Friday, August 3, 2012
NSF GK-12 - Classroom Teachers and Resident Scientists Unite!
Sunday, March 9, 2008
Some stuff for the March 16 class
I'm planning on bringing and setting up a couple of things in for this coming Sunday's class.
KOH (potassium hydroxide)
KOH is used as an indicator stain to aid in the identification of a number of types of mushrooms, as well as as a rehydrating agent in microscopy. A 3-5% solution of KOH is commonly used as an indicator; examples of how it is used in mushroom ID can be be found here. Its a useful thing to have on hand.
I just bought some some bulk KOH for my own use – its sold in large quantities for use in making biodiesel, and my "small" purchase – 1 pound – ended up netting me a quantity that's entirely huge for my purposes. Since I've got so much excess, I'm going to bring some KOH and distilled water in next class and mix up a bunch of 5% KOH solution for anybody to take as needed. If you want some, bring in one or more small dropper bottles to fill up. You can buy these at Whole Foods, Elephant Pharmacy, and other such fine herbal-boutiquey kinds of places. Note that KOH is reactive, so metal or plastic containers are not the best choices for long-term storage.
While KOH is a caustic alkali, when diluted down to 5%, its pretty safe to handle. That said, if it comes in contact with your skin, you shouldn't let it stay in contact for more than a few minutes – wash it off, which is safe to do with water at this concentration. Also, it can bleach clothing it comes in contact with.
And, of course, if you use it to ID anything edible, don't actually eat the tissue you dropped the KOH on.
Microscopes
I'm going to bring in my compound scope again, and we already have a number of stereo scopes in the lab. I'll set these up to make observations, and I invite people to bring in mushrooms for observation. Stereo scopes are pretty straightforward, but setting up specimens and using (without damaging) a good compound scope is a little more involved, so I'll have to actually set up the slides and scope for observation.
For those of you who like to read up in advance about things you'll be seeing in class, there's some good stuff out there on the web about microscopes and mushroom microanatomy:
See you Sunday!
KOH (potassium hydroxide)
KOH is used as an indicator stain to aid in the identification of a number of types of mushrooms, as well as as a rehydrating agent in microscopy. A 3-5% solution of KOH is commonly used as an indicator; examples of how it is used in mushroom ID can be be found here. Its a useful thing to have on hand.
I just bought some some bulk KOH for my own use – its sold in large quantities for use in making biodiesel, and my "small" purchase – 1 pound – ended up netting me a quantity that's entirely huge for my purposes. Since I've got so much excess, I'm going to bring some KOH and distilled water in next class and mix up a bunch of 5% KOH solution for anybody to take as needed. If you want some, bring in one or more small dropper bottles to fill up. You can buy these at Whole Foods, Elephant Pharmacy, and other such fine herbal-boutiquey kinds of places. Note that KOH is reactive, so metal or plastic containers are not the best choices for long-term storage.
While KOH is a caustic alkali, when diluted down to 5%, its pretty safe to handle. That said, if it comes in contact with your skin, you shouldn't let it stay in contact for more than a few minutes – wash it off, which is safe to do with water at this concentration. Also, it can bleach clothing it comes in contact with.
And, of course, if you use it to ID anything edible, don't actually eat the tissue you dropped the KOH on.
Microscopes
I'm going to bring in my compound scope again, and we already have a number of stereo scopes in the lab. I'll set these up to make observations, and I invite people to bring in mushrooms for observation. Stereo scopes are pretty straightforward, but setting up specimens and using (without damaging) a good compound scope is a little more involved, so I'll have to actually set up the slides and scope for observation.
For those of you who like to read up in advance about things you'll be seeing in class, there's some good stuff out there on the web about microscopes and mushroom microanatomy:
See you Sunday!
Wednesday, February 20, 2008
Along the Steep Ravine trail
I found some nice mushrooms on a hike up the Steep Ravine trail on Mt. Tam this past weekend. I'll post a slide show on this blog - perhaps you all can help identify these, since some are new to me...Thanks!
No luck in Nevada City
I was in the Sierra foothills on Sunday, searching in the oak and madrone woods, but I found almost nothing. Maybe too dry or too cold. Thursday should be a good day after the rain. Can anyone identify this - I think it's Psathyrella multipedata.
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