Extreme winter cold is something that can keep gardeners up at night. Since plants are dormant, there is little we can do in the way of plant health care and that can be a real helpless feeling. The extremely cold weather back in December certainly raised concern and my office received a number of calls from worried gardeners.
Last month, the US Forest Service released a technical report titled, “Climate Adaptation Actions for Urban Forests and Human Health.” The report includes a summation of the current research related to urban trees and climate change, looking at how trees benefit human health, how climate change is impacting urban trees and how we can help our urban forests adapt.
Deicing salts are essential to winter travel in Illinois and provide necessary safety in a landscape setting by melting dangerous ice on precarious steps, sidewalks, entryways, and other areas of frequent foot traffic. However, winter damage from salt can be a major problem in some landscapes by negatively impacting plant health or sometimes outright killing plants from overexposure.
Rock salt for snow and ice
Rock salt, or sodium chloride, is the most commonly used deicing agent. It is relatively inexpensive, very effective, and widely available.
Freezing rain is a regular part of winter weather patterns in central Illinois, resulting in occasional ice storms that can damage property, take out utilities and wreak havoc on tree canopies. By meteorological definition, an ice storm occurs when ice accumulation is greater than 0.25 inches. On average, our area of Illinois experiences about 5 days of freezing rain per year which rarely result in an ice storm, but can nonetheless cause major damage in any instance.
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.
There are so many plants in nature that tend to reveal themselves during some kind of phenological event, such as flowering or fruit set, and then scream for attention. For example, consider Joe-pye weed (Eutrochium purpureum), which one of my favorite native wildflowers, frequenting the partial shade of woodland openings and edges on drier sites.
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.
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.
Invasive species can be characterized as any non-native species that is introduced to a new location, has the ability to spread and causes some kind of harm. Across Illinois and around the globe, invasive species cause significant ecological and economic damage each year. In the ever globalizing society we live in, these exotic invaders are a result of either accidental or intention mixing of biota around the planet. Humans have a long history in this mixing process and as we have become better and better at moving around the planet, the rate of invasive species introductions has parall
As the local food movement has grown in popularity, an interesting subset of “foodies” have emerged that forage in nature for their dinner. Many native, wild plants are edible and these folks seek them out in our forests, prairies, and sometimes even our yards.
Not all trees shed their leaves in coordination during fall. You may have noticed that some trees are still holding their leaves this week, and many of those will likely hold them until spring.
Each winter, I get a number of questions on this topic as folks ponder the “not-so-deciduous” deciduous tree in their landscape. Are these trees considered deciduous or evergreen, or somewhere in the middle?
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.
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.
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.
The eastern prairie fringed orchid (Platanthera leucophaea) is perhaps one of the most beautiful native prairie flowers in Illinois. Its delicately fringed, white flowers gently unfurl from the bottom to the top of its inflorescence over a 7-10 day period during late June and early July in Illinois prairies, but only if conditions are right. This plant is quite sensitive to annual fluctuations in weather which greatly influences flowering each year. In good years, up to forty beautiful blooms may adorn flower spikes that reach high into the tip-tops of the prairie to lure in pollinators.
A startling report on global biodiversity was release by the United Nations this week noting an alarming trend in worldwide species extinction. We, humans were pegged as the primary cause of an increase in extinction rates to the highest levels in human history. Specifically, around 25% of the species assessed are threatened, suggesting that one million of the eight million known species of plants and animals are at risk of extinction.
This past week, many folks around Champaign-Urbana and surrounding areas may have noticed plumes of white smoke gently rising in the distance or caught the scent of what seems to be the well-known smell of a campfire. It is special time of year when a tiny window of time emerges for the application of ecological burns to promote the health and diversity of native plants in many of our local natural areas. This practice is by far one of the most important processes that natural areas managers can recreate in parks and preserves to boost the health of prairie ecosystems.
It’s beginning to feel more like spring and I know that many of us are anxiously awaiting the awakening of the plant world. Although we all know spring is sure to come, it would be nice to have some assurances on the timing and date of warm weather’s arrival. Unfortunately, that’s just not possible without a truly working crystal ball. However, there is some very important information about the seasonal habits of plants we can surmise from collection of phenology data from year to year.
In our increasingly globalized society, invasive species have become somewhat of a way of life as we continuously intermix the world’s biota. Plants and animals from other continents tend to find their way to our landscapes and often are here for good. As a gardener, it’s difficult to keep up with the pace at which new invasives pop up. It’s even more difficult to figure out what these invasives mean to our home gardens and how they may impact our future plant choices.
The Fourth National Climate Assessment was released last fall in two volumes, containing information about how climate change is affecting the physical earth system across the US and a detailed assessment of how those changes now, and in the future, will impact our country. The report documents aspects of climate change already measured across the US and paints a dismal outlook, with climate change occurring faster than projected by past assessments.
The USDA Plant Hardiness Zones are a standard that most gardeners consider when selecting plants suitable for their local climate. These maps show us the mean annual low temperature for a given location, which helps distinguish the relative cold hardiness of plants, insects and other biota.
Last week, I reviewed the history of USDA Plant Hardiness Zone Maps (PHZM) and their relative change over recent time. These maps are intended to be a guide for gardeners attempting to predict the potential for winter injury to plants, which is a key factor in establishment and successful cultivation of woody and herbaceous perennial plants. This week, I will look at how gardeners should interpret these maps now and in the future as the impacts of climate change accelerate.
This week marks the half way point for the 2018 Illinois Ginseng Harvesting Season, which runs from the first Saturday in September through Nov 1. Did you even know that ginseng grows in Illinois, let alone the fact that there is a regulated harvest of this valuable native plant?
During the growing season, questions about lawn or turf care are quite common at the Champaign County Extension office.
Native plants offer a whole suite of ecosystems services that are often taken for granted. The faunal associations with our native flora run deep and, through this plant-animal connection, support the ecosystems of the natural world here in central Illinois. Planting native species, even on a small scale, can have a profound impact on the wildlife of Illinois if gardeners and landscapers start to adapt their designs to include more native plants.
The iconic monarch butterfly (Danaus plexippus) has become somewhat of a poster child for the plight that many pollinators face, and for good reason. Monarch populations have experienced drastic declines in recent years for a variety of reasons, some which researchers are still trying to explain. The monarch’s charismatic appearance and large home range, spanning much of the US, has made it familiar to most anyone who has ever caught butterflies as a kid or observed visitors to their flower garden.
Eleven years ago, the US Senate unanimously approved the designation of a week in June as National Pollinator Week, marking a huge step in recognizing both the value of our pollinators and the plight they have faced nationwide. Governors in all 50 states have also recognized the same Pollinator Week in their states. This week (June 18-24) is National Pollinator week, the perfect time to reflect on the value of these hardworking animals.
Visitors to the downtown Champaign area last month may have noticed an odd addition to the One Main Development landscaping. Over the course of May, an increasing number of mysterious white trees appeared out of nowhere. Who placed these ghost trees? Where did they come from?
As agriculture worldwide continues to advance and innovate in an attempt to feed our ever-growing global population, unique and specialized productions systems are popping up all the time. One such system, referred to as aquaponics, includes an interesting mixture of plants and aquatic organisms. Some folks right here on the University of Illinois Campus are currently using this agricultural system to produce locally grown plants and animals for the menu at Bevier Café.
With last week’s Easter snow, it is hard to believe that the frost-free dates for our area are fast approaching. Hopefully April will follow a more March-like tradition of “in like lion and out like a lamb”.
The “frost-free” date for the Champaign area is around April 15th, which is the spring median date for overnight lows above 32⁰, meaning we still have about a 50/50 chance for frost on that date. By April 30th, the chance for frost in our area drops to about 10%, with the latest recorded date for temps below 32⁰ being May 21st.
It’s beginning to be that time of year again, when our vegetables gardens become less productive and most of the season’s bounty has been realized. Before you begin to look toward next year’s plans, why not consider planting something for the winter season? A hard-working cover crop is the perfect selection to fill in your garden and improve soil for next year.
This weekend, I will be traveling to southern Illinois for the experience of a lifetime—a total solar eclipse. The eclipse will occur on Monday, August 21, and will only be viewable in “totality” within a narrow band of approximately 70 miles that extends across the US from Oregon to South Carolina. Unfortunately, in our area we will only be able to view a partial eclipse, which is still fascinating, but does not carry the life-changing impact that many experience from a total eclipse.