Naturally Bug-Free (8 page)

Mole salamanders spend most of their life in the earth.

If you live outside North America, chances are you're unfamiliar with salamanders, and even many residents of the U.S. confuse these amphibians with lizards. Their scale-less, moist skin, though, is a dead giveaway that salamanders are relatives of frogs and toads, and that they depend on moisture in the environment to stay alive. If you maintain a heavy mulch in your garden, you may soon find mole salamanders moving in to eat your insects, worms, snails, and slugs.

Jackie Wilson emailed to tell me that, in her Pacific Northwest garden, "the slug problem was insane" until she started encouraging salamanders and toads with "little ponds in tall grasses, large damp compost piles with lots of coarse vegetable matter (like corn stalks and twigs), [and] rotting-log-lined berry beds.... The little ponds I refer to are simply the biggest plant pot saucers I can find, with a couple of flattish stones placed to make sure the critters can get in and out easily, next to an overturned container of some sort for snug cover. These are located in out-of-the-way wildish areas, which describes about 2/3 of the perimeter of my garden.... Love those amphibians, and they are much lower maintenance than ducks."

Farm animals

A young chicken enjoys a cicada.

Speaking of ducks, if you mention insect control to ten permaculturalists, at least nine will tell you to invest in these aquatic poultry. Others sing the praises of chickens, guineas, and muscovies, while geese are recommended as weeders of your garden. The idea is to utilize stacking—a central permaculture tenet—to gain multiple yields from the same garden space, all while letting your livestock do some of the farming work for you.

Poultry
do
have a lot of potential in the garden, but you'll find that it's more work to incorporate livestock into your garden than to simply encourage wildlife to do the same job for you. The trouble is that all poultry will eat (or mash down or scratch up) your garden plants if not managed carefully. That caveat aside, if you're going to raise poultry anyway, why not find a way to get them to eat some bad bugs in the garden too?

We've had the most first-hand experience with chickens, which we consider great friends for cleaning up weeds and soil insects on fallow ground. Chicken tractors are a handy way to keep your chickens in one small area so they don't toss around mulch, demolish tomatoes, and scratch up seedlings throughout the garden, and you can also let chickens run free in a summer-only garden during the cold season when nothing is growing. Harvey Ussery suggests that bantams may be a slightly better choice than standard-size chickens when free ranging in active gardens since bantams don't scratch as much, but any chicken is going to be a problem in an active vegetable garden. In an orchard or other perennial planting, though, chickens may be just what you need for insect control, as long as you ensure the birds have enough space so that they don't over-fertilize your plants.

Unlike chickens, which can provide eggs and meat, guineas are usually just raised for meat (or for eye candy). In the garden, guinea fowl are handy since they're reputed to control squash bugs, ticks, grasshoppers, and snails. I haven't heard from anyone who free ranges guineas in their vegetable gardens, but I suspect there would be similar caveats to those mentioned about ducks below.

So that brings us to the permaculture poster-child—ducks. I'll admit up front that I haven't personally raised ducks, but many premier permaculturalists have shared their extensive wisdom on the topic. First of all, there's the potential—ducks adore slugs, insects, and worms, while muscovies (a type of duck) are even known to hunt down flies. Meanwhile, the same ducks produce delicious and nutritious eggs and meat for their human keepers. However, as one of our blog readers reported, "[Ducks] are very destructive in the veg garden. We fence them out of the veg garden completely."

Carol Deppe, author of
The Resilient Gardener
, is perhaps the most-experienced duck-keeper in permaculture circles today. She loves ducks for their ability to control slugs in her Pacific Northwest garden, but warns "When it comes to greenery, ducks eat virtually everything people do, and more besides. So if you just turn a flock of ducks into a garden, you won't have a garden for long." Unlike chickens, ducks don't scratch, but their big feet do crush tender plants, their projectile poop makes vegetables much less appealing, and their voracious appetite means they eat up everything in sight.

How does Deppe work around these duck foibles? She fences ducks into areas just beyond the garden, where their droppings attract slugs that are promptly snapped up by the poultry. Deppe keeps Ancona ducks and reports that the fowl can be kept in by fences as low as two feet high, provided that the ducks have plenty of food and water and aren't separated from their friends.

Carol Deppe also lets ducks forage through her garden at intervals when she's standing by to keep an eye on them. She reports that ducks prefer insects and slugs over other food choices, so the birds will eat the pests first before chowing down on your tomatoes. However, you'll want to protect seedlings and low-growing greens before letting ducks into the garden for even these short field trips.

I hope that readers who've had extensive experience using poultry as insect control in the vegetable garden will drop me an email at [email protected] and share what you learned. I'd love to include your data in later editions of this book!

Chapter 4: Letting nature take its course

This beetle defoliated my asparagus plantings during our first couple of gardening years.

When trying to build a balanced garden ecosystem, there are times when you simply have to wait and hope. The hypothesis underlying this strategy is that nearly every pest insect has several predators just waiting to eat them up. But the predators don't have any reason to head to your yard until the pest insects reach a certain level—who wants to comb through an entire orchard in search of one colony of aphids? As a result, you sometimes have to hold onto your temper and let pest insect populations reach critical mass in hopes of attracting their predators. My experience with asparagus beetles taught me the importance of this often-overlooked pest-insect remedy.

I didn't know what I was seeing when the first asparagus beetle eggs and larvae showed up on my plants.

I used to think of asparagus as a do-nothing vegetable, so I wasn't terribly concerned when I first saw little grubs nibbling on my asparagus leaves. But within a couple of weeks, entire plants were defoliated! Research suggested my garden was suffering from an infestation of asparagus beetles, which lay their eggs in lines along asparagus fronds, then hatch into voracious caterpillar-like grubs. Asparagus beetles can go through several generations per year, so if you don't do anything and the beetles have no predators, large plantings of asparagus can be killed to the ground. That means you won't be eating many spears the next spring.
Traditional asparagus-beetle control consists of spraying Bt, which I'm leery of since this is a broad-spectrum insecticide (even if it is based on a bacterium). So, during the first year of our infestation, I hand-picked. (More on hand-picking in chapter 8.) This was a particularly difficult project since the asparagus fronds are tender and you really have to squish beetle eggs to kill them, plus it's hard to find the grubs and eggs amid all that greenery. To cut a long story short, the beetles won round one.
However, the next year I knew what I was looking for and I instituted early-and-often hand-picking. That fall, I cut down all of the dead fronds and raked up the mulch, adding the debris to the chicken coop for our flock to pick over. It also helped that I started to squish the asparagus beetles immediately upon their arrival that year, so my harvests broke the earliest cycles of asparagus beetles' egg-laying.

In this photo, a predatory stink bug has impaled an asparagus-beetle grub on its long snout.

But the tides didn't really turn until predatory stink bugs showed up. During the height of the asparagus-beetle infestation, I noticed the first of these beneficial insects dining, but one bug wasn't able to make much of a dent in the beetle population. However, by the next year, the tables had turned, and there were enough stink bugs and few enough beetles that the former were able to keep the latter in check. In recent years, my only nod toward asparagus-beetle control has been to squash one or two adult beetles and perhaps ten eggs in the spring, then to step back and let the predatory stink bugs do the rest of the work.

Which brings me back to the moral of the story. If I had sprayed Bt when the infestation began, the asparagus-beetle population wouldn't have built up to the point that predatory stink bugs would have come to call. And the chemical may also have harmed the beneficial insects, so there might not have been any predatory stink bugs around to hunt down the beetles that survived. This is the primary reason I eschew chemicals (even organic ones) in the garden. Sometimes, doing nothing will yield much better long-term effects, as long as you can hold onto your temper in the meantime.