What’s Bugging You?

Debby Luquette
Adams County Master Gardener

(5/16) Seventeen years ago the third Friday of May was designated as Endangered Species Day to remind us of those species of plants and animals that are likely to disappear without some intervention from people. It might also be a good time to think about those ‘little things that run the world,’ as naturalist E.O. Wilson called insects. Many of them might become extinct before we even recognize their role in the world.

I know there are insects we consider pests, but only 1% of the known species eat, bite, sting, destroy property or otherwise disturb people and the other living beings. If we look closely at some of the things insects do for us, we find there are many times more than 1% which are beneficial. The rest seem merely benign from a human perspective, but maybe we just don’t understand their role in the world yet.

I am beginning to stop and pay attention to insects, and I find them fascinating. They are different in so many ways, even beyond all the body shapes, means of getting around, places they live and their ways of interacting with other creatures. So far, scientists have identified and named 1.5 million species of plants and animals, probably just a fraction of all the living and extinct life forms. Of that 1.5 million, one million of the named creatures are insects, and most of them are beetles.

Insects became the most successful group of animals on the planet after they first appeared around 480 million years ago; land plants appeared about this time, too. At that time plant reproduction was limited to moving their pollen equivalent from one plant to another in water, making them very short (mosses and ferns). Plants became more successful and diverse when pollen began moving on the wind. But the real advance, the development of plants with true flowers, coincided with the ability of insects to move the pollen from one flower to another.

But the insects that moved pollen weren’t the only insects that were successful. Scientists believe what truly made insects as a group so successful was that they became so diverse. When a new niche opened, an insect species soon filled it. They were able to take advantage of the opportunity because they could rapidly populate an area. Their small size, short life span and numerous offspring gave them advantages that allowed their populations to quickly adapt to opportunities presented by changes in their environment. Insects evolved in the face of a changing environment, and they still do.

Some species – like butterflies, beetles and flies – have life cycles which include a larval stage (caterpillars, grubs, maggots, etc.), allowing them to eat different foods at different points in their development. This makes more food choices available for their populations. We are familiar with lady bug larvae as aphid eaters while the parents enjoy nectar. Wasps are also nectar feeders as adults, while capturing and paralyzing insect prey as food for their young.

When we examine insects in the garden we recognize the many niches they fill. We like to classify insects that suck plant sap (like aphids), or eat plants outright, (like squash bugs), as pests, but when we plant a garden, insects are merely taking advantage of easy-to-acquire, abundant food which it would otherwise find in its more natural, non-garden environment. Yet, while we call them ‘pests,’ one of their roles in nature is to be food for other animals.

It’s Nature’s solution to garden pests. Have you noticed praying mantises prowling your garden toward the end of summer? I appreciate finding assassin bugs and robber flies that go after my pest insects. And, besides outright capture-and-eat predators, there are parasitoid insects that lay their eggs in the insect pest. After the eggs hatch, the larvae eat the victim’s insides before pupating to become another generation of parasitoids on pest patrol.

Part of the niche of some insects is being prey for other, non-insect predators. There are the pests, like the white cabbage butterfly caterpillars that love my kale and broccoli. But soft bodied insects, especially caterpillars, are the best food for growing bird chicks. Check out the birds scurrying around the garden in spring as they are gathering food for their broods. They help to protect your crop, so be careful with the insecticide.

There are the detritus feeders, eating decaying plant material; earwigs include plant detritus on their menu. They are making plant detritus more palatable for your worms and grubs. There are predators in the soil, too. Firefly larvae and other beetle larvae hunt and eat slugs and soft bodied insects in garden soil, too.

Niches aren’t just about what a creature eats. It also includes everything else the creature does as it interacts with its habitat. While insects are variable in how they eat, they are different in other aspects of their lives, as well. They have several means of locomotion; they fly, hop, walk, burrow, swim or just scoot over the ground. Niches include the habitat where the creature is found, along with temperature, humidity, day length and all the physical components of its habitat. There are insects adapted to all of them.

When you spend the time to investigate how the insects are interacting with your garden, you won’t find it difficult to see all the different ways these creatures are suited to their life in your garden. In fact, a suggested activity for the 17th Endangered Species Day is to find and observe 17 organisms. Identify them if you need to, but it’s alright to just enjoy watching them. If it’s an insect, so much the better.

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