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Doing Something About the Infection

(top) BURNING BUSH dominating the understory in a central Indiana wood in fall; (bottom) CALLERY PEAR taking over a field (the smell of its spring flowers has been likened to dirty socks, rotting fish, old semen and vomit, Dirr's descriptor {malodorous} is more genteel but less specific). Both scenes are at once beautiful and terrifying, but I suspect 95%+ of the general public would choose the former, which is depressing as well as a serious and perplexing challenge. Consider this: many people I attempt to persuasively educate about Callery pear, and who did not know of the stinking flowers, reflexively get defensive, often denying that fact (the stink) or saying something like, I still like the plant. How's that for close-minded illogical? My experience leaves no doubt that many of us need an adjustment, perhaps a reality pill. By the way, this pear tree can produce dense and dark thickets of specimens with thorn-tipped shoots. These thickets are quick to develop and difficult to walk through. *


In many previous posts I have commented on the severe ecological and landscape maintenance issues caused by a small number of horrible invasive exotic plant species. Few places remain unaffected, with the quantity and species varying by location. I am not alone in having suggested we refrain from buying and using the culprits and that we should steadfastly attempt to eradicate those found on property we manage or care about, particularly in and near natural areas. However, I have not, until now, focused on the businesses who sold and continue to sell these monsters. In so doing, those vendors put their financial gain over the health and integrity of "our" landscape.

The Midwest has a few dozen of these horrible invasive plant species, some terrestrial, some aquatic. They are attractive or otherwise enticing taxa which, once released, spread uncontrollably. Unwanted and ill-advised "additions" that keep on giving. Prevention and quick intervention are key. There is no reset button! Unfortunately, the message both falls on deaf ears and has gotten confused . . . becoming more of a good native v bad nonnative issue AND focused on a hoped for fix (a cure) with replacement parts (like repairing a machine). Moreover, the scope of the attempted remedy is woefully insufficient! Do the math! Unfortunately, the way many of us have chosen to deal with the issue is ignorance, denial and irrational optimism.

For years concerned citizens have asked nicely and pleaded with merchants to stop supplying the horribles. Thankfully, some did. Alas, many dealers evidently do not care. Well, enough is enough. I do not think it wise to wait while the problem gets worse. Indiana finally did pass a law (2019) that bans "the sale, offering/gifting, barter, exchange, distribution, transport, or introduction" of 44 invasive terrestrial plant species -- the ban applies to businesses AND individuals, regardless of source. We have the law (the ban) thanks in large part to the outstanding long-term lobbying of former TNC ecologist Ellen Jacquart -- the culmination of remarkable effort by a dedicated conversationist. My friend Fran Harty was the prime mover behind similar legislation in Illinois three decades earlier! See his publication How Illinois Kicked the Exotic Habit, *** but even back then the law was too late to prevent the problem. By the way, some of the invasive species are far worse than others, especially the two species highlighted in this blog. Moreover, and this is an important point, only about 1/4 of the 44 recently banned species were ever actually available for sale at gardening outlets. -- I am certain that some environmental extremists, especially the misguided purists, will not like that I highlight these facts since they do not strengthen the nonnative hate campaign. Too bad. For the umpteenth time, the vast majority of nonnatives plants are benign and the impact from the nonnative Homo dwarfs all others.

Like with another environmental problem primarily of our making (climate warming), we are having to figure a way to adapt, to live with the impact (the change, which will be ruinous "no mas" for some organisms and places). But we must also mitigate any additional damage. For the invasive plant problem it means removal of as many of the specimens as possible AND preventing more from being imported/added, thus the need for banning. Additionally, we need to understand that the invasive species problem is much more than a gardening matter, it is also a key factor in safeguarding biodiversity (i.e., species survival) . . . a critically important ecosystem issue that does not seem to register with most people. Moreover, climate warming and invasive species are both "our" problems and existential threats! Let me reframe that as a Q, How does one unburn a house or unkill a organism?, or more plainly, it means a threat that could cause the extinction of untold species!! Many of these are insects that we depend on to pollinate food crops! If that does not get your attention then you are a fool we are fucked. We cannot let denial, habituation and greed delay or prevent what needs to be done, and we need to be together in this fight. There can be only one side. These problems, and the resulting slow cascade of negative effects, are not imaginary, nor are they going away. How we handle these crises are clearly two of the most important decisions mankind has ever faced! While depressing and unpleasant to contemplate, WE will have to make some drastic behavioral (life style) changes very soon in order to give ourselves a chance. I would like to be optimistic, but sadly the vast majority of us are clueless and could not care less, more worried about the big game or other trivial matters. Someone else can deal it . . . playing while the house burns. Tipping point is a term and concept that you need to understand. Sadly, we are likely at or past it for both issues.
Having made the case for everyone needing to contribute to "our" cause, it may surprise you that I continue to find some of the banned species as well as other well-known invasive plant taxa offered for sale by garden outlets in Indiana more than three years after the law went into effect (April 2020). As with any law, enforcement is necessary but there are only 12 people assigned to cover the entire state (92 counties). By the way, the contact number to report Indiana violators is 1-866-663-9684 (or In a Sept 23, 2021 article published in The Herald-Times (Bloomington, IN) the director of the state division (entomology & plant pathology) tasked with ensuring these banned plants are not sold in Indiana asked people to contact her office, "so they can remove the plants from store shelves as soon as possible." No doubt the job should require the compliance personnel be on the road much of the time so, if you call, expect to get a voicemail message and do not hold your breath waiting for a response. I called twice in April (2023) and again in July. I left messages with my number, indicated who I was, and asked that my call(s) be returned. As of this posting, 4+months later, I am still waiting. This inaction makes me curious what, if any, enforcement actions have transpired in the 3+years since the law went into effect. It's possible the legislators expected, perhaps wanted, mostly self-regulation . . . like that was ever going to happen. Moreover, we should not need a law to do the right thing! -- FYI, established plants (placed in-ground before April 2020, and left there) are grandfathered in, although by allowing specimens to exist we are permitting most of the excluded actions via the reproductive strategies of the various species. Further, while the Indiana legislation is commendable, as noted earlier it occurred several decades too late. Much of Indiana and the Midwest already have been overrun by invasive exotics. For example, there are many millions of Asian bush honeysuckle(s) and winter-creeper specimens, two of the banned species, naturalized in most Indiana counties, perhaps all, as well as in surrounding states, and the number of specimens increases while the infected locations continue to expand exponentially. The 2020 Indiana law, and others like it, end up being something like considering stopping smoking only after learning you have lung cancer, with some saying to hell with it and continuing. Again, and unfortunately, there is no reset button! It is delusional and perilous to think so.

The words we use are important, they send a message. Alas, sometimes the message is sent too late or is not received. Sometimes the message is confusing. It is unfortunate and inappropriate that the call name (the anagram) chosen for the Indiana DNR call line is xxx-NO-EXOTIC. Again 99%+ of exotic plants are benign. Why not xxx-INVASIVE? By the way, corn and soybean are exotics.

As for a hoped for remedy by law, the 2019 Indiana legislature refused to include several of the worst invasive plants readily available in commerce. Why the exclusion? Pushback, or the presumption of same, from commercial interests coupled with the standard developer favoritism and environmetal disregard we have come to expect from way too many of our elected leaders. Maybe we should refer to the problem as a homeland security or public safety issue? Know this, environmental issues ARE economic issues! Further, it is more than interesting that eco- (from the Greek oikos, meaning house) is the root prefix for both ecology (-study of) and economy (-management of).
Q: why should "we" pay a perpetual environmental price for bad investment decisions by businesses that grow and sell the invasive plants? These species cause what is essentially an incurable degrading and destructive infection of the landscape, much like a skin disease. And here's a sobering thought: the infection is so advanced, in large part because we waited so long, I suspect that not even a totalitarian system of governance could succeed in alleviating the existing invasive plant problem . . . there is no putting the monsters back in a box and their reproductive potential is mind-boggling! Frankly, it WILL get worse even if we act, but by acting we can reduce the severity of the consequences. Again, they ARE NOT going away! FACT: there is a real accumulating cost for waiting to act!

Accordingly, since the 2020 invasive plant ban did not go far enough, I am here calling for all midwesterners (individuals and contractors) to stop planting and ALL garden centers to immediately stop selling

CALLERY PEAR (Pyrus calleryana) all cultivars *
WINGED BURNING BUSH (Euonymous alatus) I refer to it wishfully as Burn The Bush

Both species have long been known to be aggressively invasive (see pics above) and have been commonly sold. Removing them from commerce will help and it will also inform. The widespread lack of understanding regarding the cause and effect is troubling. For example, I cannot begin to tell you how many people, including a couple of garden store owners, I have heard say, but I like it, it's so pretty, why did they have to ban it?, or something similar, in referring to Japanese barberry and others on the banned list. Clearly we need to do a better job of getting the message out, and I have concluded that drastic and scare tactics may be necessary as pleading with reasoned explanation clearly is having limited impact.

So, here's my plan: if a garden center you shop at offers these plants, or any others already legislatively designated as forbidden, I call on you and your friends to do something about it. Specifically:
(1) tell them they should stop, and why (but don't use the ignorant "because they are nonnative" argument),
(2) refuse to shop there until they comply, and
(3) if they refuse to comply, call them out using social media and the hotline # listed above. Additionally, I recommend using social media to organize a general boycott unless or until the business(es) comply. I do not use social media but feel free to say that THE MAD BOTANIST told you to do it. A call for action! The owners should know better than to offer these marauders . . . most do, simply feigning ignorance and behaving in an environmentally irresponsible manner to make a few bucks. They may not care about the potential and real long-term environmental (home) damage, but some of us do, and all of us should. I considered suggesting a widescale girdling campaign for the pear but decided it was too militant (for now) and the specimens might simply root sprout, many roseaceous species do, and the woody skeletons would persist. -- By the way, we should consider doing a similar banning or curtailing action with the systemic herbicides referred to as neonics thereby forcing us to address the plummeting insect population crisis and the need to change cultural practices since doing so could provide similar pest management results without wrecking and poisoning the environment.

Some among us balk at prohibitions because we do not want to be told what we can or cannot do. I get it . . . I lean libertarian . . . but in any society there have to be some restrictions, things you and I are prohibited from doing when the action or inaction infringes on the rights of others and causes damage, like trespassing and starting an unmanaged fire in a public area. Well, planting either of the species listed above, as well as any of the now banned species, is like starting a living fire that cannot easily if ever be controlled or extinguished. And like with fire, infections spread . . . seeds are analogous to embers . . . thus trespassing. I am simply asking that we (1) use common sense and wisely not start any new "biofires" and (2) attempt (do our best) to check the vast number of biofires (invasive plant lesions) already visible. See the pics above for a landscape ablaze. Moreover, there are a few other species I could add to the should be banned list ** but only spotlight two to make it easier for the businesses to comply. -- In case you are curious, periwinkle (Vinca) and Chinese silver grass (Miscanthus sinensis) were next in line and will be covered in future posts, Further, I am posting this message in early fall to give businesses plenty of time to avoid making the mistake of including them in their 2024 orders.

If any of the purveyors do not comply, we can show them our displeasure and resolve by the power of the purse AND by using the right of free speech and peaceful assembly to protest their role in this problem. We could also contact the media to inform them of our intended social activism, and why. Let's call it black eye PR . . . a Howard Beale approach. While we should want plant related commerce we also should demand that such businesses act responsibly. If they are unwilling to comply and suffer from their stubbornness, too bad. They were forewarned -- I already gave several central Indiana businesses a heads-up about my intentions. Nor should we accept the excuse that they only have the plant(s) for sale because a customer requested the thing. Further, I have heard several owners say it is not their fault, that they are simply trying to make the consumer (the user) happy, which is unacceptable pure avoidance BS! Our action will help/force the violators to do that which they apparently are unable or unwilling to do on their own volition, that is, the right thing. Just say no! But understand that the goal is compliance, not punishment . . . in order to help keep a serious problem from worsening too much. I recommend this in-your-face method because the situation is urgent, but pressure is NOT the best way forward. We need to comply because we understand the problem and then be willing to contribute to a concerted remediation effort. If we have to rely on forced action we are doomed. The key is education (prevention and removal) and we have no time to waste.

* As recently as the early 1990s most of the spring white flowering trees in the midwestern landscape were serviceberry and/or flowering dogwood. Today, that white, both urban and rural, is almost entirely Callery pear . . . . an alluring yet horrible plant that we continue to propagate. Why? Largely because of habit, ignorance and misinformation, e.g., I saw this marketing lunacy on the internet recently, "one of the best ornamental trees available." Well, consider this: a single mature Callery (a fast-growing species with wide ecological amplitude) can produce tens of thousands of small (marble-sized) speckled greenish-brown (then to dark brown) inedible fruits (hard at first and then softening and messy in winter) each pome with 2-4 cyanide-laced seeds, which are largely bird dispersed, and there are MANY millions (now likely a billion or more) of such trees, many intentionally planted but mostly wild growing (naturalized) in every Indiana county! Even if we could get rid of all the existing trees, saplings and seedlings there is a "keeps on giving" seed bank to contend with, and it is prodigious. By my estimate, the bank equates to well north of 1,000,000,000,000 (that's trillion, one thousand billions) potential new seedlings per county every year!! and the infection extends way beyond Indiana. The quantity is impressive for a plant that when first introduced was promoted as being sterile (fruit- and seedless -- we've heard that before) and the estimated number does not factor in new trees produced asexually. Further (brace yourself), I have read that breeders are developing cultivars that are more cold hardy!!! Perhaps Dylan should add a verse to North Country Blues. What won't we do for $? In addition, I am both hopeful of and frightened by what the consequences of an attempted modern biology remedy might be. Makes me think of what Harty would say to Laurel, "here's another nice mess you've gotten me [us] into." Or, as I always tell my advisees, just because we can, does NOT mean we should. Like this beyond stupid solution suggestion a Hoosier lady master gardener voiced when I attempted to explain the problem -- "but the trees [pears] are so pretty . . . if we just get rid of all the birds we can prevent the dispersal and keep those nasty things [she meant the birds] from shitting on our patios." She was serious. I was dumbfounded. -- Also, reread intro pic legend and see Chapter 96 (The Worst of the Worst) in my Rantings book as well as my May 2021 rant Callery Pear - A Crap Tree; also checkout the excellent The Rise and Fall [literally] of the Ornamental Pear Tree by T. Culley, Arnoldia 74(3)

** I recently conducted a survey of 25 expert field botanists with >1,000 years of combined field experience in the Midwest to help narrow and rank the field. Related, I attempted to include running bamboo in the short list but for numerous reasons decided doing so was inappropriate. Instead, I am crafting a separate treatment covering bamboo that I will post in the spring of 2024. In that blog I will elaborate on my reasons for the separation. I conducted a similar survey while at the Illinois Natural History Survey in 1986 and you may be startled when I tell you that only a few of the 25 participants listed Callery pear, and no one included garlic mustard! If done just a few year later, I suspect one or both would have made every list. Now, a mere 37 years later, I think Callery would be ranked the number one invasive plant in the Midwest by many, although there is competition! By the way, 1986 is about when the steady increase in climate warming started to become obvious (i.e., the inexorable penalty phase kicked in). I bring both these to your attention to illustrate just how fast things can change, for the worse. Again, too many people and unwise behavior. FYI, The world population quietly topped 8 billion last year (eight thousand millions)! The net increase is equal to the population of the 16 counties that comprise Chicagoland (i.e., 9.5 million every 45 days) or yearly more than the combined populations of California and Canada! Nonstop! Unless or until we check our numbers AND behavior, there is little long-term prospect for hope, and near-term will be worse, no matter what . . . the lag effect I alluded to earlier. In case you are curious, experts estimate that the comfortable/reasonable carrying capacity is 1.5-2 billion :( Look in a mirror, what you see is both the problem and, hopefully, the solution.

*** Refer to the 1991 symposium I organized, Biological Pollution: The Control and Impact of Invasive Exotic Species


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