Naturally Bug-Free (2 page)

Aphids are often found in large colonies being tended by ants. The aphids benefit from predator protection, while the ants are allowed to consume excess plant sap that shoots through the aphids' system before it can be digested.

Aphids
include many species of tiny insects that suck the juices out of plants. I find it interesting that aphids rank #3 on
Mother Earth News
's survey of worst garden pests because, in my own garden, they only show up when I'm guilty of over-fertilization, and even then are quickly wiped out by predators.
Mother Earth News
gardeners treat aphids by pruning off infected parts, attracting beneficial insects, and applying insecticidal soap. I recommend first lowering the nitrogen content of your fertilization campaign, then ensuring that you have plenty of natural predators to go around.

The most common species of cabbageworm (top photo) is the larva of the cabbage white (
Pieris rapae
), sometimes confusingly called a "cabbage moth" even though it is really a butterfly. The southern cabbageworm (bottom photo) is the larva of the related checkered white (
Pontia protodice
), which is more common in the southern U.S. A few other caterpillars are also sometimes called cabbageworms.

Cabbageworms
come in multiple species, explained above. The most common cabbageworm is the caterpillar of the cabbage white, which I find easy to control by hand-picking in my own garden. Southern cabbageworms are much harder to control since they tend to live inside the florets of broccoli plants, where they're inaccessible until after harvest.

Mother Earth News
gardeners have reported luck with control strategies that include Bt, spinosad, row covers, and promoting caterpillar predators (such as paper wasps and yellow jackets). Timing seems to be relatively effective in my garden, since the cabbageworms are killed (or at least slowed down) by frosts in the fall and early spring. If we can get our broccoli and cabbage sets out into the garden early enough in the spring, we see little damage before harvest; similarly, a late-fall planting also misses the peak cabbageworm season.

Corn earworms are primarily a cosmetic problem in the home garden. Photo credit Ruth Hazzard, University of Massachusetts.

Corn earworms
(
Helicoverpa zea
) are caterpillars that tunnel into the ends of ears of corn, as well as into tomatoes and a few other crops. Despite being on the
Mother Earth News
top-pest list, I consider earworms to be only a cosmetic problem in our garden. Most of our ears of corn never get damaged, and it's easy to break off the affected portion on those that do. If you can't stand blemished fruit, though, you can prevent earworm damage by applying vegetable oil or Bt to the tips of ears when silks start to show, or by planting varieties with tight ear tips.

Spotted (left) and striped (right) cucumber beetles are problematic because they carry bacterial wilt disease. Photo credit: http://www2.ca.uky.edu/entomology/entfacts/ef311.asp.

Cucumber beetles
include two species: striped cucumber beetles (
Acalymma vittata
) and spotted cucumber beetles (
Diabrotica undecimpunctata howardi
). Both feed on melon and cucumber plants, transferring a bacterial disease known as wilt to the vegetables. Bacterial wilt symptoms begin with wilting of the leaves, followed by death of the plant. For a definitive diagnosis, cut the plant's stem and squeeze the cut ends; if the plant has succumbed to bacterial wilt, a sticky sap will ooze out and will form a long thread when you touch the two cut ends back together and then slowly pull them apart again.

Mother Earth News
gardeners recommend hand-picking cucumber beetles, treating with neem oil, cleaning up the garden to prevent overwintering locations, and utilizing poultry, row covers, companion planting, and yellow sticky traps. I simply succession plant my cucumbers, don't plant cantaloupes, and choose resistant varieties of both cucumbers and watermelons. (You can read about resistant varieties in chapter 6.)

Cutworms are caterpillars (top photo) that live in the soil and feed on young plants. When digging in the summer garden, you often find these species in the form of pupae (bottom photo), which are easy to remove and feed to your chickens.

Cutworms
are often invisible in the garden since they live in the soil, but you'll know you have these pesky caterpillars if your seedlings are beheaded in the night. Cutworms belong to any of several species of moths, but the most common in North American gardens is usually the variegated cutworm (
Peridroma saucia
).
Mother Earth News
gardeners recommend making little collars around the bases of seedlings to protect them from damage, cultivating soil before planting, or setting out larger seedings. Natural predators seem to keep cutworms under control in our garden during most years.

A grasshopper sheds its tough skin like a snake does, allowing the insect to grow larger.

Grasshoppers
included a number of species that eat leaves, but are rarely a problem in the vegetable garden. Most pest grasshoppers are members of the genus
Melanoplus
, including two-striped grasshoppers (
M. bivittatus
), differential grasshoppers (
M. differentialis
), migratory grasshoppers (
M. sanguinipes
), and redlegged grasshoppers (
M. femurrubrum
). Besides eating grass, grasshoppers enjoy the leaves of beans, leafy greens, and corn.
Mother Earth News
gardeners treat grasshopper infestations with hungry chickens and guinea fowl.

Japanese beetles often congregate in clusters as males compete to mate with a female.