During this lab you will become familiar with how to use a dichotomous key as well as the nomenclature you need to know to understand it. In addition, we will dive into smartphone apps and how these help us in identifying plants...but their results are often flawed and should be viewed as helpful but not authoritative! As well as dichotomous keys we will also be introduced to multi-access keys that have become possible with the advent of computers. The point of this lab is not to miraculously be able to identify all plants, but to better know and practice the process of plant identification. We will be continuing to focus on our 8 major families: Mint - Lamiaceae; Mustard - Brassicaceae; Parsley - Apiaceae; Pea - Fabaceae; Lily - Liliaceae; Grass - Poaceae; Rose - Rosaceae; Aster - Asteraceae.
“Keying out” is a daunting but essential skill for anyone interested in Botany. To do this you need to know how Botanical (Dichotomous) Keys work, how to find your way around them, and their use and application – and their limitations. Additionally, multi-access keys are a new innovation along with picture-based smartphone apps as well as the versatile Google reverse image search or the new Google Lens.
There is a whole lot of plant jargon connected to plant physiology that we will not get into as part of this lab. Some of this jargon you will learn throughout the course while many terms will be left for your to research on your own as you go about using plant ID guides. There are three parts of this exercise...
Part I: Using Phone Apps
Nowadays we have an entire internet full of plant images and sophisticated algorithms to search your picture against this boggling world wide database. Though it should also be mentioned that these apps are not where they need to be yet and any answer they give you should be tested against some other source. Throughout this course you will be building up your plant knowledge so that by the end of the semester you will feel much more capable of truth-checking these apps yourself! Please read this article to familiarize yourself with the accuracy of different plant identification apps. The more common the plant, the more likely the ID will be correct!
There are a number of apps that work on smartphones for you to choose from. A couple of my favorites are Picture This and PlantNet. Lots of folks also like iNaturalist but I don't personally. PlantStory and LeafSnap are also fairly good options. I am actually starting to also use Google Lens which hooks directly into Google's massive database of images. It is basically an instant Google reverse image search for your smartphone.
All you are doing for this part of the lab is experimenting with at least 1 app-based tool for identifying plants. Your process is:
Find a plant, use an app (or a few different apps) to identify this plant
Once you have an identification look up this plant and use its description and compare to the plant in front of you
Make a determination of whether or not you agree with the ID you got from the app. If you don't that's fine...just make sure you have a good rationale that you can use to explain whether you accept the ID or not. As with the previous lab make sure you are able to intelligently describe your process using your plant knowledge.
Repeat this process for at least 6 plants so that you get more used to using apps to ID some basic plants (and truth-check the answers). At the end of the day you don't need 6 correct IDs, only 6 attempts for which you can adequately describe your decision process.
PictureThis*** - My personal favorite to date
Part II: Test Driving a Multi-Access key and comparing it to the dichotomous key approach
For decades dichotomous keys have been used for plant ID in the field. Of course times are changing now we all carry computers in our pockets! Still, using dichotomous keys is a useful skill to have. I will lead you through the process of using a dichotomous key to "key out" a couple specimens. Then, you will practice with dichotomous keys to make sure that you are able to use them yourself.
Now that we have computers we have multi-access keys. Some recent studies have found that these multi-access keys are faster and more intuitive than dichotomous keys. Instead of looking at one trait at a time, multi-access key users are able to list all the traits they see in their specimen and then ask the key to search through all candidate plants in its database to ID your specimen. It is a new powerful approach that may now be as portable as a field guide thanks to smartphones. For this lab you just simply need to test drive one of these apps and form an opinion on the experience. Feel free to use one of the plants you have already positively IDed. Here are some options for online multiaccesss keys to use:
My Recommendation: GO BOTANY by Native Plant Trust --- With this online multi-access key you are asked to first narrow down which group of plants you are looking at by answering a few simple questions (with pictures as support). Once you have answered these it takes you to a screen with a bunch of candidates. There are additional questions to answer in the left margin (you don't need to answer all of them) - again you are walked through these options with pictures and drawings. Once finished you are presented with the remaining candidates. This is made for New England but many of these species are also here in Indiana.
Other keys are as follows:
Be able to use apps on your phone for plant ID. Use your botanical knowledge in real time to either accept or reject these app-generated IDs. Be able to describe your process inteligently and persuasively.
Be able to use a dichotomous key to "key out" plant species. Know the associated jargon needed to use a dichotomous key.
Be able to use a multi-access key to "key out" plant species. Know the associated jargon needed to use a multi-access key.
Be able to articulate the differences between dichotomous keys and multi-access keys
Below are some other videos and links you may find useful with thinking about plant ID or when sorting through the nomenclature and terms used in keys. These are not required viewing/reading but may prove useful.
Leaf Shape - ovate; lance; elliptical; egg; linear; obovate; compound, palmate