Spiders: Friend or Foe?

Spiders are beneficial creatures and are the best bio-control agents known.  They should be tolerated as much as possible since they feed on large quantities of insects such as aphids, ants, thrips and termites. 

Most people would rather not have a house full of cobwebs. But spiders capture and consume many household pests including flies and once in a while, a centipede. Spiders are actually classified as arachnids and not insects; spiders have eight legs, insects have six.

There are over 3,000 species of spiders in the U.S., and only a small number of these are dangerous to people; very few are equipped with mouth parts that can actually pierce the human skin. 

For people who won’t tolerate spiders, here’s what to do.

·        The easiest and safest way to rid your house of spiders and their webs is to vacuum rather than spray.  The dust inside the vacuum bags will quickly suffocate any spiders you catch. If you’re willing to share the house with a few spiders, you can periodically vacuum up the webs that are eyesores and leave the spiders to continue their job of controlling the household pests.

·        If you can catch a spider in a jar, take and release him outside where he can continue working.  You might try caulking cracks and installing screens to prevents more spiders from coming inside.

Insect Signs and Symptoms

In order to successfully combat insects, and other pests, the correct identification must be made.  Often we can see the actual pest that is chewing on our favorite flowers.  But many times all that is seen is the damage - the sign that someone or something was there.  The following is a list of pest symptoms or signs with the corresponding probable cause.

·        Chewed leaves or blossoms  -  caterpillars, beetles, sawflies, snails, slugs.

·        Tunneling in the leaf – leafminers.  This insect actually feeds on leaf tissue as it meanders between the upper and lower layers of the leaf.

·        Stippled, bleached or yellowed leaves – leafhoppers, aphids, lace bugs, phyllids, mites

·        Distortion (twisting, cupping, swelling) of plant parts – thrips, aphids, eriophyid mites, bud mites, psyllids, gallmakers, true bugs.

·        Dieback of plant parts – borers, scales, tip miners, twig borers.

·        Presence of excrement – lace bugs, plant bugs, thrips, caterpillars.

·        Sooty mold – aphids, soft scales, whiteflies.

·        Froth – spittlebugs.

·        Cast skins – aphids.

·        Waxy, white material – aphids, mealybugs, adelgids, whiteflies.

·        Pitch tubes – pitch moths, clear winged moths, boring insects.

Unsuspected Causes of Plant Damage

A variety of plant diseases may lurk in the garden, but the odds are against it. Many professionals in the horticultural field estimate between 80 and 90% of all problems occurring in the garden are abiotic or non-infectious.  In other words, 10 to 20% of the problems are actually caused by some organism, some living creature – a rat, a bug, a fungus, a virus.  The rest of the problems are caused by too much or too little of an important environmental component that supports plant growth. Some examples are nutrient deficiencies OR excesses, a lack of water OR over watering, along with pesticide toxicities, air pollution, sunburn, frost and wind. So, when problems arise in the garden, investigate these noninfectious causes.