[telegraph.hill]

Also on the topic of the commercial growing of crops, another worry is pesticides.

These end up polluting lakes, rivers and streams - not to mention the food itself! The water pollution inevitably impacts upon aquatic systems.

The use of pesticides also decreases the biodiversity of the soil. This damages the soil quality and actually reduces yields.

The two main chemical pesticides seem to be organophosphates and organochlorines, and although the organophosphates are somewhat safer, it appears that both types can cause health problems in farmers.

Obviously, we don't want crops to be eaten away by insects, but I believe that there are safer, more organic, more labour intensive methods of keeping insects and other pests at bay.

[Nate Martin]

Telegraph... you are right. about the organophosphates and organochlorines.

The characteristics of organochlorines are mostly hydro-phobic. So when present in the water column from agriculture return flows or stormwater runoff, the organochlorines tend to bind to the bottom sediment. This greatly affects the shellfish community which can also affect all the consumers of shellfish because organochlorines bioaccumulate....everyone has heard of DDT...although this is not used here in California anymore... (actually for 50 years) It is so resilient that if sediment in many rivers is sampled you will find DDT. The ones that are on the rise are pyrethroids.

Organophosphates such as Diazinon or Chlorpyrifos are also relatively dangerous. But luckily, OP pesticides are not as resilient as OC pesticides, and tend to break down faster in the environment. Diazinon does not bioaccumulate, but Chlorpyrifos does a little.

Nate

[bluemoon]

After reading your entries, I did a little research of my own on pesiticide alternatives. I campaign with Clean Water Action for pesiticde reduction in neighborhood parks. Let me know if any of these methods ring a bell or strike a chord:

Beet Armyworm and Cabbage Looper in Head Lettuce: Control with Selective and Reduced-Risk Insecticides - August 2003 - Yuma Co. Farm Notes (ACIS)
Foxglove Aphids in Lettuce: Control with Reduced-risk and Conventional Insecticides - June 2003 - Yuma Farm Notes (ACIS)
Reduced-Risk Insecticides For Leafy Vegetables and Melons (ACIS)
Review of New Insecticides Under Field Development For Desert Vegetable and Melon Production (ACIS)

Sam