Tree ID

Today in science the students worked to identify a tree, using the parts I brought to school from my camping trip in early August.

Here’s what we had to help us:

  • seeds
  • seed pods
  • a small seedling

That was a lot of information to help the students figure out the species, but not quite enough.

One student tried using this dichotomous key from Wisconsin, but he got stuck when he needed to identify the pith in the stem. David couldn’t get beyond this step because we didn’t have a stem. There was missing information, so the next time I saw the tree, I plucked off a stem and brought it to school.

Now we had a wealth of information:

  • the seeds, pods, and seedling we had earlier
  • the leaf arrangement on the compound leaf
  • the leaf arrangement on the stem
  • inside the stem (the pith)

Students got busy searching on Sweet Search for terms like “dichotomous key”, “deciduous tree” (once they figured out how to spell it — their teacher had been no help), and “native Iowa trees” (the only clue I had given them).

Mason found a great dichotomous key, from Iowa State University, which I was sure would help him figure it out, but as he went through the questions, he got stuck on. Then I joined him, and I got stuck too. We knew it was broadleaf and compound leaf, and we thought the leaves were arranged oppositely. That’s where we became stuck because after that all the trees mentioned had samaras, which are small winged seeds. Our tree definitely had no samaras.

What would you say? These are the examples we had. It seemed we had a bit of both.

This photo of alternate leaf placement is so different than the leaves we have. Maybe that’s another reason we thought that was the wrong way. In the meantime, other students had gone ahead down the alternate path, which ended up being a wise move. The students went on to choose between thorns and no thorns (ours has none), smooth or toothed leaf margins (smooth), singly or doubly compound (doubly compound).

Finally, with a click on the last doubly compounded link the tree came up, and it was definitely our tree, the one we have in our classroom — The Kentucky Coffee Tree. (Gymnocladus dioicus)

Here are more pictures of the mysterious tree that has now been identified!

Flickr Set with Mystery Tree Images

You can find these Mystery Tree images and more on Flickr. You can use them for a mystery tree activity, for none of them have been tagged with the real name of the tree.

6 thoughts on “Tree ID

  1. This is authentic learning at its best. I bet the students loved the mystery and acting like detectives to figure out what tree it was. Will you ask them to reflect on their experience?

    I’m glad you explained in details what your students did. It made it feel as though I was there observing. Thanks!!

    • Thanks, Kris! Yes, they are writing their very first blog post about the experience. I wanted to write mine up to show them how. I’ll ask them to add links and photos too. This is a very bright group, who seem to be engaged with their blogs so far. We’ll finish tomorrow. Thanks for visiting.

      We’re adding pages to our blog this year to make a portfolio of our work. I’m exciting to see how that works.

      Thanks, as always, for visiting!

      P.S. Question for you…did your 8th graders write up their experience solving the crime scene? I would like to read those.

      • Yes, they did. I am going to write a post about their experiences. Went to Milwaukee this weekend so will do that either tonight or tomorrow night. Thanks for asking.

  2. Pingback: Krebs' Class Blogs » Blog Archive » Tree Identification in Science

  3. This is a very interesting venture into botany. One of my first year choices when in university had been botany. One of our key field projects was to build a personal 50 plant herbarium. Some I found were very tricky. I think I misidentified 7 of the 50. For 6, it was a matter of which plant within a species but, for 1, my tutor had asked what was I thinking. 🙂

    Teacher (retired), N.S.W., Australia

    • That’s a great story, Mr. Mannell. It’s funny how we remember stories like those. It makes us a better teacher, doesn’t it?

      Thanks for visiting my students’ blogs. They will be checking out the comments soon.

      Denise Krebs