Archive for category piedmont gardening
Winter does not appear to be kidding around this year. As soon as 2021 exited with one of the mildest Decembers ever, January ushered in 2022 with some serious arctic air that shows no signs of leaving for the duration of the month.
Our yard is generally 5-10 degrees cooler than locally reported temperatures, because of the slope down to the floodplain and creek that allows cold air to linger. So far this month, we’ve seen one and only one nighttime low above 32 degrees Fahrenheit. Most nighttime temperatures were well below freezing.
This January reminds me of the Januarys of my childhood and adolescence in the Piedmont of North Carolina. It was always miserably cold. We often saw bouts of snow (if we were lucky) and freezing rain (when we weren’t lucky). Native plants and animals remained in deep slumber. Pines and red cedars provided the only green relief in the landscape.
Since Wonder Spouse and I moved to our five acres of green chaos almost 33 years ago, we’ve had a few winters with deep snows, and a few very nasty ice storms, but they were usually followed by a spell of warmth that thawed any hint of frozen ground very quickly. Not this year. The ground in my yard is rock-solid. I feel as if I’m walking across uneven concrete — very cold concrete.
The beaver-built pond and wetland is very icy these days. Over two dozen mallards have been dabbling about in the shallow water all fall and early winter, but now that shallow water is frozen. The creek that supplies the wetland with water is deeper, and the water moves, so it has not frozen over. The mallards noticed, and now spend much of the day swimming up and down the deep part of the creek behind our house. Our wildlife cameras captured many videos of mallard interactions on the creek this past week.
Because this temperature trend is forecast to last until the end of the month, including several more predicted bouts of winter precipitation, I am wondering which plants won’t survive another winter. I grow several non-native so-called tender perennials, two of which are salvias — pineapple sage, and blue Brazilian sage. They have been reliably re-emerging in spring for over a dozen years now. Before that, they were killed by winter’s cold, so to keep them around, I always took cuttings in the fall and rooted/overwintered them in my little greenhouse. However, I stopped doing that some years ago, because it was unnecessary. Now I’m wondering if I’m going to regret that decision.
I usually start spring vegetable seeds in my greenhouse in early February, but the unrelenting cold is making me wonder if I should delay a bit. I’m glad I ordered seeds early. Some of my favorite varieties were hard and/or impossible to find. I’m guessing as the weather warms, vegetable seed options will diminish quickly. Seed catalogs are all online now, folks, and given the weather, electronic catalog browsing might be an excellent way to pass the time.
It has been too cold to risk lifting the row covers over my winter broccoli and lettuces, but I’m pretty sure that when I do I will find green mush. Row covers can protect crops down to about 25 degrees, especially if that temperature only lasts a few hours. Our nighttime temperatures have been in the teens every night all night. Gardeners are gamblers. This winter season, I harvested some wonderful veggies in December, which makes the January losses easier to tolerate.
I think the mallards have the right idea. When winter gives you a frozen pond, go dabble in a creek until the weather thaws. When winter gives me frozen ground, I stay cozy in my house, dabbling through catalogs and a pile of books that need reading, dreaming of the new season of flowers and fruits that will likely arrive before my winter napping is done.
I spent an hour or so yesterday morning walking around our five acres with my camera to record the state of things as this year draws to a close. The weather here in central North Carolina has been alarmingly warm and we are struggling with moderate drought. However, a bit of rain fell the previous day, and gloom persisted yesterday as rain fell to our south. Winter, the forecasters say, will return on the second day of the new year, shocking plants, animals, and humans alike, I imagine.
The warm spell has been a gift to our winter vegetable garden. In past years, I have kept them tented all winter beneath row covers to protect them from freezing temperatures. Severe cold will turn the greens and broccoli to mush, but beneath row covers, lows into the mid-20s for a few hours do the veggies no lasting harm. This latest warm spell has been so prolonged that I’ve been able to remove the row covers to give the veggies access to full sun. I even gave them all a dose of fish emulsion/seaweed mix this week. Winter fertilizing is not something I am usually able to manage, because I don’t want to expose them to prolonged cold.
We harvested several heads of broccoli — I’m trying Emerald Crown this year — which we will be enjoying with tonight’s dinner. Broccoli doesn’t do well here as a spring crop anymore. The days warm up too quickly. But winter’s chill sweetens them as they grow beneath their row covers. The row covers also protect them from cabbage moth caterpillar damage without the need for any pest control substances.
The greens are all doing great. I’m averaging one salad a week by picking individual leaves. Beet greens provide a bit of zip to the mix of lettuces and spinach. The warm spell accelerated the growth in this bed visibly. I may get two salads out of it next week.
Winter-blooming flowers — all but one non-native — are opening. Pink blooms of one flowering apricot were scenting the air yesterday. Today, the other one also began blooming. I look forward to the perfume from these flowers every year.
January jasmine, which has no fragrance, is also beginning to open its bright yellow flowers that are often mistaken for forsythia. When I leaned in to photograph this flower, I was surprised to find it occupied.
Today, I noticed that my non-native Persian ironwood is beginning to bloom. This tree is in the witch hazel family, and the flowers are not showy, but I have observed honey bees visiting them.
My native witch hazel ‘Amethyst‘ has already begun to bloom. Typically, it waits until middle-to-late January. This shrub insists on holding on to its leaves, but it’s still quite lovely in bloom — and its fresh scent never fails to lift my spirits.
Most of the berry-producing shrubs in our yard have long been picked clean, but the red berries of native deciduous holly and the deep purple berries of native greenbriar vines were still visible when I walked around yesterday.
A few shrubs are still holding on to their autumn-colored leaves, including my native oakleaf hydrangeas. I grow the smaller form, ‘Pee Wee,’ and I recently added a full-sized one, cultivar ‘Alice.’
Dried seed heads of cardinal flower and goldenrod also caught my eye, as did an ever-increasing abundance of bald cypress knees emerging from the muck where three trees I planted three decades ago have now attained heights between 40-50 feet.
Bared tree branches reveal their complex beauty during this leafless season. I was especially enthralled yesterday by a young winged elm. Its corky extrusions along its trunk and every branch made its silhouette quite striking.
Even during this time of moderate drought, the new channel that cuts through what was for 25 years dry, flat floodplain merrily chuckles its way toward a growing wetland pond, home to at least two dozen ducks. I have accepted the fact that this part of the floodplain is now a wetland. And, I must admit, the permanent streamlet that now traverses that area adds an air of tranquility to the landscape.
Never have I been more grateful for my lifelong passion for gardening and the natural world. I am certain the dirt perpetually beneath my fingernails is largely responsible for the retention of my sanity during these challenging times. I know that you, my readers, understand this. Here’s to a new year filled with fruits, vegetables, flowers, pollinators, and ever-dirty fingernails.
Even though I heard them and often saw their tracks, I did not have a good idea about the numbers and diversity of native wildlife that regularly use the creek we live beside as a busy highway until we invested in some wildlife video cameras. In a typical Piedmont suburb, you may not see all of these species — although it is not impossible. But if you live beside or near water, especially a permanent stream, it is likely that you are sharing the area with a diverse array of native animals. [Note: You can click on any photo to view a larger image.]
Today I am sharing a few stills, in chronological order, taken from videos captured over the last two months. Personally, I never tire of watching my wildlife neighbors as they seek and catch food, argue over territory, or merely pass by on their way to somewhere else. The cameras capture Great Blue Herons fairly often. We’ve even captured some interesting moonlight interactions between them and beavers. I like the recent shot above of this majestic bird with voice croakier than most frogs catching a fish on a chilly morning in early November.
We hadn’t seen foxes since last spring until they began showing up again on the cameras in November. A daylight video of one slurping up creek water during the drought confirms we have gray foxes. Their gait is a subtle prance, and their tails are spectacular.
We usually catch bobcats in the spring and fall, but these solitary creatures were always alone — until the camera caught this pair. We hypothesize they may be litter-mates still hanging around together. You can’t see the temperature reading on this one; it was 35 degrees.
Recent forest destruction to make way for yet more suburbs has pushed more deer our way than in recent years, including at least five bucks of varying sizes. The young buck in this capture completely ignored the pair of raccoons across the creek.
Opossums are usually a blur on the video captures, putting to rest the notion that these critters are sluggish. However, this night was so warm that the opossum here was taking its time as it foraged beside the creek.
We are lucky to see and hear Pileated Woodpeckers often, thanks to the dead and dying trees in the beaver-built wetland across from us. However, we had never seen one of these crow-sized birds foraging on the ground until a camera captured this one in action.
The cameras capture raccoons year-round. This recent shot shows a damp one that had just swum across the creek. We often catch them swimming, regardless of temperature. They seem to prefer to use the shortest route between points to get where they’re going, even if that means a dip in cold creek water.
Especially in spring and throughout fall and winter, coyotes patrol the creek nightly. We’ve never seen more than two at once on the cameras, but we hear more than that howling nearby, especially when it is cold.
These last two shots were taken within minutes of each other last week on a very cold night. All the creatures were active, probably because it was so cold and the moon was bright. Despite an array of predators, this camera often captures cottontail rabbits casually foraging out in the open. We don’t know if they are very lucky bunnies, or if there are just so many of them that all can’t be eaten. We were surprised by the brazenness of this bunny that is almost stepped on by a big buck.
Given this final photo taken just minutes later, we think the bunny somehow knew that this buck was not the least bit interested in cottontails. Instead, he was defending his turf against another big buck, as evidenced by this antler-locked tussle caught on video. We expect to start finding discarded antlers soon, given the constant presence of the bucks this year.
The forest around the creek I live beside is the only remaining high-quality wildlife corridor remaining on my road. All the native animals are being squeezed into this narrow corridor which leads to the Haw River nearby. My prayer for this new year is that somehow a way is found to persuade the long-time owners of the forest around this creek to put the land into a conservation easement. This would protect the land from the bulldozers forever. It would create a refuge for all the creatures in my area, and provide a safe way for them to travel to other bits of remaining forested land. If I were wealthy, I’d try to buy out the landowners myself. Alas, that’s not an option.
Barring a monetary miracle, all I can do is what I’ve been doing. I’ll keep adding native food and shelter plants to my side of this critical wildlife corridor in the hopes that the creatures can manage to survive despite their displacement by now nearly ubiquitous suburbs, all of which are erased of almost all native vegetation before humans move in.
Today’s Christmas Eve sunrise was spectacular. Fleeting, as always, but well worth braving the chilly air as nuthatches chittered, woodpeckers squawked, and mallards in the adjacent wetland greeted the light with argumentative-sounding quacks.
Winter is the only season that permits sunrises to penetrate the tall trees that I am blessed to share my home with, so I cherish every one I can. I don’t even want to guess how many photos of winter sunrises crowd my files, and I don’t care.
Every sunrise is slightly different, but all evoke the same emotions in me:
- joy at the beauty of creation,
- love for the creatures greeting the morning all around me as I stand on my deck snapping photos,
- and a tinge of melancholy prompted by the fleeting nature of these sunrise moments.
For all my readers who celebrate Christmas, I wish you a very merry one. May you be surrounded by joy and love. May your days be merry and bright. And may all your sunrises be glorious.
As I pondered our seasonal turn to winter, this fell out of my fingers. Happy Solstice to all.
Light a candle against the darkness.
Light a fire, watch it burn.
Beneath the warmth of extra blankets,
dream deeply as the seasons turn.
Feel the light always within you,
your connection to the divine.
Like roots beneath a forest,
we are all intertwined.
Plant dream seeds in the moonlight.
Your heart knows they will grow.
A spring garden of beauty and love awaits you
when it is time to reap what we sow.
I learned a new ecological term this week. Johnny Randall, the Director of Conservation Programs at the NC Botanical Garden, mentioned it while we were discussing material for an article we are collaborating on for the spring issue of their magazine, Conservation Gardener. Although the term was new to me, the meaning behind it was not unfamiliar.
Three researchers from the University of Tartu in Estonia developed the concept of dark diversity in a paper they published in 2011. Their term was chosen to parallel the notion of dark matter in astrophysics. As with dark matter, dark diversity can be inferred from data, but it cannot be seen or directly measured.
Conservation ecologists, especially those attempting to restore or sustain ecosystems, are using the idea of dark diversity to help them assess the health of the system they are studying. Imagine a healthy ecosystem, one with all its components, where every plant, fungus, insect, bird, etc. that should live there actually does live there. This is almost never true anymore. Humans have fragmented and/or destroyed so much now that nearly every bit of forest, field, stream, coral reef, etc. is missing species that were, until fairly recently, components of those ecosystems.
Thus, these days when conservation ecologists attempt to preserve/restore special examples of ecosystems, often those containing rare plants, they not only must identify the species present on the site; they must also attempt to figure out what species are missing. Species still present can be seen and counted, their viability assessed; this is visible diversity. The absent species, the ones that should be there but aren’t define dark diversity.
I’m oversimplifying the concept a bit, but, basically, ecologists estimate dark diversity by looking at species diversity in the region in which their study site is located. If, for example, a section of forest being restored was missing wood thrushes (one of my favorite summer visitors of our forests), but those birds were known to live in patches of forest in the region, wood thrushes would be identified as part of the dark diversity of the study site – a species that should be there, based on its presence in the region, but is absent.
As I can best understand the concept, by measuring the amount of dark diversity, ecologists can better guess how difficult it would be to restore a given site to full diversity – to bring back all the missing species that should be living on a site but aren’t.
Dark Diversity on Our Five Acres
When Johnny Randall mentioned the concept of dark diversity, it immediately resonated with me, because Wonder Spouse and I have been playing with the dark, as it were, on our five acres for over three decades now. When I first saw this land on a cold January day almost 33 years ago, it was an ecosystem with substantial dark diversity. The previous owner had eliminated almost all the native grasses, wildflowers, shrubs, and understory trees, leaving only towering canopy-level trees and a lawn full of non-native grasses. I could hear birds, but I rarely saw them in our yard. There was nothing for them to eat near ground level, and no good nesting sites.
However, the floodplain forest on the other side of the creek teemed with ferns, wildflowers, and a healthy shrub layer. Bird song echoed across our empty yard from that area. I knew that all of those species should also be living on our side of the creek. Those species not present on our land but living nearby were dark diversity – the missing pieces. I wanted to bring them back.
Through trial and error, luck, and hard work, we have rebuilt much of the species diversity that lived on our property before it was damaged by the previous owner. Fruit-bearing shrubs provide food for an array of species. Dense plantings of shrubs, grasses, ferns, and wildflowers provide food and shelter for insects, reptiles, amphibians, birds, and an array of mammals.
I am certain that our amateur habitat restoration efforts would not pass muster with the professionals, but I think our results speak for themselves. What once was unseen – dark – is now visible. The species that were nearby but absent on our land have returned. I do not have adequate words to describe how deeply gratifying it has been to bring the dark into light, to bring the missing species home.
Contemplating the dark seems an entirely appropriate occupation as we rapidly approach the darkest night – winter solstice. A wise person recently told me that, when navigating dark times, it is important to trust the invisible. It seems wise folks from astrophysicists to ecologists follow this guidance. Darkness – what we cannot see with our eyes – teems with life, with knowledge. It may well be true that we can learn more from the unseen than from our visible world.
Where is your heart? I ask, because I’ve been thinking about a familiar cliché – home is where the heart is. I’ve been asking myself that question as I ponder what I am thankful for during this season of blessing-counting. Where is home for me? Where is my heart?
My instant answer is that my home is, above all else, my soul mate, my Wonder Spouse. With him, I am always warm and safe and entirely loved. He is a blessing I try never to take for granted.
Home is also this five acres of land Wonder Spouse and I have nurtured together for over three decades. To the real estate industry and government, we are owners of this piece of Piedmont paradise, but we know better. We are collaborators with all that lived here before us and those who have arrived since. We know the trees do not belong to us, though we do our best to care for them, and always appreciate them. We know the birds, frogs, foxes, and turtles who dwell among us do not belong to us, but we welcome their presence and try to encourage it by creating habitats that are heart homes for them.
Wonder Spouse and I have worked hard to make our five acres healthier and more diverse than when we first arrived. Stripped gradually of human artifices such as lawns and non-native plants that feed no one, this Piedmont patch grows more alive with every passing season. Truly, this land is our heart, our home, our family, and we feel deeply blessed to have found it, joyfully embracing our work to return it to vibrant native diversity.
I know how blessed we are. Many humans around the globe have no home. They are hungry, often cold and afraid. To my mind, the inequities among humans reflect attitudes about all our relationships, beginning with how we treat Mother Earth and all her non-human inhabitants. Perhaps the perpetrators of these inequities rationalize their behavior by believing they are doing it to Someone Else.
However, I believe that anyone with open eyes can see the interrelatedness of everything, from the air we breathe and the water we drink to the food we eat. Equally accessible sustainable ecosystems are necessary for all our families to thrive.
On this American day of thanksgiving when you give thanks for your family gathered round tables laden with abundance, for their health, for whatever other blessings you acknowledge, please consider also giving thanks for the fact that none of those blessings is possible without the blue-green planet that nurtures everything, home to us all. Give thanks for Mother Earth, and consider making a promise with your family to do more for her sustainable health. It is the only way we may be assured of Thanksgivings for many generations to come.
As promised in my previous post, this is my summary of the presentations given on the second day of the virtual conference of the NC Invasive Plant Council this past week. I apologize for the length. I tried to be as succinct as possible.
That was the title of the talk, just the generic name of the herbicide better known to many by the commercial product with the name that rhymes with groundup. This presentation was given by a professor from NC State University. Although it is much more than a land-grant institution concerned with agriculture and engineering today, those areas were its original focus, and are still very important. Much academic effort remains focused on supporting what I think of as the traditional agriculture and horticulture industries. I assume it is that focus that explains the approach taken by this speaker. I feel obliged to go into some detail about this presentation. I think my reasons will become evident quickly.
From my perspective as a well-educated woman with a substantial knowledge of ecology and gardening, his talk began inauspiciously. His opening slide portrayed a woman dressed in the 1950’s cliché style of a “typical housewife” – perfect dress, high heels, permed hair, and make-up. She was standing on an immaculate green lawn in front of a house. Behind her, she pulled a large clunky-looking machine that was spraying what I assume was supposed to be an herbicide mixture onto her lawn, all while smiling prettily for the camera.
I pondered what message the speaker intended to convey with this image. Was he harkening back to “the good old days” when women knew their place and happily spread poisons without worrying about safety protocols? Did he think he was being funny? I tried to continue listening with an open mind, but the talk went downhill from there for me.
This professor was not the most coherent of speakers, but I think his primary point was that anyone worried about glyphosate is misinformed and should shut up and leave the poisons to the “experts.” He showed a few graphs demonstrating how much less toxic glyphosate is than some of the herbicides farmers used in the recent past. That’s true. Glyphosate doesn’t persist in the environment as long as those more toxic herbicides, and it is probably less dangerous to humans.
His next words raised my hackles. He showed the label from the Non-GMO Project that appears on food products that have been certified by that organization. At the same time, he said, “Not to be sexist or anything, but women buy most of the food in the house.” I braced myself. As best as I could make out, his point was that women are so stupid that we think the Non-GMO Project label means the food was produced without the use of herbicides and that makes the food safer, which is why we buy it. I can’t speak for women everywhere, but I can tell you that I – a woman for some decades now – know the Non-GMO Project label certifies that the food was not created by bioengineering methods that genetically modified it.
The speaker never really articulated his objection to the Non-GMO label, but I can guess what it might be. Traditional agricultural operations that produce hundreds of acres of soybeans, corn, and other staple crops have been moving substantially toward the use of genetically modified seeds that contain genes making the food crops resistant to the application of glyphosate. Now, instead of needing to till crop rows to control weeds, farmers merely spray their entire fields with glyphosate, thus killing all the weeds while the food crop survives.
I imagine that my readers can come up with all kinds of reasons for being uncomfortable with the idea that food they might eat is grown this way. Personally, I’ve been grateful for the Non-GMO product certification label since it began appearing. And I’ve always known that the label does not necessarily imply that the food was grown organically and/or without the use of herbicides/pesticides. It merely indicates the food was not bioengineered so that poisons could kill weeds in the field without killing the crop.
After insulting female food-buyers everywhere for being stupid enough to conflate non-GMO foods with those grown organically, the speaker spoke at length about the fact that no government agency has declared that glyphosate causes cancer in humans or other mammals. He made a point of stating it that way for good reason. Scientists have been studying the effects of glyphosate on non-mammals for quite some time. Here are a few relevant journal articles:
- Glyphosate inhibits melanization and increases susceptibility to infection in insects
- Common weed killer – believed harmless to animals – may be harming bees worldwide: Glyphosate appears to alter the bacteria in the insect’s guts, making them more vulnerable to infection
- Effects of the Herbicide Glyphosate on Honey Bee Sensory and Cognitive Abilities: Individual Impairments with Implications for the Hive
- Amphibians Are Not Ready for Roundup
- Chronic exposure to a glyphosate-based herbicide makes toad larvae more toxic
For those who think I’m cherry-picking journal articles, here’s one for the pro-glyphosate team:
I am not an expert on herbicides, but it appears to me that the most generous statement one can make is that, at best, data are mixed on the impacts of glyphosate on non-mammalian wildlife. I suspect that, as the last article above states, when used correctly at appropriate concentrations and appropriate application techniques, glyphosate is a useful tool in the battle to control non-native invasive plants. If the presenter of this talk had said this, instead of “mansplaining” to women he deems too stupid to understand, I would not be writing all this. However, because this professor’s job is to support the agriculture industry’s use of glyphosate, I think he chose to obfuscate with a tirade about non-GMO labeling on food products. Moving on…
Response of Invasive Plants to Fire at Picture Creek Diabase Barrens
After the previous talk, it was a great relief to me when this presenter began. A plant ecologist, she is the Program Manager for the North Carolina Department of Agriculture’s Plant Conservation Program, a group whose mission is to protect rare plants in North Carolina.
Picture Creek Diabase Barrens is a site containing a remnant community of Piedmont prairie plants. Hanging on by the merest of threads, it survived because it grows beneath high-tension powerlines, which means the power company has been keeping that area free of forest encroachment for decades. Until fairly recent times, the trees were removed manually, which is probably why the rare plants survived. These days, of course, utility companies prefer to spray herbicides on such lines. In my area, they do it using helicopters. Many areas deploy teams of workers with backpacks full of herbicide to kill everything growing within the utility right-of-way.
Conservation groups, including the NC Botanical Garden and the Friends of Plant Conservation have been helping to restore this particular rare ecosystem. In addition to tackling the non-native invasive plants encroaching on the area, they’ve collected seed from some of the rare plants, which they grew out and then planted on the site. Controlled burns are very effective at controlling unwelcome plant species in Piedmont prairies. It was the way they were maintained by Native Americans before European colonists arrived. Burns don’t always control all unwanted species. Careful applications of correct concentrations of glyphosate are also used to battle invasive species on this site. The presenter emphasized the need for careful applications. Her staff is trained to recognize desirable and undesirable species. It is slow, painstaking work to move through this fragile plant community spraying herbicide only on unwelcome species.
The speaker emphasized this because of unhappy experiences with crews from the power company that are paid to spray herbicides on the powerline right-of-way. They are not trained to recognize one plant from another. They douse anything green with poison, and they move quickly, which may explain how they missed the signs marking this protected rare plant community as a no-spray zone. The speaker told us it has taken years of hard work to persuade the power company to allow conservation experts to manage rare plants beneath powerlines. After a recent incident in which power company contractors missed the signs and sprayed herbicide on the protected rare plants in this location, the speaker told us all parties sat down together again to discuss how they might prevent this from happening in the future. The good news is that they all agreed to meet together once per year for the indefinite future to ensure that all parties are always current on agreed-upon procedures, thereby decreasing the likelihood of future communication lapses.
Invasive Plants in Glades
The man who presented this talk is a Public Lands Field Biologist for MountainTrue, a conservation organization that “champions resilient forests, clean waters, and healthy communities in the Southern Blue Ridge.” I would describe his interesting slide presentation as, at best, tangentially related to the subject of non-native invasive plants. He spent almost all of his time describing the interesting, often rare plants that occur in glade plant communities. His definition of what constituted a glade was a tad fuzzy to me, but suffice it to say these communities grow on the sides of mountains on relatively steep slopes. He mostly showed us many photos of interesting plants. At the end of his talk, he mentioned the non-native invasive plants that he usually sees encroaching on glade communities. I don’t remember if he talked about how he controlled them.
Emerald Ash Borer and Other Invasive Pests
As far as I’m concerned, this was the most depressing presentation of the conference. The speaker, a Ph.D. entomologist for a local big tree-care company, described the non-native invasive insect species that he believes will impact our local ecosystems most significantly. I’ve written several times about one of them. I may have mentioned the second invader at least once, and I don’t think I’ve described the other one before.
I’ve written about this phenomenally destructive insect several times in this blog. Enter “Emerald Ash Borer” in the search box to find those entries. I also wrote an article about it for the magazine of the NC Botanical Garden.
This insect from Asia is systematically killing every ash tree in North America. In northern states like Michigan, the only ash trees still alive are the ones treated every other year with systemic insecticide. The insecticide is injected into the tree, the poison permeates the entire tree, and any insect that takes a bite of a treated tree dies. Federal agencies are experimentally releasing four different species of parasitic wasps from Asia that target varying life cycle stages of EAB. The speaker said that at least one of those wasp species was found the following year, meaning it successfully reproduced by feeding EABs to its larvae. This potentially good news is not great news. First, these releases are still experimental. Regular folks and even tree companies, such as this speaker’s employer, do not have access to these wasps. Also, the speaker noted, no one believes these wasps can eradicate EAB. At best, if the wasps successfully multiply, it might be possible – maybe – for the wasp and EAB populations to reach a sort of truce that might allow some ash trees to survive. Maybe.
A lot of us were hoping, I think, that the wave of marauding EABs would pass through an area, then leave after killing all the ash trees. Alas, according to this speaker, that is not what is happening. Up north, where EAB has been present for 20 years, he saw instances in which a homeowner decided it was safe to stop treating the ash tree on their property, because all untreated ash trees were dead. In such cases, EAB infestations killed such trees five years after insecticide treatments were stopped.
The speaker told us that it is hard to tell when EABs have infested an ash tree, because they begin by boring into branches at the top of the tree, where it is hard to see the dieback. By the time most folks notice their ash trees are unwell, EAB infestation is too far along for systemic insecticide treatments to be effective. He said that if more than 30% of the branches in the canopy are dead, the tree is doomed. He also said that he has seen ash saplings with trunks the diameter of his thumb infested with EAB, which is how the invader persists in an area indefinitely. The species also enjoys dining on our native fringe trees. Barring a miracle, I think it is safe to assume North American ash forests are doomed.
He also mentioned one other fact about dead ash trees that I did not know. When dead, this species becomes dangerously brittle very quickly. He told us that any “tree expert” who claims he can climb your dead ash tree to cut it down from the top is risking his life. No sane arborist, he said, will ever climb a dead ash tree, because it can break and send him tumbling in an instant. Either the tree must be felled in its entirety by cutting it at its base, or a bucket truck must be used to safely access the top of the tree to remove branches.
When the non-native Redbay Ambrosia Beetle lays its eggs inside plants in the laurel family (Lauraceae), it also injects a fungus, called Laurel Wilt, that kills the tree within months. Redbay (Persea borbonia) is a dominant member of plant communities growing in the southeastern coastal plain. In North Carolina, when you drive past areas where this species once dominated, you see miles and miles of dead trees.
Redbay Ambrosia beetles also kill spicebushes (Lindera spp.) and sassafras trees in the Southeastern US. Somehow the beetle has made it to California, where it is posing a grave threat to avocado groves and native California bay laurel trees. The speaker told us that female Redbay Ambrosia beetles are parthenogenic, which means they lay fertile eggs without the need for insemination by a male. One female beetle, the speaker told us, can kill a tree simply by laying her eggs in it.
The speaker joked about the beetle as a grave threat to guacamole lovers everywhere. I’m more worried about Spicebush and Palamedes Swallowtail butterflies. Their caterpillars dine exclusively on plants in the Lauraceae family. And think of the native fruit-eating birds that rely on the fruits of redbay, spicebush, and sassafras. What will they eat when all these species are dead? He also mentioned that the latest data show this insect has been detected in a county less than a hundred miles from mine. It is moving inland from the coast, no doubt on the lookout for spicebushes and sassafras trees.
I warned you this speaker’s talk depressed me.
Study the pictures in the link above to learn what this insect looks like. If you see it, report it to your local extension agent. The speaker said this insect is not quite in NC yet, but is expected any time now. This is not good news.
Larvae of this insect happily eat and damage many different species, including fruit trees. According to the expert, this insect may not kill trees outright, merely damage them. Being from Asia, they evolved with Tree of Heaven (Ailanthus altissima). This Asian invasive tree has invaded North Carolina forests and roadsides and is a favorite food of Spotted Lanternfly – just another example of why non-native invasive plants are not our friends.
The speaker showed a short, truly creepy video of thousands of larvae of Spotted Lanternfly swarming up the trunk of a fruit tree, covering every inch of it. It reminded me of videos of fire ants swarming over an animal. Scary stuff.
The entomologist said the larvae damage but do not usually outright kill trees. However, they do kill vines, and the larvae love to eat vines, especially grape vines. The speaker says he’s even seen this insect kill poison ivy vines. I wanted to ask him if he knew whether it would eat Asian wisteria or kudzu – two Asian invasive vines I’d love to see disappear, but the virtual format of the meeting and a tight timeframe did not give me that opportunity.
I am assuming that the insects kill vines, because vines are smaller. The larvae literally drain them dry. He emphasized that the wine industry is terrified of this insect, because of its fondness for grape vines. He said that Spotted Lanternfly has been sighted in western Virginia along its border with NC, just above NC’s Yadkin river basin – a region acclaimed for its wineries.
Breaking News Regarding NC’s Spotted Lanternfly Situation!
A Master Gardener friend, just pointed me to this article. The NC Dept. of Agriculture and Consumer Services Plant Industry Division has recruited two canines to aid in detecting this insect, which the experts suspect may have already begun infiltrating the state. Here’s hoping their excellent noses can find early infestations that their human coworkers can eliminate!
I hope my posts about this conference have been helpful. When the NC-IPC makes videos of the presentations available on their web site, I’ll note that in this blog, so that you can view them yourself and draw your own conclusions.
This past week, I attended the annual conference of the North Carolina Invasive Plant Council (NC-IPC). The continuing pandemic necessitated that the conference was virtual. The up side of that was that I didn’t have to travel or pay anything to attend. The down side was that I was thoroughly depressed by most of what I heard from the experts. This post summarizes the presentations given on the first day of the conference.
NOTE: To offer a little visual relief, I’m interspersing recent photos taken in my yard. They have nothing to do with the subject, except to serve as reminders of the beauty and diversity of native Southeastern Piedmont flora and fauna.
Most of the people who attend this conference about non-native invasive plants are professionals who deal with these plants daily as part of their jobs. Many of them work for conservation organizations that are trying to preserve special ecosystems and/or rare/endangered plants in preserves scattered across North Carolina. Some attendees are university students and professors who study related subjects, such as the impacts of non-native invasive plants on our native ecosystems. Some are associated with botanical gardens and plant nurseries. Some run small companies that specialize in invasive plant removal and habitat restoration. And some are just plain folks like me, who like to keep abreast of what invaders the professionals are most worried about and the methods they are using to combat non-native invasive plants.
Before attending the conference, I assumed that the NC-IPC was still a non-profit organization, so I sent them $20 to re-join the group. However, after the conference, I got a note from an officer in the group who thanked me for my donation and warned me it isn’t tax-deductible, because the group lost its non-profit status. He did not elaborate, but I’m guessing that this all-volunteer organization fell into disarray during the pandemic, and necessary paperwork wasn’t filed. I’m sure they aren’t the only organization still struggling with such issues. The NC-IPC officer did note that the group is working to regain its non-profit status. I wish them well.
Attendees were assured that all virtual presentations were recorded and will be made available to us. I hope so. I missed bits of some of them, and others showed relevant URLs in slides that I didn’t have time to jot down. I’m hoping they’ll simply put them all up on their web site, so that everyone can benefit from the presentations.
While we wait for the recordings to appear, here’s my summary of what I learned on the first day of the conference. I apologize to presenters in advance for any inaccuracies in my summaries. It is hard to take notes, watch slides, and investigate URLs simultaneously.
Exotic Invasive Seed Bank
The professor from UNC-Asheville who gave this talk demonstrated some out-of-the-box thinking that I appreciated. She spoke about Living Web Farms, an organization in three locations in the Asheville area. She described the group as experts on the cutting edge of all aspects of organic, sustainable gardening/living, and she mentioned a product they use, called EM-1, which is a microbial inoculant. As best as I can tell, EM-1 is a concentrated soup of fungi and bacteria that, when diluted and applied to soils, stimulates impressive vigor in plants. The professor said the presentation she heard about it made claims about EM-1 that included elimination of body odor, among other things. She did not provide details.
However, she did apply EM-1 to the soil in her established vegetable garden and got what she considered to be very beneficial results – improved vigor, more fruit production, disease resistance – everything a gardener wants. It also supposedly provides improved seed germination. This clever professor decided to test that last claim by applying EM-1 to test beds of seeds of plants, such as alfalfa. In some plots, she added a bit of sugar or molasses to the mix, because, she said, sugar often improves seed germination. This was news to me.
She discovered that EM-1 most definitely improved germination rates of seeds in her test plots. She wondered what would happen if she added a higher-than-recommended concentration to seed beds. The alfalfa germinated at impressive rates, but the radicle – the root tip – died, which meant the entire plant died. This led the professor to wonder if applying this higher concentration of EM-1 to beds full of seeds of non-native invasive plants would cause these species to also germinate and die. I won’t bore you with the details, but it appeared likely that she did succeed in encouraging germination of weed seeds at high rates, and those seedlings then died.
Why does this matter to those of us attempting to control invasive plants? Because seeds of plants like Japanese stiltgrass can remain viable in the soil for 7-10 years. However, if one had a way to encourage all those seeds to germinate and die simultaneously, it might be possible to exhaust their seed banks (seeds lurking in soil), thereby reducing populations of these pernicious species.
I think this is a gosh darn clever notion. I especially like it because no poisons of any kind were necessary. I hope she pursues and refines this research so that “regular folks” can try this approach. Meanwhile, I have ordered a bottle of EM-1 to test out on my vegetable garden. I’ll let you know what happens.
Bird Friendly Landscaping
The woman who spoke next is the current president of my local Audubon chapter. This local group has been advocating successfully for restoring native plants to landscapes in order to improve habitat for native wildlife, especially birds. The group’s very professional Web site is jam-packed with wonderful information on this subject. Readers interested in learning more should start here.
Using Imazamox to Control Japanese Knotweed
I confess I sort of snoozed through this man’s talk. If the subject is of interest to you, check the NC-IPC Web site for videos of the conference when they appear.
The Skewed Logic of Invasive Defenders
The man who gave this talk is an active conservationist who has founded local groups to restore/preserve native ecosystems in areas where he has lived. He is a very thoughtful, articulate guy, and feels obliged to argue with folks who write/speak in defense of non-native invasive species. Whole books have been written about this. These invader-supporters advocate a live-and-let-live approach, saying non-native invasive species have a right to be here even if that means entire native ecosystems perish as a consequence.
The speaker’s presentation described the most common arguments invasive-defenders make, and then identified the fallacies in those arguments. He also recounted how he has debated – in writing and in person – with some of these invasive-lovers with mixed results. In Nature’s Best Hope by Douglas Tallamy, one of the appendixes in the book offers counter-arguments to those who advocate on behalf of non-native invasive species. It saddens me that this is necessary.
NC-IPC’s Ficaria verna Program (as a model for others)
The common name for this invasive plant is Fig Buttercup. It is a relatively recent invader to our area, notorious for overwhelming native wetland habitats. It has a pretty flower, which is how it got here. The presenter described how the NC-IPC has allotted money for an education campaign about this plant in the Research Triangle area of North Carolina, where the invader is beginning to get a foothold. For those of you who live in this area, check out the application (Find Fig Buttercup Near You!) they’ve built to help you figure out how close this invader is to your property. This link from the Duke Forest web site describes this invader and why it is a problem. Please keep an eye out for this invader wherever you live. It is tricky to eradicate.
Invasive Plants in Urban Forests: Effects on Forest Structure and Arthropod Communities
The woman who gave this presentation described her Ph.D. thesis, as indicated in the title. I’ve found that newly minted Ph.D. earners are often unable to summarize their work. After all, they’ve been immersed in the minutia of their subject matter for years. They probably dream about it. It is thus understandable that this young woman began by describing in exhaustive detail the methodology she employed in her study. Forgive me, but it was lunch time by then and I was hungry. It was the last presentation for the day, so I left the meeting to eat lunch. I figure I’ll zip through the video to her conclusions when that video becomes available. I’ll be surprised if she did not find a reduction in overall arthropod species, and probably a change in species proportions, because that’s what usually happens when invasive species disrupt native ecosystems. But I’ll check when the video becomes available.
Thus ended the first day of presentations. I found the presentations during the second day to be, in order of presentation, really annoying, interesting and inspiring, interesting, and very depressing. I offer details in the blog post that follows this one. I’ll post it tomorrow.
All gardeners know that fall is for planting. It also marks a rise in wonderful presentations on gardening-related subjects. Case in point: the amazing Debbie Roos, one of the agricultural extension agents for Chatham County, NC, will give what promises to be a great webinar from 6:00-8:00 p.m. on November 10.
To read more about Creating Wildlife Habitat with Native Plants and to register to virtually attend, visit the link. You will learn much, I promise!
For those of you deeply interested in invasive plants, the expert members of the NC Invasive Plants Council will be virtually gathering for two half-days of presentations on November 9-10. Presentations can get a tad technical for the layperson, but you will learn about control methods, which species the experts are most worried about, and other useful information.
You can attend for free, but please consider joining the group to help fund their efforts. To see the agenda and register, go here.