Spiders, while gnarly, are good for gardens
Are you an arachnophile? Or, are you an arachnophobe?
If you are an arachnophile, you have an affection for spiders; if you are fearful of or dislike spiders, arachnophobe best describes your feelings towards these animals.
While spiders can be rather gnarly looking, evoking a shock and surprise when we find them in our gardens, they are an amazingly diverse group of creatures as well as an important garden ally.
Spiders belong to the taxonomic class Arachnida that includes ticks, mites, daddy-long-legs, and many others. There are over 45,000 known species of spiders world-wide, and about 3,000 species in the United States.Unlike some of the other arachnids, spiders do not eat plant matter in any of their life stages. All spiders are predators. They hunt other arthropods (insects and others with a hard exoskeleton) using a set of fangs to inject their prey with both venom to paralyze the prey and enzymes to liquefy the soft tissue within the exoskeleton.This combination of venom and enzymes allows the spider to suck the contents from their kill at their leisure, often wrapping the prey in a silk package for storage.Spiders do not bite people or other animals for a blood meal.Arachnophiles and arachnophobes can agree that spiders are very beneficial to our gardens. Spiders eat a phenomenal number of insect pests that would otherwise devour garden plants.Integrated pest management practices encourage the introduction of lady bugs and praying mantis to control unwanted insects. However, spiders can serve the same function, and you do not have to purchase them or nurture them.Let spiders roam freely in the garden; arachnophobes, just walk away from the spider or brush it aside and continue on your way!Even if you find a spider indoors, gently relocate it to the nearest houseplant, where it may take care of insect pests. Spiders serve as a food source for many other creatures including birds, chipmunks, frogs, toads and salamanders.
One fascinating aspect of spiders is their creative and effective approaches that have evolved to catch their prey.For example, the orb weaver spiders construct the familiar wagon-wheel shaped webs. These webs usually have sticky parts and non-sticky parts. The prey gets stuck in the sticky parts, but the spider knows where to step so as not to get caught in her own web.A group of orb weavers often found in Pennsylvania gardens are the “garden spiders.” These large spiders weave webs, often a foot or so across, that have what look like zippers woven into them. These are thought to be a warning to birds, so they will not fly through and destroy the web.Arachnophiles enjoy searching for spiders in their backyard landscapes. Gaze at your lawn on an early summer morning, and you will see a blanket of spider webs made visible by the clinging dew.As you look closely at the webs, you will see that many of them are funnel shaped. Hiding in the narrow part of the funnel will be a funnel web spider. This rather large, fast-moving spider lies in wait for an insect to stumble into its web.Crab spiders resemble little crabs that skitter sideways across a petal. Have you ever seen a jumping spider? Observe the spider for a second or two, and then it disappears. These spiders can jump vast distances in relation to their size.Wolf spiders, as their name suggests, do not spin webs to trap prey. Rather, they stalk their prey like a wolf. Their huge eyes allow them to hunt by sight.Unless you have an exoskeleton, arachnophobes need not worry that any of these spiders will seek them out as prey. Small spiders have tiny fangs too miniscule to pierce human skin. Some of the larger spiders may be able to puncture skin but would only do so in self-defense, perhaps if they had been trapped in a coat pocket.There are hundreds of species of spiders in Pennsylvania, but only two groups are of any concern to both arachnophiles and arachnophobes. The brown recluse and black widow spiders are rarely found in Western Pennsylvania, but are the only spiders whose bite may elicit a skin reaction.
The brown recluse spider, which is not native to Pennsylvania, has a distinct violin shape located on its back. The black widow spider, which is a Pennsylvania native, possesses a red hour-glass shape on the underside of its abdomen.Both spiders inhabit dark, undisturbed places such as woodpiles and outbuildings. Wearing gloves, long-sleeved shirts and long pants while moving woodpiles, undisturbed brush or cleaning out sheds and outbuildings should protect you from an unintentional spider bite.Penn State Extension has information about of spiders common to Pennsylvania (https://extension.psu.edu/commonly-encountered-pennsylvania-spiders; https://extension.psu.edu/general-information-about-spiders). Penn State Extension also provides details about the characteristics of specific spiders. Simply type into your search engine Penn State Extension spiders, and search through the results for the spiders of interest to you. The Extension also has a PDF of spider photographs and descriptions.Spiders are an integral part of the natural world, including our backyard gardens. Leaving them alone to do their job is an environmentally sustainable practice that helps to maintain nature's balance. Learning more about spiders may change you from an arachnophobe to an arachnophile!If you would like more information on spiders, call the Master Gardener Garden Hotline at 724-287-4761, Ext. 7, or email the Master Gardeners at butlermg@psu.edu.<i>Carol Chmielewski, MSc, is a Penn State Extension Butler County Master Gardener trainee.</i>
