Thursday, June 21, 2012

Plant Identification: Theory and Application

I am a novice foarger and plant identifier. My plant and tree "catalog" (plants that I can recognize and not need a book to identify... more on that below),while steadily growing, is still relatively small. In fact, it will never be complete no matter how long I study and practice. So obviously I'm no expert at this. However, I would like to share some theories on how we learn plants and some ideas on their practical  applications that may prove useful in how you learn plants.

Search Images

Samuel Thayer, in his excellent book The Foragers Harvest, discusses what he calls the "search image" as part of becoming a proficient forager. Thayer's ideas on how we learn to recognize plants are very intriguing and have helped shape the way I "train" myself to "identify" plants. Since I could not possibly word it better I'll simply quote him here:

When you become familiar with a plant your mind begins to develop a file of information and characteristics associated with it. This file, or set of associations, is what I call a search image. People do not recognize familiar things, whether a plant species or one of their parents, by specific distinguishing characteristics. Instead, we recognize them with respective search images, which contain far more details about their physical aspect than we could ever consciously remember. The search image contains more nuances of texture, shape, position, color, smell and other such things than could possibly be conveyed verbally.**

 Identification versus Recognition

Thayer also notes that there is a nuanced difference between "identifying" and "recognizing" a plant. I will again quote him:

 Identification comes first; it is a careful and deliberate process that one must go through as she becomes familiar with a particular plant. Recognition occurs when a functioning search image is built through repeated positive identifications. Every subsequent encounter with the plant will enrich and refine the search image until recognition is instantaneous and effortless. ***

Our Plant Catalog

We will not be discussing the process of identification - that's a rather dry subject that is covered ad nauseum elsewhere. Instead let's discuss how we can apply the above theories to become more proficient at recognizing plants.

All of the plants that we can recognize make up what I refer to as our "catalog" of plants. Each plant in that catalog has an associated search image composted of various identifying and associated characteristics (leaf shape, color, texture, ususal plant location, associated plants, etc.). That catalog is always growing. We not only add new plants but we also add details to each plant in the catalog. As we use the plant for food, cordage, medicine, or whatever we add more details. As the seasons progress we continuously update our search image and as we find the plants in more and more locations we add to our understanding of what the plant prefers and where we can look for it in the future.

Applying the Theories

So how can we efficiently add to our catalog? How can we best spend our limited time afield?

Firstly, once you have identified a plant, make a concerted effort to return to that plant throughout the seasons. Observe it in all of its stages. To do this I find an example of the plant from the previous year and observe it (for example) as it grows from a shoot to a small plant, as it flowers and as it develops fruit, as it fades in the fall, and finally even how it handles the winter months. Each time you visit the plant you add to that search image and expand that plant's entry in your catalog.

Secondly, continuously flip through your field guides. It is very useful to regularly just page through and look at the drawings and pictures. This not only adds to your search image but it also makes it possible to notice new plants. 

Here is an example: just yesterday I was out for a hike and sat down under a nice shady tree for a lunch break. When I knelt to repack my things I was met at eye level with a plant that instantly grabbed my attention. . My mind said "wait, you've seen pictures of that before"... it was familiar but had never seen in person before and I had no idea what it was or whether it was edible, poisonous, useful, or none of the above. A quick consultation with my field guide revealed that it was prickly gooseberry. I had never seen prickly gooseberry in person before and I had never made an effort to study the plant or seek it out. But, because I am constantly flipping through my field guides, I instantly recognized the plant as one I had seen in a book before. Now I know where to look later inn the season for some "delicious" berries! The same thing happened with garlic mustard, solomon's seal, and a few other plants just this spring.

On other occasions take the time to read a few entries in your field guides. Repetition is a valid learning tool. But what's more important is that you are categorizing aspects of that plant in your mind. When you read that a plant is found in swamps, for example, you'll know to keep an eye out for it the next time you're in a swamp, and you'll know that you don't necessarily have to be on the look out when you're in a sun baked clearing.

Thirdly, learn what plants tend to grow together or prefer the same conditions. This can be done both through your own field observations and through studying field guides. Knowing what plants grow together or prefer the same conditions means that you can use one easy to spot plant to find a smaller or more difficult to spot plant. Similarly, you'll know that if you recognize one plant you'll likely be able to find associated plants nearby. For example, morel hunters do not simply wander the woods looking for morels; that would be a tremendously inefficient waste of time. Instead they look for certain trees in certain areas that help them refine their tedious ground search. That way they can quickly eliminate or include relatively large areas in their search.

Regularly use the plants that you have learned. Don't just recognize them, also use them. This reinforces and adds to everything in your catalog. In the spring harvest some leeks and use them in your home cooking. On summer hikes stop for a quick nibble of berries along the trail. Make some dogbane cordage in the fall. In the winter add some wintergreen to your tea. The ways to do this are endless but the point is to get out and  get your eyes and your hands on them.

Finally, make an effort to visit unfamiliar places and identify or recognize plants there. Every new place that you see a plant adds to the catalog whether it's adding new information or reinforcing existing information.

So remember to take a field guide to work with you and flip through it on the commute or during lunch. Take a few minutes and peruse internet resources with pictures and drawings of familiar and unfamiliar plants. Get out in the fields and woods and look at what's around you... identify a plant, keep visiting it, harvest the useful parts, and really get to know it. Use the theories above to rediscover what our ancestors knew.

** Thayer, Samuel. The Foragers Harvest, pp. 28
*** Thayer. pp. 29

Of course you should always be certain of what you are eating and consult a quality field guide.Gather and consume wild edibles at your own risk. Etc., etc. etc....


  1. Man, edible plants is one of those topics that I always am wishing I knew more about. I need to remember to throw my guide in my pack on trips!

    1. The little bit of extra weight is surely worth it! Thanks for commenting.

  2. Fantastic info! Lately, some random and vague thoughts about this topic have been bouncing around in my head, and in this post you have brought it all together and laid it out clearly. Thanks!