Vanishing Act

Unlike some of those indoor folk who want to spray high and low for “bugs”, fruit tree growers have an appreciation of the insect life around us. We know that pollinators are essential to the production of many fruits, and that predator insects and spiders are our allies in the control of pest insects. But like everything else in the biosphere, insects and other invertebrates are feeling the effects of us humans. And it's not pretty.

Yale University's environment360 is not a gloom-and-doom publication, but in a recent article there,  Vanishing Act: Why Insects Are Declining and Why It Matters, journalist Christian Schwägerl reports on the astounding decline of invertebrate populations around the world. Of course bee populations have been getting most all of the press coverage, but the decline is massive and widespread. A few examples:

--- Since 1989, the average biomass of insects caught in field traps set by researchers in Germany has declined from 1.6 kilograms to just 300 grams.

--- German scientists have also observed a decline in butterfly and Burnet moth species from 117 in 1840 to 71 in 2013, in a Bavarian nature reserve.

--- Stanford researchers have calculated a 45 percent decline--- yes, almost half--- in global invertebrate populations in just the past 40 years.

Can anyone out there not guess the causes?

--- Pesticide use. Yes, pesticides work. They kill insects. Lots and lots of them.

--- Monocultures. Agricultural monocultures are “biological deserts”, supporting far less invertebrate life.

--- Habitat loss. Urban development, wetland destruction, deforestation, pollution, and other damage and loss of wild terrain simply leave a lot fewer places for invertebrates to live.

The first rule of ecology is that everything is connected to everything else. The decline in insect populations produces a corresponding decline in species that feed on insects, notably many bird species, bats, and amphibians. And in the species that feed on these, and so on. And disrupts plant populations, and the species that feed on plants. And on and on.

Polar bears, otters, and other “charismatic” species make good press to call attention to our impact on our fellow creatures, but those uncuddly six and eight-legged ones may be more important. Scientists are ramping up efforts to monitor populations and to find ways to slow the decline, but no one knows where all this is heading, or where it ends up. Let's hope it's not a world without butterflies.

Best Mango Ever?

Mangos--- unlike, say, black sapotes--- have wide variation in flavor, texture, color, and the other subtle elements that go into the tasting experience. With so many different ways to weight these elements, combined with horticultural factors such as ripeness, fertilization, weather, and so on, it's hopeless to argue over which mango tastes best. Of course, that doesn't stop the folks at Tropical Fruit Forum--- or anywhere that mango lovers may gather--- from trying.

With 26 mango varieties on my property and room for a couple more down the road, I've burned up more than one afternoon poring through the TFF discussions. The mangos produced by the Zill nursery in Boynton Beach receive a lot of attention. And with good reason, as they are among the most innovative of the new varieties appearing on the market.

Most readers rank two of the Zill creations at or near the top--- Lemon Zest and Sweet Tart. The latter is a seedling of the “ZINC” mango--- the Zill Indo-Chinese. For eating pleasure, Sweet Tart gets astounding reviews from the tough crowd at TFF. Some of them verge on the mystical:

Brett Borders: The inside flesh was succulent & dark orange. It reminded me why I love tropical fruit--- because of those rare experiences where you taste something so appealing that it seems unlikely it could grow from a natural seed in the ground. Where you wonder if it might have somehow been genetically altered or contain alien DNA?

This mango has a magnificent sweetness that outshines candy & cane sugar... with a musky cantaloupe-like undertone and a bold tartness that tingled and tickled my mouth. Some cola syrup was under the skin and most concentrated near the stem. I tried to slow down and enjoy each bite... but I staggered and could... not... stop... until all that remained were some paper thin strips of skin and a very clean seed. I rate this mango as "outstanding" - a wonder of nature and agriculture.

DurianLover: You bite few times, and than you stop and think. What's going on here? There are explosions of sweet, acid, and tart. Tart being most prominent flavor. Sometimes I think I don't like this mango. Too much tart. But than I would change my mind one minute later, and think this is an awesome mango! I guess its just one of the tricks this mango plays with your mind. Some people never get used to strong tart component, so you have to try for yourself. If you like it, than you really going to like this mango. Also its the only mango you taste long after last bite. For this reason at one point I made a habit to finish every mango meal with ST.

jc: If you want mild, laid back, subtle nuances of flavor and aroma this fruit ain't for you! Sweet Tart mangos will make your mouth water uncontrollably, and not in a negative sense. If I only had space for two mangos one would be the Lemon Zest and the other would be the Sweet Tart.

zands: The sweet-tart mango is the sweetest mango I have encountered. It veers into sugary so diabetics should avoid this one and I am only half joking. Yes there are some sub-acid and tart flavors underneath. The sub acid + tart component is 15% of the amount of the sweet components so if you don't like tart you don't have to worry about planting this mango tree.

bsbullie: To me [ST] is better than LZ... and while not everyone has had the opportunity to taste it yet, don't look back 'cause here comes Cotton Candy.

Squam256: I would compare it to a prime Dot if I had to compare it to another mango. It's a ZINC seedling but doesn't really taste like ZINC. Some of the ST's I've had are up there with the best mangos I've ever eaten...and I've tried hundreds of cultivars.

The tart component only dominates depending on how under-ripe it is. The more ripe it is the more richly sweet it becomes. One of the beauties of Sweet Tart is how long the window is on when it can be eaten and enjoyed.

What is the tree like? Some describe it as “compact”, while zands says: .

Sweet tart is such a heavy and precocious bearer that it will change the canopy structure of the tree and make it more spreading. Left to its own devices without producing they'll grow very vertically.

Despite its magnificent flavor, the Sweet Tart's commercial value may be limited. One of the heavy-posting pro's on the Forum reports that Sweet Tart does not ship well--- “If picked green it won't ripen properly, and if picked at the proper stage, it's too soft to ship.”

My own Sweet Tart is fairly new, planted as a 3-gallon tree just last December. Awarded a prime irrigated planting spot, it's off to a good start, with healthy-looking leaves from a couple of flushes. I won't let it fruit next year, but perhaps 2018 will make me a true believer.

Mangos, Mangos, Mangos

Yes, mango season is finally here. I long ago stripped the fruit from my younger trees, but several of the older ones are getting their first chance to fruit. Let's take a tour.

This is the only surviving fruit on the Ice Cream tree. It's a delicious variety, but most experts say it's poorly adapted to our region. If this fruit survives to maturity, it will be a good occasion for my tree to tell its interesting story.

The Glenn variety is considered one of the most reliable producers. The half-dozen on my tree are starting to show some blush.

Coconut Cream! There are only two on the tree. It's one of the varieties that don't develop much color, and this one is full size, so I'm going to harvest it now before someone else does.

This is one of the half-dozen or so fruit on the disease-resistant Mallika. Pine Island Nursery rates it a top-score 5 in every category except "color". Like many sources, they recommend picking it at the "mature green" stage and allowing it to ripen on the shelf in 10 to 14 days.

The Rosigold has actually fruited for a couple of years, and already gave some fruit from last fall's blooming. It now has several starting to show color. I picked one a couple of weeks ago, and after ripening on the shelf it was very tasty. Rosie is rather subject to anthracnose, so the fruit are not very pretty, but for home use the extended season and small tree make the Rosigold variety a good choice.

Here is this year's entire crop from my young Kent. It's supposed to be a later-season variety, but this one looked ready to pick a month before the book says. Perhaps it was just early because the tree could put all its energy into this one fruit. But down on Pine Island, friend of the MRFC Steve Cucura reports an oddly compressed mango season, with the peak coming up in the next three weeks or so. To be safe, eat lots and lots of mangos this month!

Che

This is about che--- the fruit tree Cudrania tricuspidata, not the mixed-success revolutionary. It's related to the mulberry, close enough that in China its leaves serve as a backup food for the silkworm when mulberry leaves are scarce. The sweet, round fruit is mulberry-like in form, but reported to taste quite different, with a delicious watermelon-like flavor.

No freeze tolerance worries with che--- it can handle winter temperatures below zero degrees Fahrenheit. Two traits limiting its appeal have been the three to six small seeds in each fruit, and the fact that the small, shrubby trees are dioecious--- both a male and a female are required. Now, however, there is a seedless, self-fertile variety available.

Seedling trees take up to 10 years to fruit, but che is readily grafted onto another mulberry relative, the osage orange, which also prevents suckering and produces a tree form, rather than the natural shrubby habit.








It wasn't until I looked up some images that I recognized the osage orange as a familiar tree from my youth in Ohio. This picture of its fruit by Gale French is in the Wikimedia Commons. Though its fruit is inedible, the osage orange is an interesting tree worth an article of its own. The seeds are edible, though said to be difficult to obtain, and the dense wood has the highest BTU content of any North American fuel wood.

This spring I obtained my seedless, self-fertile che from master grafter Wayne Clifton. It's joined my three persimmon trees in a sunny area, not irrigated but well-mulched. If the fruit is a tasty as I expect, the che's small size, hardiness and beautiful foliage make it an attractive edible landscaping choice.

Magnificent Seven Update

Back in March, I wrote about how Josh and I dug a big hole in the ground, and filled it with chopped-up banana plants and other compostable matter, and put some of the soil in a mound that partially encircles the hole, and added topsoil and manure onto the mound, and covered the whole thing with a thick layer of mulch from local tree crews. And about how when spring came, I planted seven small papayas on the mound, and staked them well so that the ring-tailed forest gods couldn't trample them on their nightly rounds.

What a difference three months can make! The middle three in this family portrait are Sunrise, one of the major commercial varieties in Hawaii. The tallest stands at least eight feet and already sports more than a dozen fruit. The right-hand two were sold as “from seeds from Costa Rica”. The two on the left are the rare broadleaf variety, grown from seeds that I got from Berto Silva when he spoke to the MRFC last year.

Here's the trunk on the largest Sunrise--- no need for staking now! Sunrise is known to be a tall, fast grower that produces relatively small-sized fruit. Given my healthy aversion to ladders, a tall variety was not a wise choice. But to look on the bright side, one of these days I'll get to write about techniques for topping papaya plants.

The Costa Ricans are slower-growing, and to this point only one carries a fruit. So far they look like ordinary papaya plants.

It's difficult to find much information about the broadleaf papayas. As best I can determine from online sources, they are a variety of the standard species, Carica papaya. Daley's in Australia touts the fruit  and says that only female and hermaphrodite specimens have been found. Several in the gang at Tropical Fruit Forum report that it's a slow grower, but though mine can't match the vigorous Sunrise, they are keeping up with the Costa Ricans. Some specimens have red petioles, but mine have only a reddish tinge. Unless Berto was very, very careful, mine could be outcrossings with ordinary varieties, but who knows?

Friends tell me that unprotected papayas sometimes end up with worms and sometimes not. I'll see how the unprotected fruits of each variety turn out, but I'm also trying some nylon bags from the Territorial Seed Company. They are fairly inexpensive and very easy to use. I'll let you know whether they actually work.

With any luck, I'll be able to report taste tests on these three varieties.

Bad Apple

A tip of the hat to Jeanie Glass for the link to this recent article by Dan Nosowitz about the deadly manchineel tree, Hippomane mancinella.

The manchineel grows in Florida, and according to IFAS it's usually a tall shrub found along seacoasts and in brackish swamps where it grows among mangroves. As you can see in this photo by Hans Hillewaert at the Wikimedia Commons, the fruit of the manchineel looks something like a small green apple, giving rise to its totally inappropriate common name of beach apple.

The fruit actually has a sweet, pleasant taste, but it and the entire tree are violently poisonous:

---The sap can cause burn-like blisters on the skin.

---Smoke from the burning wood can injure the eyes.

---Radiologist Nikola Strickland gave this description of taking one bite of the fruit:

[Moments later,] we noticed a strange peppery feeling in our mouths, which gradually progressed to a burning, tearing sensation and tightness of the throat. The symptoms worsened over a couple of hours until we could barely swallow solid food because of the excruciating pain and the feeling of a huge obstructing pharyngeal lump. Sadly, the pain was exacerbated by most alcoholic beverages, although mildly appeased by piña coladas, but more so by milk alone.

Over the next eight hours our oral symptoms slowly began to subside, but our cervical lymph nodes became very tender and easily palpable. Recounting our experience to the locals elicited frank horror and incredulity, such was the fruit's poisonous reputation.

Not surprisingly, native people used the sap to tip poisoned arrows, and legend has it that one of these ended the life of Spanish explorer Juan Ponce de León.

The manchineel is apparently toxic to all mammals, but healthy fare for iguanas. And the wood, aged until the sap has lost its potency, is used in cabinetry.

As mentioned Nosowitz's article, the manchineel is a relative of the familiar (and also poisonous) poinsettia plant. While the manchineel can claim to be the most deadly tree, there are even more dangerous plants even here in Florida. A quarter inch of the stem of the spotted water hemlock Cicuta maculata can be fatal.

It deepens my appreciation of the ability of wild creatures to figure out what to eat, without the help of tribal knowledge or smartphones.

To Fest Or Not To Fest

The annual Fairchild Mango Festival is only a few weeks off. One of my acquaintances, Hammy (is that short for Hamilton?), has been thinking about going. He's a bit of an odd fellow--- claims to be descended from Danish royalty--- and he seems to have a lot of trouble making decisions. Called me up the other day to tell me about his deliberations. As I recall, it went something like this:

To fest or not to fest, that is the question
For each year's Fairchild mango celebration.
Whether 'tis nobler in the mind to suffer
The heat and crowds of peerless mango show
Or stay at home in air-conditioned bliss,
And down a couple cold ones. South to drive
No more, and in our comfy home forget
The steam bath, and the thousand stinging bugs
That flesh is heir to. 'Tis a recreation
Gladly to forswear. To rest, to sleep
Perchance to dream of unknown mango kind
Of taste supreme. Ay, there's the rub.
For those exotic mangos that we'll miss
By passing up Sir Richard Campbell's bash
Must give us pause. Such is the fear
That keeps us going back each year.

(with deep apologies to William Shakespeare)