The Importance of Insects

I've just read a very informative post over at Native Backyard and I let her know I was going to post it on my blog.

I cringe every time I see commercials encouraging people to spread this poison over their lawns. Not only does it kill the bugs we don't want, i.e., fleas, ticks and grubs, but it is non-discramantory and kills bees and other very beneficial insects.

Plus I didn't know about tall fescue grass and the toll it takes on the soil. You know what they say - you learn something new every day!

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What group of lifeforms do we most need for our own survival? I'll give you a moment to think about it.


Ready? Insects. Avid students of gardening probably answered this without need of the white space pause. Here I paraphrase E. O. Wilson, from his book The Creation:


First there are the pollinators, without which flowering plants would cease to be in only a year or two. Other insect-pollinated plants would follow. Then the kicker: "The soil remains largely unturned, accelerating plant decline, because insects, not earthworms as generally supposed, are the principal turners and renewers of the soil."

In my personal quest to find the best combination of plants to create habitat, the lawn question led to more questions than answers, at first. I hope I will include enough information in this post to help you answer your own. My goal is to create lawn space that looks attractive but does not discourage other life forms that are necessary for the success of my "target" life forms (like songbirds). What I found was disturbing, with wide-spread impact.

In municipal and federal landscaping (think DOT), plants are searched out and chosen on the basis of low maintenance and high success rate. Over the years, this has contributed to many unintended consequences, such as the invasive presence in North Carolina (and many other states) of miscanthus. Some of these plantings have been so wildly successful that they have choked out other native species and the other life forms that depend on them. An example of this is tall fescue, which has led to drops in the population of (among other things) quail, which require huge numbers of insects for forage.

Tall fescue is an introduced grass. Around airports, as mentioned before, it is probably an excellent choice because it does reduce the population of potential airplane destroyers. It has a symbiotic relationship with a fungus (called an endophyte) that not only improves the viability of the fescue, but reduces the viability of insects. Without the insects, species like quail cannot survive.

Because of its success in choking out competition (and therefore requiring little if any weed control herbicides), tall fescues have been billed as an environmentally conscious choice for turf grass. So far as that standard goes, the marketing agents are correct. The fewer toxins we use in our landscapes, the better. That ought to be a no-brainer. However, if the goals is to sustain life, rather than just to inhibit it, tall fescues really, really fall short.

Agricultural industry has focused primarily on the "defeat the weed" strategy. So most research is aimed at solutions for weed-free turf or forage. A fine summary of this agricultural research comes from Cornell University. This type of research is not directed at finding which grass species support forage by other species, but rather on what is not required for species success--water, fertilizer and herbicides. Another approach was taken by Stevie Daniels. A Penn State Master Gardner, Daniels has worked to understand the best solutions for native turf grasses. She has selected the fine fescues as one of her lawn solutions, depending on your location. Others are discussed at the included link.

Fine fescues, based on what I can find, do not need endophytes to succeed. This would mean that they would not inhibit insect life the way that introduced tall fescues do. There may still be a threat of allelopathic(linked document has great chart) relationships to consider, but the native clumping red and sheep fescues should be safe choices for turf that won't disturb the balance of life. Mixed with violets like johnny jump-ups and other native, low-growing species, these less-aggressive fescues can help you achieve a lively lawn that allows the bugs (and bunnies...I'm all about the bunnies) to thrive. Which will make your birds happy.

The real point here, however, is that it is not just our songbirds who need bugs. We all do. We need them to pollinate our flowers and crops, we need them to till and aerate our soil, we need them to maintain the smaller life forms that feed us, either directly or indirectly. So in my own personal habitat, the quarter of an acre that I can control, it would be the height of foolishness to discourage my insects. I need to provide them all the sanctuary I can.

Posted by R K Young on Sunday, February 27, 2011