When I bring in a big loads of salad greens, for example, I fill a huge bowl with cold water and aggressively "slosh" small batches of the greens in that water by hand. I do at least 3 changes of water with each batch - generally just keep a-sloshing and a-rinsing until I see absolutely no soil or particulates in the used water. Then I spin the batch dry and move on to the next small batch. If it is a really rainy or "sluggy" kind of day I wash in smaller batches to be very thorough. I have zero worries about parasites.

Oh cool! I've seen parasitic wasp pics on tomato horn worms (evil...evil horn worms), and always wanted to see them in my yard. They seem to look more like sacs hanging from the worm. Was this one stuck to that mass of yellowy eggs?. I saw ladybugs on my plum trees with lots of aphids. Go ahead aphids- have your fun now you little SOB's. Your day is quickly approaching ;)

burlap, I'm a teacher, too. I actually had the Tachinid flies go through their life-cycle in my Kindergarten class so the children could see what happens. I think it is a really good science lesson for them as it is a real-life lesson on what happens in the garden. The kids were fascinated by the whole process. Now that I am back teaching math in middle school, I've brought my 'bugs' into my math class. I have a table in the front of my room where my Elmo (projector) is and I put a few cups of larvae/eggs/assorted 'goodies' where the big kids can check things out before class begins or as they leave or if there's a minute here and there. They are all enthralled by the process as well and have now observed two Monarchs that have been parasitized by Oe and how the parasitoid effects them differently. I've had to discuss euthanizing the butterflies and what I do and why, which has brought us to some really good scientific discussions. It's also made many of the teenagers interested in butterfly gardening. There's a garden club on campus and the teacher who runs it has had more kids join in. :) He has Milkweed (I'd given him seeds several years ago) and now I am working with him on collecting eggs from any of the citrus plants as well as Milkweed plants. So, don't be afraid to share this more morbid aspect of Monarchs. I think it is a good thing to do, as it will broaden the children's thinking.

Let them alone...once they are parasitized they stop feeding...but they still appear to be alive. keep an eye on them, when the wasp's emerge from the cocoons it is is a thing of beauty.