Liz’s Dichotomous Key

I struggled a lot with this assignment, which is why I procrastinated it. I really enjoy the July flora in Alaska. The delphiniums, fireweed and monskhood are in bloom which are my favorite plants to admire. My Dichotomous key is based on those plants.

A. Flowers that alternate along the stem

A1. Flowers that do not alternate along the stem

              B. Flowers that have leaves

              B1. Flowers that do not have leaves

                             C. Flowers that are purple

                             C1. Flowers that are pink

                             C2. Flowers that are not pink or purple

                                           D. Flowers that have five petals

                                           D1. Flowers that have four petals

                                           D2. Flowers that have more than five petals

                                           D3. Flowers that have less than four petals


  1. Amanda Kemp

    Liz, I struggled too, but your dichotomous key is much more thorough and successful than mine! I thought it was helpful that you distinguished between flowers that do and do not alternate along the stem. That said, it will not be as useful when identifying plants that do not have flowers. My only recommendation is having a portion of the key used to identify spruce or other evergreens.


  2. Patricia Brown

    The challenge is to keep the key to just two choices per “tier.” That is what dichotomous means. I have introduced this to fourth graders by using shoes, one from each student thrown into a pile and we sit around in a circle. At each level there are only two choices. They might start with “shoes that have laces” and “shoes that don’t.” The second group would have boots, sandals, velcro straps, and anything else that isn’t secured with laces. Then within the group with laces, they might see one color more represented so they say, “black shoes and not black.” If they divided all by color there would be many more choices than two. So actually dichotomous keys simplify the path to identification, but without some basic experience with keys, I understand the frustration.

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