Balance in the Garden: Digger Wasp

Ammophila procera on Bidens alba
Ammophila procera on Bidens alba

Activity is starting to heat up in my garden as the blistering heat of August in Florida cools down. August is generally a quieter month for wildlife activity as everyone hunkers down to take a time out…rather like winter break up north when it gets to cold to do anything.

With September upon us, there is a dizzying flurry of pollinators flitting here and there. I noticed a rather slim “something” envelop a bloom of the Bidens alba. It had long lanky legs and I thought perhaps some sort of mantid or grasshopper as it seemed to climb from flower to flower. Of course the coloring was all wrong for those types of insects, so I was intrigued to find out who my new visitor was.

The silver markings on the side help determine the species of wasp
The silver markings on the side help determine the species of wasp

Lo’ and behold, as I crept closer I saw this Sphecid Wasp drinking in the sweet elixir of my favorite Florida native wildflower. I had seen this type of wasp in the past, but not often enough to be able to put a name to it. A check of my resources and I learned it is Ammophila procera, a Thread-waisted Wasp. Given that skinny midsection, aptly named.

This particular species is one of the “digger” wasps, so-called because they dig tunnels into the ground to nest. As I’ve reported in the past, I’ve encountered similar species watching in awe as a Great Golden Digger Wasp (Sphex ichneumoneus) dragged it’s large katydid prey below ground.

My latest wasp visitor uses caterpillars as the host for its larvae. Now, before you get in a tizzy worrying about your precious butterfly caterpillars, don’t be alarmed. This species has a taste for moths with documented use of White-dotted Prominent (Nadata gibbosa), Variable Oakleaf Caterpillar Moth (Lochmaeus manteo) and one that I find at my place, the Morning-glory Prominent Moth (Schizura ipomoeae).

Here's a photo of one of the host caterpillars munching on my Eastern Redbud (Cercis canadensis) (from 2010)
Here’s a photo of one of the host caterpillars munching on my Florida Native Eastern Redbud Sapling (Cercis canadensis) (from 2010)

These species of caterpillars are often considered “pests” because they defoliate trees. Keep in mind that each insect has a roll to play in the big scheme of things but most humans will agree it is a lot easier to accept the disappearance of caterpillar that ultimately is somewhat dull in the color department as an adult over seeing a chunky monarch caterpillar disappear.

It was fascinating to read about the Thread-Waisted Wasps nest building habits. They drag their paralyzed bounty backward into the tunnel, laying an egg on a particular segment of the host. Interestingly enough, they make provisions for temporary closure of the entrance if they need to leave briefly, with anecdotal evidence of the use of pebbles, sand spurs, an acorn and even a rabbit pellet as a entry plug.

From a few years back, same species seeking nectar from Florida Native Plant Winged Loosestrife (Lythrum alatum var. lanceolatum)
From a few years back, same wasp species seeking nectar from Florida Native Plant Winged Loosestrife (Lythrum alatum var. lanceolatum)

The wasp seals it up permanently when everything is in order to her satisfaction. This part of the lifecycle takes approximately 33 days over all: eggs hatch in 2 days, larval feed and spin a cocoon after 5 days and the adult emerges 26 days later.

Even more fascinating was a time lapse video I found of the nest provisioning procedure.

Since solitary wasps aren’t necessarily aggressive, welcome them and appreciate their important mission to pollinate and practice chemical free biocontrol in your own beautiful wildlife garden.


Dick Walton

Observations on the Nesting Behavior of Digger Wasps of the Genus Ammophila
Howard E. Evans
American Midland Naturalist
Vol. 62, No. 2 (Oct., 1959) , pp. 449-473
Published by: The University of Notre Dame
Stable URL:

Title: Additions to the Knowledge of the Nesting Behavior of North American Ammophila (Hymenoptera: Sphecidae)
Author(s): Jerry A. Powell
Source: Journal of the Kansas Entomological Society, Vol. 37, No. 3 (Jul., 1964), pp. 240-258
Stable URL:


6 thoughts on “Balance in the Garden: Digger Wasp”

  1. Another good read! Thanks for educating me on facts I never have time to research! I do love your writing style!!! Hope you enjoy the cooler month of September!

    Liked by 1 person

  2. Fascinating! I’d seen ine of these characters dragging a wolf spider off.. Not used to seeing a spidey as vanquished prey! I did not know thst it would provide a hatchery.. Your research is always excellent Loret. You are a true citizen scientist!

    Liked by 1 person

    1. Hi Cindy!

      I’m learning as I go and loving it. I have seen spider wasps drag off big spiders and I find it so interesting that each species has specific host choices, just like those who feed on specific plants. Who knew? Nature continues to amaze me and provide the best entertainment!


  3. The wasps are out in full force up here. I have my grape jelly and oranges out for the Orioles. The wasps are devouring my oriole food. But they do fly away when the orioles fly in. I’m even finding dead wasps INSIDE the oriole nectar feeder and the hummingbird feeder. They are totally out of control! Fortunately I haven’t found any nests …YET!!
    Enjoyed your article.

    Liked by 1 person

    1. The wasps probably died happily overindulging in the free sweets. Those that are smart enough to fly off know that THEY are oriole food. Probably yellowjackets….not my favorite critter because they are aggressive. I like the nice quiet solitary wasps like my thin waist buddy here. Thanks for stopping by my friend. 🙂


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s