Thursday, April 5, 2012

Attack of the Sap Suckers!

Ugly little beastie, isn't it?  That's one individual.  Have a look below to measure the infestation more accurately:

The plan was to save our own broccoli seed since it appeared to have over-wintered nicely, what with the mildish weather.  Instead, it appears as though what "wintered-over" is a nice healthy crop of these plant lice--or the more familiar term, aphids.  That's all that gucky-looking grey coating on the stems.  And, they suck the life out of the plants that host them.  

Some species of ants "farm" aphids, drinking the honeydew they produce.  That's all good and well for the ants.  For the farmer?  Not so much...
According to Wikipedia, there are about 4,400 species in 10 family groups worldwide.  
So, out here JOTOLR, we are now on the warpath with diatomaceous earth.  White clouds of this substance are enveloping the applicator (MM) over our emerging garden, promising relief from the chewing mites.  Apparently this white substance gets in the bodies and fouls up the insect's digestive system, leading to starvation.   I guess that's good.  Diatomaceous earth comes from (diatoms) tiny ancient seabed creatures.  It consists of the fossilized remains of diatoms, a type of hard-shelled algae.
Almost all of the earth is mined used open-pit mining techniques, where the earth is stripped away to reveal the deposits beneath it.  Hmmmmm.  More scarring of the earth...
 After being mined it has a multitude of uses:  as a filtration aid, mild abrasive, mechanical insecticide, absorbent for liquids, matting agent for coatings, reinforcing filler in plastics and rubber, anti-block in plastic films, porous support for chemical catalysts, cat litter, activator in blood clotting studies, and a stabilizing component of dynamite. As it is heat-resistant, it can also be used as a thermal insulator.
With all those uses, though, I wonder just how long we'll have that substance on the shelf...kind of like adding kelp to your garden....the kelp beds are vital support systems for a lot of sea creatures.  Does anyone think that kind of kelp harvesting can continue indefinitely without consequences?  Did anyone ask the sea otters or the sea horses what they thought of having their homes stolen?
I might just let the aphids run their natural course and skip the diatoms...


  1. Elora, aphids have piercing/sucking mouth parts so diatomaceous earth won't make it into the gut. Instead, the silica is scratching the surface of their cuticle and causing them to dessicate. You can achieve the same result by spraying them with soapy water. The soap washes away the oils from the cuticle and causes the aphids to dessicate. With either approach, you'll want to spray the plants with plain water to wash them off after the aphids are gone. Personally, I like the soapy water approach. Jim

  2. Many thanks, Jim! Great information!! Thanks too for the explanation about the DE not getting into the gut of the insects. I think the soapy water trick would be best, too. We're going to give it a try.