Tuesday, November 16, 2010

Black and Yellow Garden Spider

Black and Yellow Garden Spider

aka “Writing Spider” and “Corn Spider”

Kingdom: Animalia
Phylum: Arthropoda
Class: Arachnida
Order: Araneae
Family: Araneidae
Genus: Argiope
Species: aurantia
Habitat: Areas adjacent to sunny fields

Little Miss Muffet

Sat on a tuffet,

Eating her curds and whey;

Along came a spider,

Who sat down beside her

And frightened Miss Muffet away.1

The spider has a long history of a bad reputation that continues to this day. From nursery rhymes taught to toddlers, to FaceBook fan pages like “I don't care if the spider's "not hurting anyone", I want it dead.”2, to dark tales shrouded in misery as in the spider-woman of Dante Alighieri's Purgatorio (Canto XII). On the other hand, the spider has also been known since time immemorial as a teacher and helper of humankind. Spiders have creatively influenced many cultures, especially in the skills of weaving, spinning, basketweaving, knotwork, and net making. In the realm of the spirit the spider is often the weaver of destiny3 or the guardian of ultimate reality4.

Spiders are all of that, and more, but what spiders are mostly, according to Dr. Linda S. Rayor, Assistant Professor of Entomology, Cornell University5, are "beneficial inhabitants of every garden, ecosystem and home." They are considered to be the most important terrestrial predator because of their role in the biological control of pest insects and small arthropods.

Spiders are generalist predators, meaning they will eat almost anything they catch. They do not, however, eat plants. Being generalist predators they are a good control for any pest species plaguing a garden. However, since their generation cycle is a long one they cannot increase their population rapidly to meet an outbreak of pests. As well, being generalists, they do not differentiate between pest species and beneficial species. They will eat good and bad insects. On the other hand, many spiders overwinter as adults, and therefore are the first on the scene in Spring to help control pest species. Also being a generalist means they are a highly adaptive life form, able to survive in wide ranges of climate.

Spiders thrive in most habitats, and in Maine there are five common spiders, and an uncounted number of uncommon spiders. The most common spiders in Maine include the House Spider (Tegenaria domestica), Garden Spider (Argiope aurantia), Wolf Spider (Lycosidae), Crab Spider (Thomisidae) and Jumping Spider (Salticidae), there being many species of Wolf, Crab and Jumping Spiders in Maine.

The Black and Yellow Garden Spider weaves intricate web designs and wait within their webs, sitting in their trademark “X” stance, until something gets caught. Then they pounce. Although all spiders have venom, the bite of this particular spider rarely causes any problems in humans

These spiders spin a spirally vertical and orb web (spiral and circular shaped web) that radiates from the center. It is more complex as compared to other spider weavings. The web usually spreads over large areas up to 3 feet across. The adult male measures 8-9 mm in length, and the female grows to 19-28 mm or more at maturity. In addition to being large and spinning a large complex web, the Black and Yellow Garden Spider has specific features that make it every easy to identify. The distinctive black and yellow markings adorn the abdominal region, and the legs are black with red and yellow markings near the body.

The Black and Yellow Garden Spider prefers to weave its web in gardens, meadows, fields, shrubs, between tall grasses and tall plants. While females make a large orb web
which is characterized by a distinctive, white zig-zag pattern across it – hence the name “Writing Spider." The male weaves a smaller web on the outer edge of the large web. Breeding of this species occurs once a year.

The adult female lays
about 300-1,400 eggs in a brownish papery sac that of about 25 mm, and then dies. When autumn arrives the eggs hatch into young spiders, but overwinter inside the sac itself until spring when the young garden spiders disperse. They attain maturity that next autumn, and are ready to reproduce.

If you want to increase the number of spiders in your garden the first rule is not to use pesticides, herbicides or fungicides as spiders are vulnerable to nerve agents and poison. The second rule is to provide habitat, and that can be done in the following ways:
  • Use mulch. It provides protection and humidity.
  • Provide places for web attachment or homes: Crates, tall plants, bundles of hay.
  • Leave areas untilled or leave plant stalks for overwintering habitats.
  • Grow flowers that bring in prey.
A Relationships in Nature Chart which shows prey, predators, habitat plants and a food provider in the web of life around Black and Yellow Spiders is available at the Fairfax County (Virginia) Public Schools website.


BULLETIN #7150 of the Maine Department of Agriculture, Beneficial Insects and Spiders in your Maine Backyard

Galveston County (Texas) Master Gardeners, Beneficials in the Garden

1 I. Opie and P. Opie, The Oxford Dictionary of Nursery Rhymes (Oxford: Oxford University Press, 1951, 2nd edn., 1997), pp. 323-4.

2 As of 11/14/2010 there were 483,259 members of the FaceBook page: http://www.facebook.com/pages/I-dont-care-if-the-spiders-not-hurting-anyone-I-want-it-dead/220316776190?v=info

3 As associated with the Egyptian Goddess Neith, the Babylonian Goddess Ishtar, and the Greek Goddess Athena, to name a very few such associations. Cooper, JC (1992). Symbolic and Mythological Animals. London: Aquarian Press. pp. 214–15. ISBN 1-85538-118-4.

4 As in the Vedic philosophy, the spider is depicted as hiding the ultimate reality with the veils of illusion. Cicchetti, Jane (2003). Dreams, Symbols, and Homeopathy: Archetypal Dimensions of Healing. North Atlantic Books. p. 50. ISBN 1556434367. http://books.google.com/?id=0al1ZZtrnrsC&pg=PA50&dq=Spider+Grandmother+navajo+creation. Retrieved 11-14-2010.

5Rayor Lab, http://www.entomology.cornell.edu/cals/entomology/research/rayor/, Cornell University, College of Agriculture and Life Sciences, Entymology Department, retrieved 11-14-2010, and, Common Garden Spiders: All About Spiders http://www.coopext.colostate.edu/4dmg/Pests/spiders.htm, Colorado State University, retrieved 11-14-2010, and, Don't Kill Spiders: Spiders Are Good For Your Garden, http://planetgreen.discovery.com/travel-outdoors/avoid-killing-spiders.html , retrieved 11-14-2010

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