Spring is here, according to the elm buds and the tiny flying insects I see in my yard once the sun has warmed the frost. I want my yard to be alive with insects. So, I’ve planted a diversity of flora indigenous (plants native) to Appalachia and specifically East TN. I’ve also invested in a solitary bee house (a dollar at the Dollar General last year), as well as making one a bee condo. Which I must say, feels like a poor design, but ya gotta start somewhere. I have tubs for water and spray a pyrethrin-based insecticide directly at the junction between soil and tiny house; no where else. For the trees and the vegetable garden, I will add some generalist and specialist bugs to help deal with the squash borer, tree boring insects, and aphids that will want to nix my cabbage-family crops. Buggers!
My much loved neighbor, one of the strongest women I’ve met, is considering a garden this year - I like to think the one in my front yard has inspired her but probably I’m a bit full of myself;) Anyway, she and many of the students I have taught over the years, has a genuine hatred/fear of insects. “They’re disgusting.” People are complicated in beautiful ways and sometimes not so beautiful. Fear is an effective deterrent of danger and often, according to evolutionary biology, a rational response resulting in individual survival. However, we’ve become hyperbolic about insects. Without them, we are ensuring our demise. Insects and plants have evolved together for 100s of millions of years. They need each other and thus we need both as well.
If you have trepidation or full-on loathing of arthropods (insects, bugs, butterflies, spiders, etc), hopefully I can change your mind a bit? Most peeps love butterflies and colorful moths. They’re elegant and fragile. There’s a growing love of bees with an understanding of what they bring to us (their ecosystem services). With that comes also a changing perception of what is beautiful. Like the multi-faceted insect eye. Thank you close-up photography and IG photo geniuses! But how to get more people to invite the assassin bug, the soldier beetle, and the needle-wasted braconid wasps? What about those yellow-jackets and hornets that want to nest on the porch? I’m gonna give it a go…though I do agree with removing the wasp nest on the porch but do so gently. When it’s cold and they are too slow to attack, when the paper nest is small. Knock it off and take outside. Don’t spray with an insecticide that will poison you as well as the wasps.
The assassin bug is a true bug and will bite you, though I have picked them up without injury. Sheer luck or perhaps I am the bug-whisperer; dreaming. Assassin bugs are generalists feeding on any other insect, including another assassin bug but have food preferences. Their ideal buffet would include tomato hornworms, leafhoppers, aphids and other bugs injurious to vegetable and flower gardens. Attract them to the garden by planting members of the carrot family (Apiaceae) like fennel, dill, and coriander. I bought some bugs my first year with my new garden, to get them established, providing the fennel needed to foster their reproduction and keeping the leaves over the winter. Growing coriander in East TN escapes me; got suggestions please send???
The assassin bug is an “ambush predator”. Like most things in life, there are many ways to do things. Hunting can be by capturing prey in elaborate webs, searching them out through chemical trail hunting, or waiting for the devil to come to you. Assassin bugs prefer to hang-out motionless, awaiting their prey to come within arm’s reach. They’ll use a different strategy with aphids. Once found, aphids are going to offer an all-you-can-eat buffet. Perhaps the most fascinating behavior of assassins is their collection of ant carcases on their backs (see photo below from besgroup.org). The nymphal (pre-adult stage) will suck the ants dry and pile them up on their backs. This can both hide the nymph from its predators and possibly attract additional ants attracted to the scent of their dead brethren.
Who is the assassin bug afraid of? Birds and other bugs. Thus, they’re providing not only active-duty services in the garden, they’re also ensuring your birds have an important food source.
These guys, like the assassins, enjoy a ubiquitous distribution. They, too, are fond of aphids and caterpillars. I worry about my goals to attract spicebush swallowtails and am thrilled to have the aphid help. I have seen these in every garden I help manage that takes an IPM approach. Integrated Pest Management reduces pesticide inputs to a minimum and/or employs OMRI listed insecticides. Soldier beetles look an awful lot like lightning bugs (closely related); I often confuse them. I was fortunate to have a lot of goldenrod when I moved in. To deal with nematodes and provide more soldier beetle habitat, I’ve planted marigolds. To increase the number of soldier bugs and pollinators, I have added zinnias to the sunny spots.
Note, eggs and larvae (youngest mobile life-stage) overwinter in leaf litter, same with lightening bugs so if you’re seeing fewer lightening bugs - keep your leaf litter through end of February. Younger stages of some soldier beetle feed on slugs - for you hosta growers!! Other species feed on the plants recommended above, the nectar and pollen - they’re pollinators! The leatherwing pictured below can be found awaiting or hunting prey on goldenrod in late summer.
NEEDLE-WASTED OR BRACONID WASPS
I can’t say enough good things about wasps. First, their species diversity is incredible and with it, the diversity of roles they play that are integral to our success as consumers of plants. To help you fall in love with them, you might find the book The Bees in Your Backyard.
Predatory and parasitic wasps are critical in my yard because I love squash and the squash plants out here will get the darned bug that tunnels the stem leaving the plants to die from the ground-up. Heartbreak, many of you have experienced? These wasps will also parasitize tomato-hornworms (I hope to see this once in my life in the ‘flesh’), as well as tent caterpillars, aphids, and various beetles. I don’t know what it is about the carrot-family but they do attract a lot of beneficials. Need to research the lit for that attraction mechanism. Anyway, to attract these elegant helpers plant carrots, queen ann’s lace, fennel, dill as well as chamomile and feverfew. Feverfew is probably a volunteer in your yard already.
Braconid (and other wasp families) are being explored as an excellent resource for controlling forest pests. They hunt the caterpillar-like stages of many insects that consume leaves or bore into trunks of trees. There’s a tremendous diversity of species (1000s). If you’ve ever unrolled leaves to find a white cocoon next to a caterpillar, the cocoon is probably a braconid which has already parastizied the adjacent caterpillar.
There’s so much to learn about these wasps I leave it to the read to find the suggested book.
Bird Ecology Study Group
University of Kentucky Entomology
Entomophytophagy (‘Sequential predatory, then phytophagous behaviour’) in an Indian Braconid ‘parasitoid’ wasp (Hymenoptera): specialized larval morphology, biology and description of a new species. Ranjith et al. 2016. PLOS One
1. Caters News Agency
2. B. Newton 2004
3. University of Georgia