FESTERING BLISTER BEETLES.  A gardener in southwest Ohio sent me some incredible images this week showing his tomato plants covered with margined blister beetles (Epicauta pestifera); the beetles outnumbered the leaves!  Blister beetles consume leaves and they're pretty common on annuals and herbaceous perennials in this part of the county, but I had never seen them causing such heavy damage to garden tomatoes.  Aside from feeding on plants, these beetles pack a serious defensive punch.  The beetle's blood contains cantharidin, a chemical that can cause severe blistering of the skin if the beetles are mishandled, hence the common name.  This chemical can also be toxic to people and animals if ingested.  Oddly, cantharidin is extracted from a European blister beetle to produce "Spanish Fly."

The larvae are specialized predators.  Some feed on grasshopper eggs while others feed in the nests of solitary bees where they consume bee eggs, larvae, and food stored in the nest.  Blister beetle adults may emerge en mass and produce rapid plant damage.  Fortunately, their visits are usually very short lived, lasting only a week or two.  They can be easily controlled if necessary by using a gloved hand to knock them into a bucket of soapy water (to be carefully disposed!), or by using an insecticide labeled for the host plant.

ALONG CAME A SPIDER.  I've gotten several calls over the past couple of weeks about spider webs appearing in home lawns ... 'tis the season.  This is the time of year when spider numbers start to climb and early morning summer dew may reveal their gossamer creations hanging between plants, draping over foliage, or appearing to float on top of the lawn.  Of course, the webs are how the spiders capture their meals and insects are the #1 item on the spider's menu.  They are our bio-allies!

Some spiders can be identified by their webs.  Orb weavers create circular webs, as their common name describes.  Web construction involves sticky and non-sticky silk.  Non-sticky silk is used for "radial threads" which radiate from a central point like spokes on a bicycle wheel.  The non-sticky silk is also used for "frame threads" which encircle the web like a bicycle wheel to hold the radial threads in place and to attach the web to supports such as plant stems or grass blades.  "Spiral threads" are composed of sticky silk arranged in a spiral pattern emanating from the center of the web; it's the sticky silk that captures the spider's prey.  Orb webs range in size from more than 1' to only a few inches in diameter, depending upon the spider species.

Funnel weavers produce large, flat, sheet-like webs spun across grass, under rocks or boards, or over the branches of shrubs such as yews and junipers.  The webs slope gently towards a narrow funnel or tube where the spider resides, awaiting its next victim.  Sheetweb weavers construct several types of webs depending upon the spider species.  Some species spin flat or slightly curved webs that overlay vegetation and rival the sizes of webs spun by funnel weavers.  However, there is no funnel in the web.  The spiders hide beneath one edge of the web, or in plant foliage along the edge of the web, to await their prey.

One of my favorite sheetweb spiders is the "bowl and doily weaver" (Frontinella communis).  This spider constructs a distinctly bowl-shaped web suspended from plant stems by a crisscrossing array of silk threads and anchored below by interweaving threads.  Flying insects drop into the web-bowl after bouncing in pin-ball fashion off the interlacing silk threads used to suspend the web.   Of course, when they drop into the web-bowl, they fall into the "arms" (and fangs!) of the awaiting spider!

There are several pesticides labeled for spider control; however, I urge that you apply restraint, appreciation, and understanding instead of pesticides.  Spiders are very important in reducing insect pest populations; they provide a great service free-of-charge by reducing the need for spraying to control more significant pests.