that fruits are ripe now and the baseball-sized, green bombs are beginning to fall with each slight gust of wind or, at times, seemingly at random.  This native tree is prevalent throughout central Illinois, thriving on our deep, fertile soils to reach heights up to 100 ft.  When compared to other Illinois forest denizens it has some unique and interesting characteristics that set it aside from others.

September 21, 2020

Last weekend’s fall weather has certainly set leaf drop into motion for the year.  I noticed some of the early droppers stating to thin their canopy as many of the walnut around our property are already yellowing and loosing leaves.  Cottonwoods are half bare, dropping more leaves each time the wind blows.  One particular group of trees always draws my interest this time of year as I wait for their fall display - the deciduous conifers.

September 21, 2020

Illinois forests are dominated by a mixture of eastern deciduous forest trees and many of our urban areas mirror this forest composition creating a wonderful palette of fall colors each year as the growing season concludes and tree leaves senesce, giving way to winter dormancy.  As a tree-lover, this time of year is most definitely my favorite, from an ornamental standpoint.  It far outweighs the sometimes hard to detect spring flower structures that our mostly wind pollinated native trees produce. 

September 21, 2020

Everyone has their own idea of the perfect Christmas tree.  While I am not a person that picks the proverbial “Charlie Brown Tree”, I have certainly felt pity on the less attractive trees on the lot in years past.  Whatever your taste, a fresh cut Christmas tree adds a certain bit of nostalgia to holiday décor but takes a keen eye to select the right tree for your home, along with some forethought and proper care to ensure quality throughout the holidays.

September 23, 2020

Winter time is somewhat of a downtime for deciduous trees.  After a growing season’s worth of beautiful foliage, culminating in the wonderful fall display of color, woody plants enter the long, cold season of dormancy that is part of their annual life.  For many of us, this is not a time of arboreal beauty or great ornamental value, but rather a time of dull, bare tree canopies cast against our wintery skies.  However, I find winter as a time to reflect on one of the most often overlooked aspects of tree beauty, which lies in the character of their bark. 

September 23, 2020

The emerald ash borer (Agrilus planipennis) is an insect from Asia that has plagued our native ash trees in Illinois since 2006.  This pest was first introduced in 2002 around the Detroit area and has rapidly spread across Michigan and Indiana to infect most of Illinois today.  Sadly, the emerald ash borer will eventually wipe out our native ash species in Illinois as we know them, leaving a major void in our urban forests and natural areas since ash is currently so prevalent.

September 23, 2020

Winter is an excellent time for reflection on the past year’s growing season and any gardening successes or failures to account for next year.  In this season of multitudes of seed catalog mailings, I have found it to be an ideal time to set gardening goals for the coming year during the down time associated with the shortest and coldest days of the year.

I have always found it motivational to first focus on what I can accomplish prior to leaf out and the coming growing season.   One of the primarily activities that can be done in the dead of winter is pruning. 

September 23, 2020

In many communities there are iconic trees that nearly everyone recognizes and admires in passing during daily life.  The spreading, stately tree at the corner of University and Prospect Avenue in Champaign is certainly a historic and interesting specimen.  I cannot count the times that someone has asked me, “what kind of tree is that?”, nor can I count the times that I have sat at the stoplight on University Ave admiring that tree as I waited. 

September 23, 2020

Imagine spending years establishing and cultivating a beautiful landscape on your property, only for it to be destroyed in a heartbeat from a severe storm.  Couple that with a limb through your roof and you have a real disaster on your hands!  Who do you call?  What do you do about your roof?  How will your garden ever recover? In the past two weeks or so, Master Gardener Pam Hohn and her husband, Chris, have faced a steep learning curve on this matter following extensive damage from a recent tornado.

September 23, 2020

What kid doesn’t love those maple ‘helicopters’?  I grew up with two large silver maples (Acer saccharinum) in our yard and can always remember the late spring ritual of playing with one of the best toys ever produced by nature, the maple samara.  These winged seeds rapidly go from tiny flowers to mature seeds over the course of a just few months each spring.  I can remember playing with the odd looking seeds in so many ways as a kid, with their awesome helicopter action when falling through the air being the central component of most of that play.  

September 23, 2020

Historically, our part of Illinois has been more prone to ice storms than the northern or southern part of the state.  Based on over 50 years of weather data from the Illinois State Water Survey, our area of Illinois (including Springfield, Bloomington and Champaign) is likely to have an average of 5 days of freezing rain per year.  Whereas the rest of our state will only receive an average of 3-4 days of freezing rain. 

September 23, 2020

As you might imagine, my family spends a considerable amount of time out observing the wonders of the natural world, and I am always fascinated by the way my kids view and interpret things in nature. Many times, their straightforward and simple perspective makes me feel like such a dummy. There is certainly wisdom in their innocent perspective.

September 23, 2020

The management of Illinois’ forests has become an increasingly difficult task for landowners focused on maintaining and enhancing native plant diversity.  I have often thought of it as a similar process to weeding a vegetable garden, with a diverse mix of our native forest trees as the vegetable crop and the weeds being everything from invasive species to some of the our native trees that tend over populate or dominate woodlands without some type of natural disturbance.  

September 23, 2020

How many times have you been kept up at night worrying about a poisonous plant?  Hopefully, for most of us the answer to that question will be ‘not many’.  For better or worse, humankind has not always had a well-defined separation from the plant world as we often see today. 

September 23, 2020

Most folks think of spring as the ideal planting time for trees and shrubs.  However, fall offers a nice planting window with some added benefits over the spring season, making it my favorite time of year to establish woody plants.

Fall weather can create ideal planting conditions, with temperatures cooling off and roots requiring less moisture.  In addition, we typically get a good amount of fall rains to help ensure adequate soil moisture going into winter. 

September 23, 2020

Urban trees provide beauty and definition to our cities and most of us have a love and appreciation of these denizens of the boulevard and backyard.  In recent years, a body of research has emerged showing even greater benefits than previously understood to both the environment and our existence as humans. 

September 23, 2020

Fall color is beginning to paint tree canopies around central Illinois, making the next few weeks prime time for taking in the beauty.   Among our native trees, sweet gum (Liquidambar styraciflua), red maple (Acer rubrum) and sugar maple (Acer saccharum) typically get credit for the most beautiful and colorful display, but many of Illinois’ native oak trees put on a wonderful show of their own.

Honey locust can have large and terrifying thorns making it one of our spookiest native trees.
October 30, 2020

Images of witches, skeletons, and other specter abound this time of year.  But we really don’t need to look much beyond the natural world for a dose of spooky entertainment? This week, I’ve compiled my list of the top four spookiest native trees that all offer some great Halloween-related attributes everyone can enjoy on All Hallows’ Eve.

 Metal hardware cloth is a great material to protect young trees and shrubs from winter browsing wildlife.
November 21, 2020

Fall is an excellent time to add new trees or shrubs to the landscape and many of us have already taken advantage of mild weather and sunny days to get new plants in the ground.  With the lion’s share of work complete after digging, planting and mulching are finished, we often overlook some of the final steps to prepare new woody plants for winter.