Huánglóngbìng

Remember when I wrote about Panama disease, the fungal blight which is coming for the Cavendish bananas (after laying waste to the Gros Michel cultivar bananas back in the 50s)?  Well, sadly, Panama disease is not the only apocalyptic fruit blight on the international circuit these days.  It turns out that a bacterial disease is destroying citrus groves around the United States and beyond.  The disease, known in English as “citrus wasting disease” is caused by a motile bacteria, Candidatus Liberibacter, which is spread by the Asian citrus psyllid (Diaphorina citri), an inconsequential Hemipteran insect which lives in citrus groves.  There are multiple strains of greening disease, and there have been for a long time, but the newly problematic strain originated in China where it is known by the evocative name “huánglóngbìng” which means “Yellow Dragon Disease.”

A revolting Asian citrus psyllid, Diaphorina citri

The wild ancestors of most of today’s grape fruits, oranges, and lemons, came originally from the forests of East and South East Asia so it is not a huge surprise that this horrible disease comes from there too.  Unfortunately hemipteran insects can easily proliferate in new ecosystems, so the disease became a problem after these invasive insect pests gained a widespread foothold throughout the semi-tropical regions where citrus is grown.

A tree infected with citrus greening disease

Citrus fruit is delicious and wonderful beyond compare…so it is worth big money.  This means that agricultural scientists have been studying huánglóngbìng and attempting to stymy it with medicines, pesticides, and transgenic tinkering.   The scientists themselves have been hampered in their research by the fact that it is hard to maintain and study citrus plants infected with the disease because they die so swiftly (the infected citrus plants, not the agricultural scientists).  Powerful antibiotics work to wipe out the disease, but it is not practical to give these medicines to trees (though we will probably try—with predictable results).  Scientists feel that there may be a transgenic solution, but it is unclear how marketable such a chimera will be (since protectionists and Luddites have been fear-mongering pretty hard against GMOs).

This leaves mass application of insecticide as the best bulwark against huánglóngbìng.  It is starting to seem that small orchards and groves which are unwilling to commit to this kind of regimen will soon be gone.  All of this strikes me as unbearably sad and frightening.  Why are there so many blights everywhere?  Has this always been a peril of agriculture (indeed of life?) or has contemporary monoculture paved the way for widespread proliferation of these superbugs?  There must be some parasitoid wasp or something which has kept these damn psyllids from wiping out species citruses of wild Asia.  Maybe we could bring that here…but it probably would cause some new horrible problem.

We’ll keep you posted.  In the meantime you should glut yourself on oranges this winter…while you still can.

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The Return of Panama Disease

Australian Banana Groves Destroyed by Panama Wilt

Sooo…I try to keep it light on Mondays so we can get through these long weeks, but one of our recent posts demands an immediate follow-up.  Remember how I was discussing the grim fate of ‘Gros Michel’ (‘Fat Michel’) the strain of bananas which were wiped out by Panama disease in the 50s?  Well, Panama disease has mutated and returned.  It’s baaaack…and this time it destroying the once immune ‘Cavendish’ plants which make up almost every banana in Europe, Africa, and the New World Photos are becoming more and more common of dying banana plants and desperate farmers burning their groves.  ‘Cavendish’ plants are clones and if one is susceptible, they all are. I really like bananas (when they are ripe) and the idea of doing without the radioactive potassium-rich fruit makes me sad. What are we going to do?

We have the technology?

I guess a good market solution would be to make a transgenic banana that was resistant to the Panama disease, patent the critical gene fragment, and then sell sterile clones of the frankenfruit.  Since I like science and bananas (though not necessarily giant agribusinesses) so this is an acceptable solution to keep the yellow fruit on the table.

Industrial banana washing in Costa Rica

An alternate idea, however strikes me as far better.  We should send out teams of banana farmers and taste-testers to South East Asia (the first home of the banana) to collect purple, white, red, and gray bananas.  Different folks can start growing all sorts of new bananas around the world.  Undoubtedly some of them are more delicious than ‘Gros Michel” and I bet they are all more resistant to the blight.

In fact just yesterday, regular Ferrebeekeeper commenter Beatrix reported on the delicious (albeit plain-looking) bananas of Nepal. She writes:

Here in Nepal we have all sorts of different bananas growing wild & in cultivation. They vary from short sweeties to starchy plantain sorts. Nepalis don’t have names for the different types of bananas. One of the tastiest varieties here is the ugliest – it is rather small (fingerlike), sporting a mottled greenish black peel with patches of gray lichen when ripe. The peel is surprisingly paper thin but the the flesh is a rich golden yellow & the taste is the most incredible, sweet custard-y banana flavor ever. I have never tasted this type of banana anywhere but Nepal. Most Asians prefer the starchy, bland bananas that most westerners would consider unripe – they think by the time a banana gets to the yellow mottled with brown stage it’s rotten.

Who here doesn’t want to try these delicious ugly bananas?  I am ready to pack up and head off to Nepal just to try them!  What we have is a marketing problem.  If these charlatans can sell people on stuff like organic food and bottled water, why can’t they sell delicious (but ugly) finger-length bananas?  The second coming of Panama disease needn’t spell the end of bananas (although we may lose the familiar bright yellow “Cavendish”)—perhaps this could be the beginning of a glorious new era of multicolor bananas of all sizes and flavors!

Or we could use technology and modern farm techniques to make some crazy bananas!

The Undead

Lord Soth’s Charge (Keith Parkinson)

To finish up this week’s undead theme, I was going to write about another classic undead monster–I have here a long list of mummies, banshees, ghouls, and vampires from around the world (including some flying intestine-head things from Southeast Asia that would cause the most jaded horror enthusiast to cower in dismay).  However, to tell the truth, all the endless moaning and lurking in tombs and insatiably thirsting for life energy is starting to wear on me.   What is the bigger meaning of all of this?  What is it that makes the undead so beguiling to so many different cultures—and yet so oddly uniform in basic motivation and temperament?

Let’s start with the obvious emotional context of the undead.  The concept packages some pretty blatant implications right out front.   The undead represent many of our fears about sexuality—they are always biting necks, wearing diaphanous robes, or grabbing at milkmaids in the night.  They seem sexy and powerful, but turn out to be, at best, all gross and squishy (and, at worst, morally repugnant and dangerous).  The concept that one is infected by a demon-thing to then become a demon-thing oneself also overtly symbolizes all sorts of anxieties about disease and promiscuity.   I’m not going to dwell on this because I left it as an undercurrent in my four earlier essays (and because my parents read my blog), but it segues to an even bigger theme: the undead represent the frustrations of being corporeal.

We have physical bodies which provide for ephemeral pleasures but ultimately rot and fall apart.  Such frailty is a far cry from the platonic perfection which religions promise.  We fear illness and mortality, and we fear the slow failures of senescence.  What could represent that better than a living corpse?  The obsolete hopping vampire is not just wearing outdated threads from the last season but from the last millennium!  Our infatuation with all these blood-drinking spirits, revenants, living corpses, and pale walkers comes from our existential obsession with understanding death—the ultimate taboo and the greatest mystery—“the undiscovered country from whose bourn no traveler returns”.

Death the Maiden (Marianne Stokes)

So our fascination with the undead is a reflection of our fear of death.  This is hardly an original or startling conclusion.  But it only half of the full picture: the more important moral behind the living dead is also more subtle.

The undead hunger for life but they can only imitate life’s most weary habits.  The draugr is like the average investment banker, fiercely gathering treasure even after wealth has lost any meaningful value.  The lemures can not forsake the street-side shadows which they haunted in life as footpads.  Vampires are out there in nightclubs (or high schools!) picking up pretty girls with low self-esteem for centuries–when any sane person is driven to despair by the singles scene almost immediately.  Like the bloated & forgetful alcoholic returning to the same bar-stool, or the gambler driven back to the slots after recursive nights of bitter loss, the undead are creatures of dreadful mindless habit.  This is the great lesson from all these horror tropes.

Skeletons Warming Themselves (James Ensor, 1889, oil on canvas)

The undead are not beguiling; instead they are trapped like weary wage slaves going through the motions.   Our fascination with ghosts and zombies stems in part from our terror of the grave–for life is indeed very short—but the true lesson to be had from these sad legions of supernatural clichés is not to be afraid of life.  Don’t allow yourself to be captured in a stupid rut.  Life is for living, not for walking in circles with your arms out while you moan.  Get up from the opium den floor, walk out of your cubicle, flee your damn stupid pyramid scheme.  It’s time to change your loveless marriage!

Haunted Couple; Illustration from The Bridge of Love-dreams (Hokusai, 1809, woodblock print)

Live mindful of death, opportunity flees away.  Once you are really in the grave, the vampire’s bite, the draugr’s gold, all the suffering and cannibalism and exploitation and desire and hope of this world—it will all be meaningless.  In the meantime, there is no reason to act dead until you really are.

Detail from a Roman Sarcophagus

Dutch Elm Disease

Treaty of Penn with Indians (Benjamin West, 1772, oil on canvas) shows Penn treating with the Delaware under under the great elm at Shackamaxon

Elm trees (genus Ulmus, family Ulmaceae) are deciduous and semi-deciduous trees which come in all sorts of shapes and sizes.  They first evolved 40 million years ago in central Asia, and since then they have spread around the entire northern hemisphere, even crossing the equator in the rain forests of Indonesia–and that is just the natural distribution of these trees. During the eighteenth and nineteenth century elm-loving gardeners took the plants elsewhere on the globe, particularly Australia, which is now renowned for its avenues of elms. But the pinnacle of elms was in America: the American elm is a particularly large and beautiful member of the family capable of growing 50 meters (130 feet) high and 40 meters (120 feet) wide in almost any soil.  The American elm’s tapering curve caused avenues of the trees to look like gothic vaults. Many of North America’s streets used to be huge 100 foot tall glowing green cathedrals made of living elm.

Elm-lined streets before and after Dutch Elm disease

The use of the past tense has probably warned you that there is a horror movie twist to this story. Alas, in 1928, a shipment of logs from The Netherlands destined for use as veneer in the Ohio furniture industry arrived in America.  The logs carried elm bark beetles which in turn carried ascomycete microfungi. It was the American beginning of Dutch elm disease, a blight which later wiped out millions of trees. Various different species of bark beetle are capable of transmitting closely related microfungi (namely Ophiostoma ulmi, Ophiostoma himal-ulmi, and the virulent Ophiostoma novo-ulmi).  These fungi seem to be able to hybridize with one another and form new strains…with new strengths.  The fungi apparently hail from China, but their province is unclear—at some point the trail goes cold (although Chinese species of elm seem resistant to the blight). Whatever the case, European and American elm trees were not ready for the spores.  Even with heavy use of pesticide, fungicide, and aggressive quarantines, the great elm populations of Western Europe and North America dwindled to a fraction of what they were in the beginning of the twentieth century.

Life Cycle of Ophiostoma ulmi

Dutch elm disease is its own special horror if you are a lover of trees (which I imagine you are if you are reading this blog), but there is a darker terror lurking behind the blight.  Dutch elm disease is one of the most famous blights of our era in North America so far, but it is by no means the only one.  Merriam Webster defines a blight as “(a) a disease or injury of plants marked by the formation of lesions, withering, and death of parts; or (b) an organism (as an insect or a fungus) that causes blights.” These blights are spreading and multiplying.  There is an oak blight, a bean blight, and a tomato blight. There are invasive tent caterpillars, mites, and galls. Although blights are technically defined as destroyers of plants, there are worrisome parallels in the world of animals. Frogs around the world have been dwindling from an exotic amphibian fungus. Bats in the northeast cannot hibernate thanks to a different fungus and they expire of energy loss.  And the fungi are not the only worrying players.  Everyone has followed the mass die-offs of honeybees from mites and who knows what else. The mixed-up super-fast dynamics of our human world mean that all sorts of critters, weeds, bugs, bacteria, protists, spores, and viruses end up traveling all over the place.  How long till a Dutch elm disease type plague strikes some life form we hold even more dearly?

Before I creep anyone out too much by writing in this vein, it is instructive to look back at the fossil record of elms. This is not the first great die-back for the trees.  According to pollen samples taken from ancient bogs, six thousand years ago, during the mid-Holocene period, all elm trees suddenly died back close to extinction in northwest Europe.  To a lesser extent the same thing happened again 3000 years ago.  It is possible that elm tree already establishing immunities to the current blights.  As I mentioned before, most Asian species are at least somewhat resistant to the fungus, and certain individuals and cultivars of once-common European and American Elms are gradually being discovered.  Our grandchildren might once again live on streets that are green cathedrals…