When I started teaching at Merritt College, I was “given” the Environmental Center property as a place to hold my labs - basically, as a place to grow a garden. In years past, it had been used for that purpose (though, I would argue, not to its full potential), and even held a few remnants of the old raised beds. But it had long been abandoned and unused; my co-workers had several truckloads of junk and trash hauled away, which revealed a rather shabby and sad space. The ground was either rocky, or covered in weeds. The outbuildings were mostly being taken over by nature, with mushrooms growing out of roof tiles and critters nesting in walls. Invasive Himalayan blackberry vines covered every corner. The first lab I held there, I had the students spend an hour just being in the space, mapping it out, taking an inventory of what was there, noting how the sun might move across the sky, how the wind moved through the space, and what they thought could be done with the property to make it a ‘real’ farm. On that day, I watched them move through what would eventually become our garden, and took my own inventory of the space. And I realized something that day. I realized that there were no bugs.
A female (identified by the curled antennae) tarantula hawk-wasp taking a break in the Environmental Center garden, on my newly formed paths
Actually, no birds either, except one curious scrub jay. No scuttling lizards. Nothing zooming past, not even a pesky fly. Now, sure, it was late January, but that’s no deterrent in coastal California. If it’s above 50 degrees (and it was, that day, as it is nearly every day of the year in Oakland), bugs are generally out getting some stuff done. But not at the Environmental Center.
My feeling was that the space had been abandoned so long, and was so full of invasive (rather than native) plants, and was so crowded with non-flowering weeds (mostly exotic grasses), that nothing really wanted to live there. This is not an uncommon thing. Urban spaces are increasing across the globe, destroying valuable habitat for all kinds of creatures. How can an insect live in a place with only concrete, glass, and steel? Urban spaces not only lack flowering plants, they also often devoid of any kind of slow-moving water, crucial for drinking but also for many insect nurseries. Cities trap heat to become even hotter than their surroundings, becoming ‘urban heat islands,’ uninhabitable to many species. Vehicles rush around, creating dangerous circumstances for any surviving insect just trying to get from here to there. And people are fearful of insects, generally, and are quick to squash and kill anything they don’t understand.
As I’m sure you’ve heard, insects are absolutely vital to our human lives. Not only do they provide pollination services, they are a critical food source for so many animals that live further up the food chain. Many, like wasps, are also important biological controls, keeping a check on other insects, feeding them to their young. And others, including yellow jackets, are valuable detritivores, cleaning up dead animals and other organic matter so that we are not buried in refuse.
A common blue mud-dauber wasp dragging a spider to its nest to feed its larvae, at the Environmental Center
I know that over the (almost) ten years I’ve been writing this blog, I’ve given some mixed messages regarding pests. I have used yellow jacket traps in the past. I mean, yellow jackets are annoying as hell, there’s no question about that. Eating outdoors is one of the absolute joys of summer, and some yellow jackets make that next to impossible. They also bug my chickens and my honeybees, which I don’t like. So for many years, I rationalized my trapping, until I started to read more about general insect decline and the way that decline affects us. (By the way, if this is something you’re interested in learning more about, I’d recommend checking out Dr. Dave Goulson, or Dr. Doug Tallamy.) Now, I make it a practice not to kill any insect on purpose, and rather to learn as much about them as I can. I find that when I learn more about something, I become fascinated with it, and that in turn leads me to appreciate it fully.
This point was driven home to me when my folks shared that they’d recently read an article in the Wall Street Journal about how beneficial yellow jackets really are. I had been talking about insects in a positive light for years, but it wasn’t until my parents read an article for themselves that they had greater fascination for the subject. This made me realize that, though I’ve written on this subject before (here, and here and here, among others) it really bears writing about again.
There are several different kinds of yellow jacket wasps in California. They are generally either in the Vespula or Dolicovespula genera. Some nest in the ground, in old rodent burrows, and some nest in walls or trees; some that are strictly insect-and-nectar eaters, and some which are scavengers. The scavengers are the ones that annoy us at picnics. They are also the ones who generally will enter a trap. However, the others are great for ecosystem health, and deserve our respect and admiration.
A yellow jacket pollinating at Poppy Corners
And there are many other interesting wasps, such as the ones in the photos near the top of this post. Many wasps, such as the tarantula hawk-wasp and the common blue mud dauber wasp, take other bugs home to their nests to feed their young. The tarantula hawk-wasp, for instance, stings a tarantula between the legs (!) and drags it back to the nest, where it then lays one egg on the spider, takes pains to keep the spider alive until the egg hatches into a larva, which then feeds on the living spider until it pupates. I mean, the stuff of nightmares, yes? And yet also intriguing. Other predatory wasps do this with the very caterpillars that threaten to eat our crops.
In fact, in a 2021 study by the University of London, it was shown that “predation by insects -- as biocontrol to protect crops -- is worth at least $416 billion (US) per year worldwide,” and that wasps actually regulate populations of agricultural insects. This is a priceless service.
Another priceless service that wasps perform is pollination. Many wasps use nectar for their primary source of daily energy (the ‘meat’ is for larval development only), and the study states, “pollination by insects is vital for agriculture, and its economic importance has been valued at greater than $250 billion (US) per year worldwide.” These are not small numbers. Our food supply is already under threat, for oh so many reasons - so let’s use any and all of the free ecosystem services that nature provides us, shall we?
an old paper wasp nest in the eaves of our train shed at Poppy Corners
With all of these services firmly in mind, at the Environmental Center, one of the first jobs I gave the students was to plant a pollinator garden. I had obtained a grant for seed from Pollinator Partnership, and they sent us a large bag of various native California wildflower seeds. We knew that our vegetable and fruit plantings would attract pollinators, but we wanted to ensure as much diversity as possible, and that seed grant gave us another 30 species of flowers with which to attract and feed insects. (Also deer, but that’s a story for another time.) And once the goldfields started coming up, and the tidy tips, then the gilia and the poppies, the bugs started arriving - hover flies came first, then honeybees, then butterflies, and finally now, on these hot summer days, I’m finally seeing the wasps. I’m delighted. Now that there is the buzzing and zooming in the air, I’m starting to see lizards, and skinks, and snakes. Birds of all kinds have found us. Each of these species brings a new set of challenges, but that’s ok - we know that having a healthy ecosystem brings far more benefits than it does problems.
As the garden evolves, my plans for it does, too. I intend, this fall, to have one class build an herb spiral and plant fruit bushes and trees, which will attract even more pollinators. Another class is going to create a garden full of traditional, cultural crops, which should bring in even more native insects. I look forward to seeing the ecosystem develop and create a closed loop, where everything within the loop thrives, including the humans who eat the food grown there.