Link for My Latest Published Article on “Invasive" Plants

When people like nonnative plants, they don’t complain about how far and wide they spread. At a facility near the University of Virginia in Charlottesville, alien crocuses have spread throughout the lawn over the course of decades. Would anyone ever refer to these flowers as “invasive”? Probably not, because they create such a lovely sight. 

ALL TEXT AND PHOTOS  © Marlene A. Condon

 

On July 12, 2024, The Daily Progress (the daily newspaper of Charlottesville, VA) published my article regarding the value to wildlife of so-called invasive species, such as the Mimosa-tree (Albizia julibrissin). You can find it at the link below, where half a dozen photos make clear the reason for the spread of naturalized plants (now usually referred to as “invasive”) as well as provide examples of some of the wildlife that makes extensive use of the alien Mimosa.

  

https://dailyprogress.com/opinion/column/marlene-a-condon-theyre-not-invasive-species-theyre-naturalized/article_d65069bc-4031-11ef-b27f-3774d5c1dde3.html

 

If you can’t access my article at this site, I am reproducing it below for your convenience.

 

Sincerely,

Marlene

Exotic Mimosa-tree Provides Food and Beauty

 

You’ve probably noticed the tropical-looking trees with gorgeous pink puffs of flowers that are currently blooming around the area. Known as the Silktree (or Silk Tree), Mimosa-tree, or just Mimosa (Albizia julibrissin), it presents a sight that most folks enjoy viewing, but others do not because they consider this nonnative tree “invasive”. But is it? Not at all; it’s “naturalized”.

Untended areas, such as the one in this photo, serve as important food sources for our native wildlife trying to eke out a living in urban areas. Here, a blooming Mimosa-tree helps to ameliorate the pollinator food-desert resulting from the nearby native trees having long since flowered. 

The lovely blooms and fern-like leaves of the tropical-looking Mimosa-tree provide landscape color at a time of year when it’s hard to find a native tree blooming.

If you’re a gardener who has lived long enough, you’ll recall that decades ago, plants that became established and survived on their own, able to spread in a region where they were not indigenous, were considered wonderful additions to the landscape. You got more plants for free and more beauty to savor in your surroundings.

 

Even today, some plant catalogs tout naturalizing: “For a carefree, colourful display year after year, let your bulbs go wild! Flowering bulbs will keep your garden ablaze with colour when other plants are just emerging or have faded. Naturalizing is the process of imitating nature with bulb plantings.”

 

https://www.brecks.com/how_to_landscaping_with_bulbs_naturalizing

 

Note the final sentence that imparts the wisdom that “naturalizing is the process of imitating nature”. This statement reveals recognition of the fact that plants spread when conditions suit them in the natural world. In other words, what folks today refer to as invasiveness is a misreading of a natural process that is neither mysterious nor mystical, nor hard to understand.

 

Old books don’t complain about “invasiveness”; to the contrary, they treat naturalization as the normal—and often desired—outcome it is for some alien-plant species.

 

My 1988 Peterson Field Guide to Trees tells the reader that Mimosa is “[n]ative to S[outh] Asia but widely planted and naturalized in the eastern U.S.” My 1983 Illustrated Book of Trees informs us that “[the Silktree] has become extensively naturalized from Virginia southward and often grows by the wayside.”

 

The latter book points out that Mimosa “is able to thrive on even the poorer soils”. My 1980 book, The Audubon Society Field Guide to North American Trees, concurs. It tells us this tree occurs in “[o]pen areas including wasteland and dry gravelly soils.” And the 1981 University Press of Virginia book, Trees and Shrubs of Virginia, adds “[w]ood borders, clearings, [and] roadsides”.

 

What do each of these locations have in common? Every single one of them results from people having impacted the soil at some point in a site’s history. Otherwise, the area would be filled with old-growth trees, the original landscape of eastern North America.

 

A 1998 Timber Press book, Trees of the Central Hardwood Forests, makes the mistake of telling the reader that the value of Mimosa is “[n]ot significant to any native wildlife species”. Indeed, this declaration has been much used by people, such as activist-entomologist Doug Tallamy, to disparage plants they view as alien invasives in need of removal. But I must beg to differ.

 

In 2019, I had the opportunity to document the life in the canopy (the upper layer of a mature tree) of a Mimosa. I had noticed this plant growing alongside a bridge I have crossed numerous times while exercising. As Mimosas are fast-growing trees, it didn’t take many years for this one to get large enough to bloom at the level of the bridge where I could observe the goings-on.

A day-flying Hummingbird Clearwing moth(Hemaris thysbe) is happy to feed upon nectar from a Mimosa-tree bloom.

In addition to this Spicebush Swallowtail butterfly (Papillo Troilus), you could see a Tiger Swallowtail (Papillo glaucus) and Silver-spotted Skipper (Epargyreus clarus), as well as small bees, obtaining nectar from Mimosa-tree blooms.

This large, healthy caterpillar was probably close to pupating after feeding upon the leaves (still closed here in early morning) of this nonnative Mimosa-tree.

Hummingbirds, small bees, several species of butterflies, a day-flying moth, and even caterpillars were getting food, courtesy of this foreign tree. Obviously, these animals could get food from native plants, if the appropriate plants existed nearby—and there’s the catch.

 

People seem to think “invasive” plants have stolen space from native plants that could be growing there, but most native plants can’t survive in the degraded soil where you typically find the nonnative plants designated as “invasive”.

 

I’ve found that what’s true for the Mimosa is also true of the many other so-called invasive plants that I’ve studied. The wildlife value of these plants is, without a doubt, certainly of significance when you consider that we are living in a world where development—that robs wildlife of habitat and destroys the soil profile for most native plants—never seems to end.

When people come upon “invasive” plants filling an area, they don’t consider its prior history of native-plant removal and soil damage that inevitably invited alien plants to grow there. The notion of “invasiveness” developed out of context to this bigger picture; without taking the whole story (i.e., background) into account, it’s easy to misinterpret the result.

Additional attributes of the so-called invasive plants—including Mimosa—is that they can withstand drought and often are tolerant of pollution, whether it be in the air or the soil.

 

Thanks to climate change, drought has become a more-frequent occurrence that can kill plants. (Along the river near where I live, some species of large trees are seriously suffering right now, even some located within the river!) Without drought-tolerant “invasive” plants, there could come a time when little habitat will exist. All plants, native or not, provide a living space for wildlife in some way.     

 

In a 1989 conversation with PBS journalist Bill Moyers, the novelist E. L. Doctorow, said, “When ideas go unexamined and unchallenged for a long enough time, they become mythological and very, very powerful. They create conformity. They intimidate.” His comments apply well to the “invasive”-plant narrative.

 

Orville Wright pointed out that, “If we all worked on the assumption that what is accepted as true is really true, there would be little hope of advance.”  I would adjust this truism to read that, “If we all work on the assumption that what is accepted as true about invasive plants is really true, there is little hope of conserving our wildlife.”

 

DISCLAIMER:

 

Ads appearing at the end of e-mail blog-post notifications are posted by follow.it as recompense for granting free usage of their software at the author's blog site. The author of this blog has no say in what ads are posted and receives no monetary compensation other than the use of the software. 

 

 

Dana Milbank (Washington Post Columnist) Should Perhaps Change His Name to Dana MilliVanillibank

For almost 40 years, my yard has hosted a mix of nonnative—some deemed “invasive”—and native plants. The abundance of wildlife it has attracted was such that I was able to write a book—The Nature-friendly Garden—based upon it.

ALL TEXT AND PHOTOS © Marlene A. Condon

You may remember the 1990 scandal involving Milli Vanilli, the German pop-music band fronted by two “singers” who had never sung one note of their songs. When performing publicly, they had simply lip-synced the songs that had been sung and recorded secretly by another person.

 

Likewise, Washington Post commentary writer, Dana Milbank, hasn’t truly written his own thoughts regarding so-called invasive plants in his column of April 7, 2023. You could say he simply lip-synced concepts publicized by Doug Tallamy, entomologist-turned-activist.

 

https://www.washingtonpost.com/opinions/2023/04/07/suburban-lawn-climate-change-biodiversity/ 

 

When Mr. Milbank posits that he’s “been filling [his] yard with a mix of ecological junk food and horticultural terrorists”, he’s channeling the kind of words Bringing Nature Home author Doug Tallamy loves to employ: Biased expressions that implant negative images in the reader’s mind so he will become yet another minion of this scientist. Nowadays you can’t read a garden or environmental column without being accosted with the same words or variations thereof, as if everyone has become a mouthpiece for Doug Tallamy, which I’ve never seen done more obviously than in this column by Dana Milbank.

 

The problem with all this parroting is that the basic message isn’t based on legitimate science or knowledge of the natural world (for a detailed exposé, please see “Chickadee Chicanery” at https://indefenseofnature.blogspot.com/2020/10/a-carolina-chickadeegrasps-tulip-poplar.html). There is also much repetition of mythical “facts” that are completely wrong (for a detailed explanation, please visit https://indefenseofnature.blogspot.com/2023/01/invasive-plants-friends-or-foes-marlene.html), placing their value on a par with gossip.

 

Still, following in the footsteps of numerous columnists before him, Mr. Milbank starts off denigrating “invasive” plants with false suppositions (that are highly likely to have come from Dr. Tallamy’s first book, a repository of misinformation from beginning to end):

 

“A few of the shrubs I planted were invasive and known to escape into the wild. They crowd out native plants and threaten the entire ecosystem. Our local insects, which evolved to eat native plants, starve because they can’t eat the invasive plants or don’t recognize the invaders as food. This in turn threatens our birds, amphibians, reptiles, rodents and others all the way up the food chain. [Emphasis mine because these statements are all untrue.] Incredibly, nurseries still sell these nasties — without so much as a warning label.”

 

Let’s dissect the Milbank statements above that I’ve written in italics:

 

·    “They crowd out native plants and threaten the entire ecosystem.” Read virtually any description of where you find so-called invasive plant species and you will find the word “disturbed”. This tells you the soil profile has been negatively impacted by people, animals, or weather, and usually means the topsoil is gone. Only very tough plants—known as colonizers—can grow in disturbed areas because the soil is nutrient-poor and is typically compacted. Consequently, these areas may fill with a mix of native and nonnative plants, or mainly one or the other—but every single plant is a colonizer that is working to rehabilitate the land for the benefit of the native plants that require topsoil in which to grow. “Invasiveness” is nothing more than a derogatory word used by people with contempt for alien-plant colonization. Conclusions: Alien plants can’t “crowd out” native plants because once the soil is disturbed and thus degraded, most of our native plants can’t grow there and thus are not there to be crowded out. As for “threaten[ing] the entire ecosystem”, to the contrary—alien colonizers are helping to restore it. 

·    “Our local insects, which evolved to eat native plants, starve because they can’t eat the invasive plants or don’t recognize the invaders as food.” This oft-repeated distorted premise comes straight out of Bringing Nature Home, in which Doug Tallamy deceptively writes about an “excellent demonstration of how restricted a specialist’s [an insect with particular food preferences] diet is.” Dr. Tallamy tells the story of Eastern Tent caterpillars on a cherry tree denuded of its own leaves but hosting a Japanese Honeysuckle vine. He writes that the caterpillars didn’t recognize the honeysuckle as food (sound familiar?). But, of course, they didn’t because this species of insect can only eat plants in the Rose Family, which does not include honeysuckle. The story is told in a perfidious manner, apparently to fool the uninitiated—the MilliVanillibanks of the world who fall for it, hook, line, and sinker, and then lip-sync it. What Doug Tallamy doesn’t tell the reader is that the tent caterpillars could certainly have eaten the so-called invasive Multiflora Rose, which I’ve documented in the photo below. Conclusion: Native insects did not evolve to eat only local (native) plants, but rather can typically feed upon dozens, if not hundreds or thousands, of plants related to each other by family classification, even though they grow in other countries.

Because the Multiflora Rose (Rosa multiflora) is in the same family as the Black Cherry tree (Prunus serotina), it can feed our native Eastern Tent caterpillars.

Now let’s look at other italicized (by me) Milbank quotes from the same Washington Post column.

 

·    “If you want to save the planet, all you really need to do is plant a single oak tree.” The columnist then quotes researcher and author Doug Tallamy, referring to him as the “godfather of the native-plant movement”, who says, “You can plant one tree. You don’t have to get rid of anything else.” Mr. Milbank then tells us to “leave the rest of your plants alone, for now. Tallamy ultimately wants to cut lawn acreage in half, but allows that ‘there is room for compromise,’ and ‘Think of your noninvasive plants and cultivars as ‘decorations.’” So, cultivars are now seen by Dr. Tallamy as eye candy and useless to wildlife, but it’s okay for you to keep them in your yard. Yet in his first book he had a different view, writing with nary a bit of humility: “I predict that in most cases, cultivars of native plants should be fine” in answer to a supposed reader question of “Is it all right to use [showy cultivars] or will insects treat them like aliens?” This question, of course, is asking whether leaf-eating insects will be able to feed on cultivars. Apparently, this academician has changed his mind about his confident “prediction”. The truth is that Doug Tallamy’s entire line of thought represents the epitome of hypocrisy and the dearth of logical thinking that lies at the heart of the entire “invasive-plant” movement. On the one hand, Dr. Tallamy and his followers proclaim that so-called invasive alien plants are a problem because native insects cannot eat them, then they say without any sense whatsoever of self-awareness that it’s acceptable to keep the alien plants they and you like, even though insects supposedly can’t eat those non-invasive alien plants either! This insincerity represents an astounding demonstration of either immorality or stupidity (“showing a lack of good sense or judgment”).

·    And Mr. Milbank provides an example of just what I mean here: “Janet Davis, who runs Hill House Farm & Nursery in Castleton, Va., has a similar [to Doug Tallamy] message for the purists who make you feel bad about your blue hydrangea. ‘Don’t give me crap about something that’s not native but not invasive,’ she said. ‘I’m never going to tell you you can’t have your grandmother’s peony.’ Yet, consider this truism: “Invasive” plants are often spread far and wide by critters that take the fruits and either drop some or pass the seeds through their intestinal tract after eating and digesting the fruit.  Question: What is the difference between a plant being spread by an animal that has made valuable use of it and a plant spread by people as they plant yard after yard with “hydrangeas, azaleas and roses”—which Mr. Milbank decided to keep, despite saying they represented “ecological empty calories”? In other words, it’s not allowable for wildlife to “grow” plants with food value that has helped them to survive, but it's perfectly acceptable for people to grow plants solely to provide aesthetically pleasing “decorations” (the word employed by Professor Tallamy when permitting this contradictory situation).

·    Therefore, if you like your so-called invasive plants (as I do), why should you listen to Mr. Milbank’s advice: “If possible, you should remove the nastiest of the invasive plants if you have them: burning bush, Japanese barberry, Asian bush honeysuckle, English ivy, callery (Bradford) pear and a few others.” Do you think it’s fair for him to keep what he likes, but we can’t keep what we—and, more importantly, our native wildlife—like? 

My yard disproves Doug Tallamy’s thesis that properties with alien plants can’t support the caterpillars that birds (and other wildlife, such as the Four-toothed Mason wasp [Monobia quadridens] seen here) need to raise their young.

 

·    “Worst was my row of nandinas — ‘heavenly bamboo’ — along the foundation.” “You definitely want to remove it,” advised Matt Bright, who runs the nonprofit Earth Sangha, a native-plant nursery in Fairfax County. “Its cyanide-laced berries poison birds.” Please note Mr. Bright’s choice of words to describe Nandina fruits: “cyanide-laced [emphasis mine]”, as if the plant has evil intentions, deliberately adulterating its fruits to kill North American birds. This tactic is typical of the MilliVanilliBanks in the U.S. who want folks to perceive supposedly invasive plants as “bad” even though no evidence exists to support their accusations, especially in this instance. Mr. Milbank and Mr. Bright, who obviously supplied this information, have misspoken here. A study out of the University of North Carolina out of Chapel Hill, published in 2022, explains that Cedar Waxwings are the only birds that might be poisoned, and that’s only going to happen if someone grows so many nandinas that these birds can consume large numbers of fruits in a single feeding bout. If you grow just one or even a few plants, you are not going to poison waxwings. On the other hand, the author of the study points out that, “as distressing and regrettable as these cedar waxwing deaths are, they pale in comparison to the harm visited upon songbirds in the United States from other anthropogenic causes. Free-ranging domestic cats kill 1.3–4.0 billion birds annually (Loss et al. 2013), collisions with windows in homes account for another 159.1–378.1 million deaths (Loss et al. 2014a), and a further 89–340 million birds are lost every year to vehicle collisions (Loss et al. 2014b). Against this appalling carnage, deaths of cedar waxwings from N. domestica [Nandina] toxicity are a mere footnote [emphasis—everything in bold—is mine].”     (https://ncbg.unc.edu/2022/05/04/nandina-toxic-to-birds/) The above quote thus affirms my take on so-called invasive plants, which is that this entire issue plays no real part in the decline of insect and bird numbers. (https://indefenseofnature.blogspot.com/2023/01/invasive-plants-friends-or-foes-marlene.html) 

  

Lastly, I want to point out that the reason Dana Milbank is so gullible, believing everything without question that he’s told by “experts”, is because he obviously possesses very little gardening knowledge himself, as exposed not only by his plural of “genus” as “genuses” (the correct form of which is “genera”), but also by the “advice” he offers others. Obviously, Mr. Milbank is ill-qualified to even be discussing this issue in a national newspaper, but he continues:

 

“Don’t have a yard? You can plant a native viburnum, goldenrods, asters, sunflowers and pussy willows in containers on a balcony or patio.” None of these species, except the asters, is particularly suitable for container gardening.

 

“Most people buy their lawn plants from Home Depot, Lowe’s, Walmart, Costco and the like, which either don’t offer native plants or offer those useless, engineered cultivars masquerading as natives. I had thought the magnolias, azaleas, hydrangeas and viburnums I bought were natives (there are native varieties of all these) but they turned out to be either the engineered types or even Asian varieties.” What a surprising admission from a man whose vocation requires research! Nothing precluded this Yale graduate from simply looking up the scientific names of native plants that could be used in his yard.

 

The Azalea caterpillar (Datana major), the larva of a native moth, is a known (in horticultural circles) “pest” of nonnative cultivated azaleas, as seen here in my yard. In other words, the Asian plants Dana Milbank disses as “useless, Asian varieties” can and DO support some of our native caterpillars, making his (and Doug Tallamy’s) overstatement untrue.

Additionally, he “took a small step in the painful task of killing [his] beloved lawn. [He] used landscape fabric to smother about 400 square feet of turf. In its place, [he] planted a smattering of canopy trees (two white and two northern red oaks), understory trees (ironwood, eastern redbud), shrubs (wild hydrangea, black haw viburnum) and various perennials and grasses (Virginia wild rye, blue-stemmed goldenrod, American alumroot, woodrush, spreading sedge).” No seasoned gardener would plant this many large woody plants—especially four oaks that will ultimately become huge and shade out everything else—in such a small area! Dana Milbank is a plant salesman’s dream come true: a person trying to crowd in as many plants as possible without proper thought to the future needs of all these plants—space to spread out and grow into their natural form without being crowded and thus made susceptible to disease; enough room around them to obtain all the nutrients and water they need; and the ability to still get enough sunshine throughout their lifetimes.

 

“Right now, my seedlings look pretty sad. Where once there were healthy lawn and vibrant shrubs, there is now mud and scrawny sprigs poking from the ground every few feet. I put up chicken wire to keep the kids (and me) from trampling them. The carcasses of my invasive plants lie in a heap on the gravel.” This statement supports my contention that ridding your yard (and, in the case of government, natural areas and parks) of “invasive” plants destroys habitat, leaving our wildlife high and dry. Follow the advice of Doug Tallamy via Dana Milbank (and many others) and you make the environment far less hospitable to our wildlife by removing plants that supplied habitat NOW when our critters need it to survive.

 

Removing plants for development permanently takes away habitat and thus is far more of a problem for wildlife than so-called invasive plants, such as the Autumn Olive (Elaeagnus umbellata) seen here, that DO support wildlife.

Wildlife can’t wait for the future growth of new plants, as these people think: “But in a couple of seasons, if all goes well, [Milbank’s] yard will be full of pollinators, birds and other visitors in need of an urban oasis. Years from now, those tender oak seedlings, now 6-inch twigs, will stretch as high as 100 feet, feeding and sheltering generations of wild animals struggling to survive climate change and habitat loss. I won’t be alive to see it. Yet even now, my infant oaks give me something the most stunning cherry blossom never could: a sense of hope.”  Mr. Milbank, obviously having bought into Doug Tallamy’s more-recent book, Nature’s Best Hope, should have welcomed “pollinators, birds and other visitors” with the full-grown specimen plants he already had, but he must never have looked for these organisms. My property is a mix of alien (including quite a few deemed “invasive”) and native plants, and my yard has always teemed with wildlife of every sort. (www.marlenecondon.com)

 

Although it may sound logical that native insects can only obtain nourishment from native plants they co-evolved with, the reality is that they can—and do—feed upon nonnative plants. Here, a Tiger Swallowtail butterfly is getting the nutrients it requires from a nonnative Glossy Abelia (A.grandiflora) in my yard.

 

“When it comes to the world’s biodiversity crisis — as many as 1 million plant and animal species face near-term extinction because of habitat loss ― I am part of the problem. I’m sorry to say that if you have a typical urban or suburban landscape, your lawn and garden are also dooming the Earth.” No, the Earth’s doom is approaching much more rapidly thanks to people like the ones mentioned in Dana Milbank’s column who believe erroneously that alien plants serve no function in our landscape, and so they destroy functioning habitat, often by adding pesticides (poisons) to the environment.

 

Media promulgation of the mythological idea of “invasive” plants is hastening the arrival of a world in which humans will not be able to live.

NATURE ADVICE:

Dana Milbank’s column makes clear he’s not someone who should be writing about the subject of nature-friendly gardening, and he’s certainly not the person you should trust for advice on this subject. He may work for a national newspaper, but he’s a cheerleader, rather than an informed, objective writer and gardener.

 

DISCLAIMER:

 

Ads appearing at the end of e-mail blog-post notifications are posted by follow.it as recompense for granting free usage of their software at the author's blog site. The author of this blog has no say in what ads are posted and receives no monetary compensation other than the use of the software. 

 

 

Alien Plants Benefit the Environment

A native Eastern Tent Caterpillar feeding upon an alien Multiflora Rose shrub in Albemarle County, Virginia.

ALL TEXT AND PHOTOS © Marlene A. Condon

 Originally published in The News-Virginian (Waynesboro, Virginia daily newspaper) on October 27, 2022

 

https://newsvirginian.com/opinion/columnists/condon-many-alien-plants-benefit-the-environment/article_5d18e73c-557c-11ed-8f02-8375034e2011.html

 

On June 8, 2011, the journal Nature published a commentary by 19 ecologists who urged conservationists to “assess organisms on environmental impact rather than on whether they are natives”.

 

https://www.nature.com/articles/474153a

 

“Classifying biota [the plants and animals of a region] according to their adherence to cultural standards of belonging, citizenship, fair play and morality does not advance our understanding of ecology [the relations of organisms to one another and to their physical surroundings]. Over the past few decades, this perspective has led many conservation and restoration efforts down paths that make little ecological or economic sense”.

 

This other side to the story regarding alien species—in particular, nonnative “invasive” plants—is rarely publicized, yet it needs to be. It’s been eleven years since this essay appeared and was ignored by virtually everyone. As a result, the general public, government at every level, scientists, the media, and especially environmental groups and the people that support them have now instituted a scorched-earth policy that’s bringing about much destruction of viable habitat and the poisoning of our environment via herbicides.

 

Many people fervently believe that so-called invasive alien plants pose a dire threat to native insects, undoubtedly due to the 2007 book, Bringing Nature Home, by entomologist Doug Tallamy. In it, he wrote that “scientists who know what they are talking about” developed “an extensive body of theory” that predicts that native plant-eating insects “should be able to eat only vegetation from plants with which they share an evolutionary history”.

 

This assertion, which holds that herbivorous insects eat only those plants they have co-evolved with under the same environmental circumstances, sounds logical to the uninitiated. However, it disintegrates under scrutiny.

 

Dr. Tallamy tells us that these 6-legged critters that feed upon plant tissues are limited to feeding upon “no more than a few plant lineages [a single line of genetic descent through time]”, thus making them “specialists”. However, each plant lineage can include hundreds, if not thousands, of species around the world—which means an insect is likely to be able to feed upon at least some of the plants that are related genetically, regardless of their country (geopolitical boundary) of origin.

 

In other words, specialist insects aren’t usually limited to just one plant species, contrary to what this University of Delaware professor would have his readers believe. Because we know that countries share plant lineages (and even some species), phytophagous (herbivorous) insects should be able to eat vegetation from other areas on the Earth even though they evolved in concert with only some of the plant species in a lineage—and, indeed, they do.

 

In Bringing Nature Home, Doug Tallamy recounts the plight of native Eastern Tent caterpillars (Malacosoma americanum) that ran out of cherry leaves on a tree too small to feed them adequately. He mentions that leaves were still available to the caterpillars in the form of a Japanese Honeysuckle vine (Lonicera japonica) that had climbed the little tree, but he points out that the caterpillars “had not taken a single bite out of the alien plant…even in the face of starvation”.

 

This tale gives the reader the impression that the caterpillars could have eaten the honeysuckle if only it had been native, thereby having evolved with the insect. He does not point out that the caterpillars would have faced starvation even in the presence of a native vine, tree, or shrub if—like the alien honeysuckle—it wasn’t a member of the Rose Family, as is this caterpillar’s preferred native host plant, the cherry.

 

Several native Eastern Tent caterpillars feeding upon an alien Multiflora Rose shrub in Albemarle County, Virginia.

I have documented myself tent caterpillars feeding on a relative of the cherry—a nonnative, unevolved with, and much despised Multiflora Rose (Rosa multiflora) growing at the base of a leaf-stripped Black Cherry tree (Prunus serotina).  A factuality is that you can find native insects feeding upon nonnative plants, but, of course, you need to look!

 

People have been manipulated into believing alien plants serve no ecological purposes in the environment, when, in fact, they very much do, in very many ways, for innumerable insect (and other) species. As the 19 ecologists wrote in their paper, “[A] valuable step would be for scientists and professionals in conservation to convey to the public that many alien species are useful”, and that “Natural resource agencies and organizations should base their management plans on sound empirical evidence and not on unfounded claims of harm caused by nonnatives.”

 

Amen.

 

 

NATURE ADVICE:

 

Don’t remove alien plants just because they are alien plants. If you see critters using them, ask yourself if putting in new plants will immediately provide as much food and shelter/nesting sites as the nonnative plants presently there, or will it take many years for the new plants to provide habitat. Plant natives where you are increasing the amount of habitat on your property, rather than where you are destroying it.

 

Time to See the Light Regarding Loss of Insects and Birds

This Christiansburg, Virginia, plaza could be planted with native trees and still not support caterpillars, thanks to the excessive lighting that is a prime killer of moths.

Plenty of native trees exist in the eastern United States to support moth caterpillars, but when moths spend the night circling artificial lights—such as the street lamps seen here among an abundance of large native trees—they die without reproducing.

ALL TEXT AND PHOTOS © Marlene A. Condon

Originally published in The News-Virginian (Waynesboro, Virginia) on July 16, 2022

https://newsvirginian.com/opinion/columnists/condon-time-to-see-the-light-regarding-loss-of-insects-and-birds/article_6d0f3322-03eb-11ed-8317-53ceb5edb5ab.html#tracking-source=home-top-story

On summer nights, when I was a child, my mother would scream at us kids to quickly get into the house before all the insects (mainly moths) circling our carport light had a chance to come inside with us. Nowadays, I can put on my own carport light with hardly any insects—certainly not moths—coming to it.

The reigning assumption regarding the loss of insects and birds (derived from research published in 2017, “Native plants improve breeding and foraging habitat for an insectivorous bird”,

 

https://www.sciencedirect.com/science/article/abs/pii/S0006320717305153)

 

is that the most crucial step people can take to save the environment is to grow native plants. But is this theory truly the environmental panacea for our time?

 

Bringing Nature Home by Doug Tallamy also stressed the importance of growing native, rather than nonnative, plants. In this book, the author showed a nighttime image of the United States aglow with lights [page 28, 2007 advance reading copy]. He captioned it, “A composite image from space of the United States at night shows the extent to which we have converted natural areas [i.e., native plants] to developed landscapes [i.e., alien plants]”.

 

True enough. However, the more ominous takeaway is the dire effect of all those lights upon insects, especially the moths whose caterpillars have always been essential to birds raising their young. These larvae are now largely gone because adults are largely gone. Moths that circle lights all night until they are exhausted, or where they are easily caught by predators (such as bats and owls), are moths that don’t reproduce.

 

Why am I so sure that lights are the problem rather than a decrease in the number of native plants? I’ve lived in my home for more than 36 years. My yard has always been surrounded by mature oak forest, and I’ve watched through the decades the trees growing so tall that I can no longer view the Blue Ridge Mountains only a few miles to the west.

 

Nevertheless, despite the ever-increasing woody mass of native trees and shrubs around me, the numbers and kinds of insects and birds have decreased in my yard, just as they have elsewhere. I’ve never employed pesticides on my property, and I have gardened in full agreement with Mother Nature (hence my 2006 book on this subject).

 

The argument that there’s not enough native woody plants doesn’t work here because mature forests have comprised a substantial percentage of my property as well as the surrounding area. In fact, this idea doesn’t apply to much of the eastern United States.

 

Travel in a plane between New England and the South or fly in a hot-air balloon over your local area, and—unless you live in the concrete jungle of a city—you are going to observe plenty of large native trees in yards, parks, and “natural” (i.e., managed) areas.

 

In 2017, German researchers made world-wide headlines with their paper published in the journal, Nature, in which they detailed their own discovery of insects disappearing. Many suggestions have been put forth for the loss, including such things as pesticides (over 1 billion pounds a year are deployed in the United States, https://www.brownfieldsummit.com/how-many-pesticides-are-used-in-the-us) and loss of natural habitat due to development.

 

None of these considerations explains the loss of insects on my property over the course of almost four decades. A more plausible explanation is the ever-increasing number of lights needlessly burning all night around homes, churches, schools, libraries, businesses, barns, vineyards, American flags, and in parking lots and even national parks. Indeed, despite living in a rural area, it’s now difficult for me to view the Milky Way, thanks to light pollution.

 

Light constitutes an insidious menace because its allure to insects is so strong and its effect upon them so deadly, while people are oblivious to its ramifications. There’s no harm in growing more native plants, but this action is not going to prevent the loss of more insects.

 

If you truly want to help our insects and birds, you need to shut off lights burning all night, every night, for no good reason. Then we might see a light at the end of the tunnel for saving what’s left of our insects and the birds dependent upon them.

NATURE ADVICE:

 

In addition to limiting the amount of time you leave exterior lights burning after dark, you should take into account the amount of light exiting your windows. This light also attracts insects and keeps them “glued” to windowpanes instead of reproducing. To prevent light from escaping your windows, please use curtains or blinds.

 

And please keep in mind that lighted yard decorations also contribute to the loss of insects.

 

 

Missing the Forest for the Trees

A male Eastern Towhee perches on a radio tower enveloped by an Autumn Olive shrub—perhaps the best wildlife plant there is as it feeds numerous species of pollinators, birds, and mammals.

ALL TEXT AND PHOTOS © Marlene A. Condon

 

There’s much publicity nowadays that misinforms people about the need to create a wildlife habitat in which 70% of the plants are native. A major focus is often on getting folks to grow trees—in particular, oak trees. Why? According to Nancy Hazard, a member of a group called “Greening Greenfield [Massachusetts]”, “Oak is king. Oaks host over 400 different species of moths and butterflies.”

 

https://www.recorder.com/Ecological-difference-39423618

 

This deceptive “fact” (which comes from entomologist Doug Tallamy, whose tally for caterpillar species that feed on oaks was 557 in 2017, according to the National Audubon Society) is repeated often in gardening columns, making people think that any oak they grow in their yards is going to feed hundreds of species of moth and butterfly caterpillars.

 

https://www.audubon.org/news/new-research-further-proves-native-plants-offer-more-bugs-birds

 

The reality, however, is that this number represents the sum of Lepidopteran species that feed upon the entire genus of oaks across the country, of which there are at least 90 species. In other words, if you plant a White Oak (Quercus alba) in your yard, it’s not going to feed nearly as many caterpillar species as you might think.

 

Why the focus on tree-caterpillar species anyway? The study that supposedly proved that at least 70% of the plants in a yard should be native for the benefit of songbirds was based upon the foraging habit of Carolina Chickadee parents getting food for their chicks. These small birds mainly feed their young tiny caterpillars that they find on forest trees (their ecological niche) which, by definition, consists of native species.

 

Although Doug Tallamy and his coauthors, student Desiree Narango and ornithologist Peter Marra, concluded in their original paper that the Carolina Chickadee requires native trees (which should have been obvious even without a study) to reproduce successfully, their observations are now employed by virtually every garden columnist and TV gardening personality to mean all bird species require 70% of the plants in people’s yards to be native. But this contention was not proven by the study everyone references, and therefore Narango, Tallamy, and Marra should have set the record straight by now.

 

https://indefenseofnature.blogspot.com/2020/10/a-carolina-chickadeegrasps-tulip-poplar.html

 

However, these scientists do not seem to comprehend or value the larger picture because they are so focused on only a fraction of it. They’ve been missing the forest (the rest of the environment) for the trees (especially those oaks).

 

Dr. Narango “believes that her results provide convincing evidence that planting native is in a bird lover’s best interests. ‘The trees [our color-banded chickadees] were going to were covered in warblers, tanagers, and orioles,’ she says. ‘They’re basically telling us what these other birds want.’”

 

https://www.audubon.org/news/new-research-further-proves-native-plants-offer-more-bugs-birds

 

Yes, the chickadees were telling her what warblers, tanagers, and orioles want because these species are birds of the forest, as is the chickadee. To assist such birds requires that your yard and every yard around you must become forest, something highly unlikely to occur in urban/suburban areas.

 

Additionally, this newly minted scientist fails to recognize that the forest habitat of these species is not what all other birds want. If everyone made their yards forestland, we’d lose our common backyard species—Eastern Towhee, Northern Cardinal, Brown Thrasher, and Song Sparrow, to name a few—that require shrubby habitat, not forest. Sunny shrubland with herbaceous plants and woody shrubs supports far more diversity of insect life than forest, including an abundance of mammal, reptile, salamander, and bird species. And truth be told, numerous nonnative shrubs and herbaceous plants support these organisms very well.

 

https://www.marlenecondon.com/

 

For the greatest diversity of life forms, our landscape cannot consist solely of forestland, which is what Tallamy, Narango, Marra and their followers are pushing for, even though they don’t seem to know it.

 

NATURE ADVICE:

If most of your plantings are already native species, that’s great—if they provide the proper structure necessary to create good wildlife habitat. Problems arise when people feel they are obliged to get rid of fully mature nonnative plants, especially by way of pesticides, even though the resulting bare ground or young (immature) newly planted native plants will not be useful for a long time to come.

Alien plants can provide habitat for shrubland bird species, whether it be by providing nesting sites, food (fruits/seeds), or cover. It’s a huge mistake to destroy habitat that functions perfectly for shrubland birds. Please don’t be swayed by the harmful information perpetuated not only by the media, but also scientists who dare not speak against a popular thought, even though it is wrong.