Spiders
Are a
Natural
Garden Pesticide
Despite the fear and
loathing they instill in many people, spiders can play a key biocontrol role in
your garden and landscape.
These eight-legged
predators are voracious eaters, and rarely pass up a chance for suppertime.
They’re usually not picky about what’s on the menu, and spiders are abundant in
number.
All spiders are predators
in that they don’t consume plants, only other living animals. They largely dine
on insects, but other spiders and some invertebrates or vertebrates may also be
snared. Spiders lie in wait for prey or aggressively seek it out. They may
capture prey in webs or hide and pounce when necessary. They are perfectly
happy consuming the pests that regularly damage flowers, foliage and vegetables.
However, keep in mind that because spiders aren’t discriminating in their prey,
they will also consume the helpful insects in a garden, such as honeybees and
butterflies.
Spiders live everywhere in
the world except for Antarctica and in the oceans. There are more spiders than
all vertebrates combined on the planet. Typically spiders use venom to subdue
prey. Digestive enzymes are regurgitated to liquefy prey since spiders do not
consume solid food.
Spiders are often
needlessly feared, say experts. They generally keep to themselves and are
virtually harmless when left undisturbed. There are very few spiders that have
bites that will require medical attention. In fact, most common spider fangs
are not even strong enough to penetrate a person’s skin. Through lack of
awareness, people tend to exterminate spiders even though they help to control
insect populations of more bothersome creatures.
Bringing Spiders to the
Garden
To invite arachnids to the
garden, try the following ideas.
a Provide places for spiders to build and
attach webs
Tall
plants, bundles of hay and crates are good options.
a Use mulch in the garden, since it
provides protection
and humidity for spiders.
a After the season, leave areas of the
garden untilled
and leave dead plant stalks so they
provide habitats
for spiders. Many will overwinter as
adults and can
get a head start on pest control in early
spring.
a Grow flowers that will attract prey.
Not
Really a Spider at All
You’ve probably
crossed paths with a Harvestman at one point in your life. Commonly referred to
as “daddy longlegs,” these arachnids really aren’t spiders. All arachnids share
the same traits of four pairs of legs, chelicerae (fang-like mouthparts) and
appendages near the mouth called “pedipalps.” But spiders are distinct because
they possess venom and silk, and have two distinct body segments. Daddy
longlegs do not produce silk and have no need for venom because they are
scavengers. These arachnids also have one oval body segment. Therefore, daddy
longlegs aren’t real spiders, despite being mistaken for them.