When I started making my garden more wildlife-friendly a couple of years ago, I never dreamed that wasps would be among my favorite visitors. Since then, I have caught a glimpse of the fantastic diversity of wasps that will appear when welcomed into the garden, and have begun to appreciate how beautiful, interesting and charming they can be. An endearing example appeared last year at the end of August.
Last year was a hot, dry summer here in Portland (once summer finally arrived), and although my garden is fairly drought tolerant, I had to water it occasionally. The day after one of those irrigations, August 22North DakotaI saw a fierce looking wasp staring at a patch of wet dirt near my old rock wall. It was about an inch long. It had a jet black body dotted with yellow and orange wings and a long, incredibly thin waist. she was Sceliphron caementariuma yellow-legged mud-painting wasp, and boy, was I happy to have found some moist soil in this parched land.
Photo by Hectonic
The yellow-footed mud dauber is a common species throughout much of North America. You may have come across their nests under the eaves of buildings or in other sheltered places. Single mothers build these structures out of mud for their children; They fill the cells with several paralyzed spiders and lay an egg in each pile of supplies. At the end of the season, the mother will die, but if all goes well, her offspring will eat the spiders and emerge as adults the following year to mate and repeat the cycle.
My husband called our guest Pam (Pam Dauber) and, for the next two weeks, I watched as Pam returned to the mud patch, which I kept moist for her. I saw it at least six more times. I was able to observe it closely without fear of being stung. Solitary wasps, which make up the vast majority of wasp species we are likely to encounter, are friendly and rarely sting humans. The males do not have any stinger and the females only want to bite their spiders and insect prey so they can feed their children. They have no problems with humans.
Pam was an efficient worker. Upon arrival, he quickly walked through the patch of mud in search of the perfect consistency of the soil. Once he had concentrated on a spot, he would lower his head and dig. It made a high-pitched, happy hum as it dug.
His body leaned forward until he was in a handstand. When he righted himself, I briefly caught a glimpse of the smooth, shiny ball of mud, no bigger than a ball, tucked under his chin and held there with his front paws and jaws. In an instant, she was gone, flying over the house and across the street with her prize. I didn’t know where its nest was, but it couldn’t be far away. One day I timed it and it took less than two minutes on average to get to the job site, do the masonry, and return for more materials. He worked hard and took few breaks.
In his magnificent book titled Wasps (Pollination Press: 2021), biologist extraordinaire Heather Holm explains what Pam was probably doing while she was across the street. It probably took up to forty loads of clay to create each cylindrical nursery cell, completing one cell in two hours or less. After building several cells side by side and supplying them with eggs and spiders, he probably collected more mud to cover the entire structure and reinforce the walls.
In the section on clay painters of his book, Holm references a very old book on wasps with more information about these fascinating creatures. I downloaded it (it’s so old it’s in the public domain) and quickly devoured it. George and Elizabeth Peckham published On the instincts and habits of solitary wasps in 1898, but the information is still relevant today and the writing is delightful. The book details the couple’s studies of the life cycles of many groups of solitary wasps on a property in Wisconsin. I find the idea of a husband-and-wife team of Victorian-era biologists studying insects together adorable. And, man, did they go crazy? They sat for hours in the hot sun with their eyes glued to wasp nests, chased insects across fields, performed countless experiments, and took copious notes. In the chapter on mud daubers, they report that they opened 573 nursery cells and content cataloging.
One interesting thing the Peckhams emphasize in their book is that even within a species, wasps are individuals, each a little different in their behaviors and abilities. They say this is especially true among mud daubers. They use different types of mud in their nests, they vary their architecture, they capture different species of spiders, they make different numbers of cells. They vary in their athleticism, craftsmanship, and hunting skills.
Reading this past winter made me wonder: how did Pam fare in these domains? Was she a good builder? What was your house like? Was she a good mother? How many babies did you have? How many spiders did you catch? I had seen her hunting one day, but I didn’t see her catch anything. Would you be able to protect your nursery from winter rains? Would my granular soil hold up? Would humans near its nest freak out when they saw it and tear it down out of ignorance and fear?
I thought a lot about that last question.
I could only hope that on a sunny day the following summer, a new black and gold wasp with tawny orange wings and an impossibly thin waist would enter the garden. She let me know that the children were fine. Pam’s daughter would be eager to start building a house and raising a family of her own, and I would have to get the mud ready.
I already had the mud ready. Last summer, I turned a Sweet Basil Thai takeout container into a mud collecting station. I filled it with soil and dipped it into my garden pond every morning so the mud would stay wet all day. Having the container near the pond made it easier for me to keep the soil moist. I hoped the wasps would find it easy to find it there too, since near a pond is the logical place to look for mud. And I had no doubt that Pam’s daughters would be logical and astute people.
I wasn’t wrong. In late June, Pam’s daughters, or at least the wasps that were the spitting image of Pam, began to appear.
By the end of July, at least four or five mud daubers were visiting my takeout tray regularly. On the warmer, sunnier days, it was like LaGuardia in there. Watching wasps at work became my new summer hobby.
He also often saw them prowling the garden, hunting for spiders or drinking nectar from flowers to fuel their busy bodies.
A couple of times I even saw another wasp in the clay tray…tripoxylon. It is a smaller, completely black wasp that also uses mud to build its nest and hunts spiders for its young.
I once saw Eumenes Also use the mud tray. I’ve seen these yellow and black potter wasps in the garden, hunting for caterpillars, but I’m still hoping to find one of their nests, which look like miniature clay jugs. Next year, I will remove the mud in the spring for the mason bees to use as well.
Who knew a humble lump of clay could be such an attractive garden asset and a great source of entertainment?
