Jan 9, 2014

Alien in the garden

While watering our summer garden I spotted this on one of our tomato plants. I hollered for Oyon to come see his classroom science lesson come to life. I thought I'd found the butterfly eggs he'd been diligently seeking over the past few weeks.


We gleefully nosed closer for a better look then jumped back in shock. A quick web search left us gazing sadly at the poor parasitized Hornworm hanging off our plant. Seems it was hosting Wasp cocoons. And by 'hosting' I don't mean making sure the sheets were fresh, clean towels were handy and that there was something more interesting than Fruit Loops for breakfast. They were feeding the wasp larvae in the most literal sense.
Because that's what was happening to those Hornworms: they were being eaten alive from the inside. As I tried not to gag and groped to relocate my ecological sensitivity so I could reconcile to the gory wonder that was the food-chain, two further surprises (via Google) came whizzing my way:
Sphinx Moth:
The 'Hummingbird' that had delighted us earlier in the summer by hovering next to Oyon's right ear for a few seconds was more likely a Hummingbird MOTH. They are drawn to Butterfly Bushes (like our neighbors) but also to the Anthurium I'd planted. Some, I'd placed in the vegetable bed (to draw pollinators for our veggies) and others around our front door in planters - which is where the Moth had appeared. And what is one of the stages of a Sphinx Moth's life cycle? Hornworm! 'Curiouser and curioser' turns out be just the phrase when you're falling down this kind of rabbit hole. Lewis Carroll must've had a kitchen garden.
Braconid Wasp:
The delicate little red-winged 'flies' that we had been spotting (and admiring) outside all summer long? Turns out the only thing 'fly' about them is their preferred mode of travel. Actually Braconid Wasps, these insects hold only warmth for humans in their dear little hearts and no sting at all. They buzz around, generously pollinating to ensure that zucchini flowers turn into zucchini vegetables and constantly searching for.....Hornworm! Yes, the plot does indeed thicken here. Hornworms, doomed offspring of Sphinx Moths, are the budget motel of choice in the Braconid Wasp world. They lay their eggs (via stinger) just under the Hornworms skin and cocoons emerge in time, housing larvae that  then avail of the round-the-clock, all-you-can-eat buffet until it's time to emerge as adult wasps.
So to connect the dots: the flowers in our garden attracted pollinators that made our plants productive THEN they produced predators to destroy said produce but THEN one predator-pollinator attacked the other, interrupting both its dastardly plans and its life cycle and.....SCORE for us vegetable loving humans!!!!
It's called 'bio control' and practised mindfully as 'Integrated Pest Management' in ecologically conscious farming operation. In our garden though, it was just another awe-inspiring instance of Nature thumbing her nose at our paltry efforts to 'save' the planet as it effortlessly functions the way it has to.
Baby Braconid Wasps emerge after gestation.

Empty cocoons on a spent Hornworm.

All that remains

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