Bugs That Harm, Bugs That Help
If there is a water source nearby, dragonflies will be found in the air or perched waiting for a passing meal.
While gardens are in many respects a reflection of their gardener, they are in no way cut off from the surrounding environment. It isn’t long before herds of aphids are clinging to your prized tender shoots. Soon after, groups of ruffians take to the foliage, munching in a day what took your garden weeks to grow.
Luckily, in a healthy ecosystem, this cycle does not continue. As the chaos reaches its height, it begins to attract outside attention. What was once a glorious party enviable to even the most pompous emperor quickly turns into something more akin to shooting fish in a barrel. From among the skies and shadows, finely-tuned assassins leap to their tasks. The insect predators in our backyards are ancient killers, having honed their skills for hundreds of millions of years. For every pest on your plants, there are probably at least dozens of predators that specialize in putting it down. The wasps, beetles, mantids, dragonflies, and other tiny stalkers in our landscapes strike fear into every sap sucker and leaf eater they set their eyes on, and for good reason. If allowed to flourish, they are able to control most pest outbreaks all on their own.
The first predator you’re likely to encounter in and around your garden is a wasp. This is because wasps are everywhere, in every niche, in every biome. Wasps have an incredibly long and varied lineage, and the vast majority of them are solitary, living alone and doing their hunting solo. Like bees, this makes the majority of wasps very docile, and they are much more likely to run than try to put up a fight. Most can’t even sting.
It is believed that wasps account for around 50 percent of all insect-on-insect predation. Social wasps like yellow jackets are the minority, however they still play a large role in consuming prey to bring back to their young. Maintaining healthy pest populations is the best way to attract these opportunistic feeders.
Although some beetles feed on fungus, decaying wood, pollen, or other mostly inert foodstuffs, other species prefer the hunting lifestyle. Tiger beetles, equipped with powerful legs and vice-like jaws, have the speed to catch almost anything on open ground. Aerial beetles like ladybugs patrol your garden in search of aphids and other small pests, consuming their prey in both their adult and young forms. Predator beetles have even been brought in by local conservationists to help combat the hemlock wooly adelgid, which has devastated stands of this important native evergreen. Maintain areas of dense, uncut grasses to give beetles the prime real estate they’re after.
Praying mantids are indiscriminate hunters, able to target most garden pests without a second thought. There are several mantids native to the states, however most of the ones seen by gardeners are invasive species that outcompete American mantids. Avoid purchasing and releasing mantids, as they are most likely invasive.
If there is a water source nearby, dragonflies will be found in the air or perched waiting for a passing meal. They are capable of impressive acrobatics, flying at 35 mph and boasting an attack success rate of over 90 percent. Keep local waterways flowing and clean to ensure their young forms can mature properly into adults.
In our attempt to keep vulnerable plants healthy, the first spring flush of pests is often dealt with quickly and harshly, many times with pesticides as the preferred method. While this has impressive early results, the confident sprayer will soon find their dreaded pests returned just in time to feed on their plants as they fully recover. As this cycle continues, pest pressures actually tend to increase over time. Why? Well, to put it simply, in the vast majority of cases pesticide sprays cause longer lasting damage to the populations of natural predators in an area than to the pests themselves. This is compounded by the fact that the ‘first spray’ usually comes around at the same time that insect predators are beginning their life cycles. By putting some faith in your native predators, allowing pest populations to stick around year after year, and avoiding pesticide use, you can help foster these important animals while reducing your pest damage at the same time.
Brett Hondow photo (left)
Bugs That Harm, Bugs That Help
Polished Lady Beetle (left). Cicada Killer Wasp (right).
Be On the Lookout for a New Backyard Predator This Year: Cicada Killers
Did you see the emergence of a rarely seen (but easily spotted) insect predator? 2020 was to be a banner year for their favorite food—cicadas.
A group of cicadas known as Brood 9, the members of which have synchronized their life cycles to each other and only emerge as adults every 17 years, matured in abundance in and around western North Carolina this spring and summer. Cicadas don’t have much in the way of defense beyond their staggered maturation cycle, so they tend to burst forth from the ground in large numbers in an attempt to overwhelm hungry predators nearby. Perhaps the most effective, and most easily misunderstood, of these predators is the cicada killer.
Cicada killers are large, solitary wasps, with a red to orange tinge to their bodies. The Chinook helicopters of the garden world, these noisy and powerful hunters are able to paralyze a cicada with a single sting and carry it back to their nest, usually in the ground among dense groundcovers. Unless you’re a cicada, there is no reason to be afraid of these gentle giants, as their only mission is to provide their young with a snack or two.