The other day I was trying to explain how fig trees work. It is insanely complicated.

I don’t mean the many horticultural varieties of figs people grow in their yards, like the ones pictured above, seen recently on a garage parking lot on Union Street. These develop without pollination; they are parthenocarpic. I mean the figs grown commercially in California and known as Calimyrna (they are thought to have originated in Smyrna, now Izmir, Turkey). These figs, Ficus carica to the botanists, only come about because of the tiny wasps, Blastophaga psenes — imported from Turkey like the trees — that pollinate them. But let me back up: the fig fruit itself is not exactly a fruit; it is a synconium, a kind of multiple fruit, full of flowers which become seeds when pollinated. Those little crunches you crunch in a fig are the achenes, the hard coating around the seeds. Think of it as closed-up sunflower, or hundreds of tiny little fruits in one delicious package. For these to pollinate, a wasp must crawl into the synconium, losing her wings as she squeezes through the tight passage; it’s a one-way trip. You end up eating her remains, but don’t worry, vegetarians, she’s been broken down by ficin, a protein-digesting enzyme.

Before this doom, she emerges out of an inedible fig from a male tree (Calimyrna farmers, de facto wasp wranglers, have to have both female trees, which produce edible synconia, and male trees, which produce inedible gall figs) where she was born and where she has mated with a blind, wingless male wasp (he never leaves the male fig). As she exits the inedible male fig, she picks up pollen. Pollen-smeared, egg-laden, she may enter either a male or female fig; but her ovipositor is too short to reach into the long-styled female flowers, so she can’t lay eggs in those. She does pollinate them, sacrificing her life for Fig Newtons. Meanwhile, if she finds her way into a male fig, she will deposit her fertilized eggs. And around it goes again. Fig farmers separate the trees to control the amount of fertilization; there’s the potential of the synconia bursting if too many wasps get inside.

It used to be said that there was probably a separate wasp species for each of the 800 known fig species, although we now think some of the wasp species pollinate more than one species of fig. To be clear: these fig species are mostly tropical and inedible (to us, but may anchor whole food-webs for other species). By the way, there are also individual species of parasitic wasps that prey on individual fig wasp species…

The picture below is from an organic market in Florence several Septembers ago, showing the varieties of local edible figs:“First Fig” by Edna St. Vicent Millay:
My candle burns at both ends;
It will not last the night;
But ah, my foes, and oh, my friends—
It gives a lovely light.

6 Responses to “Figs”

  1. 1 Charlie Breunig July 14, 2011 at 2:48 pm

    THE QUEEN OF TREES is a great PBS documentary on fig trees and fig wasps. Amazing photography.

  2. 3 Nora charters July 17, 2011 at 3:42 am

    No way!!!! I love a nice fig newton. A wasp?

  3. 5 Diane Moffat September 5, 2013 at 3:34 pm

    excellent information!!!

  1. 1 Tree Omnibus | Backyard and Beyond Trackback on January 7, 2018 at 8:01 am

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