SAMPLING!!!

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Hi, everyone!

Thanks so much to everyone who has been writing to me - after I finish this post I'm going to see if I can figure out how to publish your comments! Dinner went very well, though I have a special surprise for everyone on Thursday night! Brenda's poison Ivy is much better, but HG sent a great idea for a plant cure - thanks HG!!
Today we did plot studies which is a great way to estimate all kinds of things about the ecosystem. Plot studies are a type of SAMPLING.

Basically, what we do is we go out to the woods and set up a plot - like we did on our field trips with the pink yarn. Today we went to a place that Rebecca (our fearless scientist leader) was very excited about going to. She said it's never been "dry" enough to go there before now, which means that they water is only about a foot deep above the mud!!

Here is Lisa balancing on a log to get to the "dry" plot! See Rebecca on the other side already.

















Instead of squares, we set up two intersecting pieces of tape that are each 10 meters long. We make it so they intersect at 90 degrees, like a plus sign + . We then imagine the circle that would have the plus sign as the center, and the tapes as diameters.







Once we set up the tape, two of us start checking all the leaves we can reach for caterpillars. We look for clues like "herbivory". Herbivory are holes in the leaves that mean something has been munching on the leaves.

These leaves have about 5% herbivory.













Today I was looking for caterpillars. When I found some, I put them in ziplock bags along with enough leaves for them to eat until they make a chrysalis. We label the bags with the type of caterpillar we think it is, the type of leaves, the date, and the plot number.















Two people estimate how many leaves are in the plot - yes, you have to count every leaf!
They also estimate what percent of the leaves have been eaten - this is the percent herbivory.














Sometimes you get lucky, like Rebecca, and caterpillars just show up on your clothes! This is a really cool caterpillar in the same family as the inch worm - the family's latin name is Geometrid - can you see what the family name has to do with the name "inchworm"?















On the way back to the bunk house we had the packs with the caterpillars in the back of the truck. All the sudden Rebecca said: "Oh, my gosh! Caterpillars all over the place!" and pulled over on the side of the road. Our carefully collected caterpillar bags were flying out of the truck all over the highway.
Becky, Lisa, and I ran around collecting all the bags before our data got smushed by giant trucks.
Yet another reason why you have to do a lot of trials!

Once we get back to the bunkhouse, we take out the bags and go through the one by one to make sure we have identified and counted the caterpillars correctly. Today we got almost all of them. Do you remember the one that was on Rebecca's jacket? We aren't sure what it is. I suspect it is the Southern Pine Looper (Caripeta aretaria), but there is no photo of it in the field guide. I couldn't find one on the internet either, so...... here is your




HOMEWORK CHALLENGE - choose one of the following:
1) Identify this cute guy whose survival adaptation is to mimic (make himself look like) a stick! Can you find a picture of the caterpillar Caripeta aretaria? How about a description? WE NEED YOUR HELP - REALLY!! Maybe you can find him on www.whatsthiscaterpillar.co.uk/america/ ?

2) Help me solve the following math problem. If 230 leaves in the plot had 0% Hervivory, and 210 leaves had 5% Herbivory, and 90 of the leaves had 10% herbivory, how could we come up with a percentage that would accurately represent the typical herbivory in the plot? (Remember: Herbivory is the holes in the leaf that the caterpillar ate.)