Category: Dichotomous Keys

A: Are they short socks? – Type 1

A1: Are they long socks?

B: Are they multicolored?

C: Are they thin socks? – Type 2

C1: Are they thick socks? – Type 3

B1: Are they one color?

D: Are they thin socks? – Type 4

D1: Are they thick socks? – Type 5

 

A. Does the plant have flowers?

B: Is the flower purple? – Plant 3

B1: Is the flower white?- Plant 2

A1: Does the plant have needles?

C: Are they single needles? – Plant 1

C1: Are the bundled needles? – Plant 4

 

 

1. Plant has obvious flowers
   1. White flowers, four petals——–Plant 2
   2. Purple flowers, six petals———-Plant 3
2. Plant does not have obvious flowers
   1. Leaves form needles————Plant 1
   2. Leaves are fuzzy—————-Plant 4

Dichotomous Key Exercise

Leaves elongated to form needles………………………………………………………………..……….PLANT 1

Leaves not elongated to form needles:

Flowers lacking petals…………     …………………………………………….………………PLANT 4

Flowers with petals:

Flowers white in color………………….…………………………………………..PLANT 2

Flowers purple in color………………………………………………………..….PLANT 3

A1. Is the plant woody? Bin 1

A2 Is the plant herbaceous? Go to B

B1 Does it have a single flower? Bin 3

B2 Does it show inflorescence? Go to C

C1 Does it have visible petals? Bin 2

C2 Does it not have visible petals? Bin 4

Dichotomous Key

 

1. Cones & Needles – Bin 1
2. Leaf/Flower – Bin 2, Bin 3, Bin 4
   1. Lack of Petals – Bin 4
   2. Has Petals – Bin 2, Bin 3
      1. 4 Petals – Bin 2
      2. 6 Petals – Bin 3

 

At first this was a little confusing, I was thinking of the project in a really complicated way.  I then realized it could be thought of in a simple manner as a process of elimination. A little thought in organization and classification was important but being really technical was not (in this case).

Revised Dichotomous Key

indentation was not retained when I pushed publish, for some reason.

A   Needles ,   Bin 1

A1 Leaves, go to B

B Leaves with visible flowers, go to C

B1 Leaves with catkins/aments, Bin 4

C Flowers with white petals, Bin 2

C1 Flowers with blue/purple petals, Bin 3

Module 2

Dichotomous Key sample

Laura Emerson

For some reason, the post did not preserve the increasing indentation of each lettered section.

 

Bin 1:

A Tree with needles   …go to B

A1 Tree without needles… go to x (not demonstrated)

B Tree with cones … go to C

B1 Tree without cones… go to x

C   Tree with budding tips… go to D

C1 Tree without budding tips … (does that even exist? Or did I miss the   point of the photo?)

D Tree with something distinctive about its bark (cannot tell what).   … go to somewhere

D1 Tree lacking that something   (go to x)

Bin 2:

A Flower with four petals … go to B

A1 Flower with other … goXXX

B Flower pendulous … go to C

B1 Flower upright … go xxx

C Flower white… go to D

C1 Flower color other …

D Leaf oval … go somewhere

D1   Leaf other shape… go xxx

E Trichomes on the stem… go to xxx

E1 No Trichomes on the stem… go toxxx

Bin 3:

A.Flower blue/purple… go to B

A1.   Flower other color… go to xxx

B. Multiple stamens… go to C

B1.   Few stamens… go to xxx

C. Multiple pistils… go to D

C1.   Few pistils… go to xxx

B 4:

A Leaf elliptical (or is that lanceolate?) … go to B

A1 Leaf not that above… go elsewhere

B Leaf hairy… go to C

B1 Leaf not hairy … go elsewhere

C Multiple  stamens, fused to ovary … go to D

C1 Few stamens … go to xxx

 

 

 

Thank you for clarifying Steffi! I definitely made that assignment harder than it was meant to be. I redid it and this is what I came up with. Dichotomous Key