Plant Identification Tools and Resources

— Written By

With the arrival of spring, more of us are getting outside to enjoy the pleasant weather and new life budding and blooming all around us. Now is a great time to hone your naturalist skills, especially in plant identification.

Isn’t there an app for that?

The ubiquity of smartphones has resulted in the development of easy-to-use software applications and websites. Some of these are traditional taxonomic keys (more on those below), while others use image recognition and other artificial intelligence algorithms. The latter can be appealing to plant novices, as they tout rapid field identification with just a few clicks. However, the accuracy of many of these apps can be inconsistent. Valid identification depends on having quality photos to upload – lighting, position, contrast with surrounding vegetation, etc. Some plant parts are more variable than others, which is why taxonomists have historically relied on more complex and morphologically conservative reproductive organs (like sporangia, cones, flowers, and fruits) for accurate identification. 

Further, many features used to distinguish among genera and species can be subtle, cryptic, and esoteric. The very best AI-based apps with great photographs and location information can provide some level of accuracy, and can be adequate for a novice learner out on a hike or walking in a park. If it stimulates your interest in plants and the natural world, then apps can be a good place to start. However, consider this identification tentative and contingent on later validation. For a review of AI-based applications, see Jones (2020) AoB PLANTS 12(6) and Mark Weathington’s (Director, JC Raulston Arboretum) recent webinar. 

iNaturalist

iNaturalist is a web-based ‘social network’ of sorts for amateur and professional naturalists and biologists. Users can share images and request the identification of plants, animals, and fungi, relying on the shared crowd-sourced knowledge and experience of other members of the community. iNaturalist can also help track your own observations and has been used by scientists for certain kinds of biodiversity assessments. 

Online Classes from NC State Extension Gardener

In partnership with Longwood Gardens, NC State University offers a great series of online, asynchronous classes on plant identification. Students can learn about botanical terms and key features important for the identification of herbaceous, woody, edible, and ornamental plants. The online, interactive material is suited for all learning types. 

NC Extension Gardener Plant Toolbox

Our newly improved Plant Toolbox is primarily for learning about horticultural species, offering growing information, great photographs, and a ‘Find a Plant’ feature that can aid you in discovering the right plant for the right place in your garden or landscape. There is also an ‘Identify a Plant’ function that helps narrow down potential species based on different plant traits. 

NC State Herbarium Online Keys

Our herbarium is the second largest collection of preserved plant specimens in the state. Herbariums are essential tools for the scientific study of plant diversity and taxonomy, and employee academic and professional botanists who specialize in plant identification. Professor Alexander Krings and his team have developed a series of superb online keys and image galleries that are accessible and easy to use for amateur botanists. Included are dichotomous keys for trees in central North Carolina, pitcher plants, ferns, and even woody plants using winter twig features

Dichotomous keys present two sets of characteristics in a couplet. Users select one of the two choices that more accurately describes the specimen. Each choice will lead the user to a new couplet. This process is repeated until the final choice leads to a specific plant species. They can be somewhat challenging at first, but dichotomous keys are the best way to accurately and systematically identify organisms. Working through keys is also probably the best way to truly learn about the features of a plant, as you become intimately familiar with the variation of morphological features that will significantly improve your ‘eye’ for identification in the field. 

Recommended Books

There are several excellent field guides and books for North Carolina plants. Wildflowers of the Atlantic Southeast (Timber Press 2019) is a recently published book from a team at the North Carolina Botanical Garden that is easily the best wildflower guide for our region. This user-friendly field guide organizes wildflowers by flower color, and then by floral symmetry and leaf morphology. Descriptions, bloom period, distribution maps, and high-quality photos are provided for each entry. The beginning of the book includes an overview of the climate, geography, and plant communities of the southeast that provides a helpful ecological context for species distributions.

Book cover: Wildflowers of the Atlantic Southeast

Native Trees of the Southeast: An Identification Guide (Timber Press, 2007) is a comprehensive guide to trees of our region, providing summer and winter keys, thorough descriptions, photos, and brief ecological features of over two hundred species. 

Wildflowers and Plant Communities of the Southern Appalachian Mountains and Piedmont (UNC Press 2011) is a helpful companion to the other books. Common species are grouped by ecological communities (e.g., river bluff forests, roadsides, and fields, etc.), along with alphabetical descriptions of species that include good photographs and information on their habitat, taxonomy, ecology, wildlife benefits, and ethnobotanical uses. 

Sometimes botanical terminology can be overwhelming for the beginner. Even botany students and professionals often have copies of Plant Identification Terminology: An Illustrated Guide (Spring Lake Publishing 1994). This is two books in one: the first half lists common taxonomic terms in alphabetical order, the second half lists terms by morphological category (e.g., terms related to leaves, flowers, stems, etc), so if you come across an intimidating word in any of the above keys, start here for a description and illustration to learn what it means. 

Recommended Tools

Hand lenses are an affordable and essential tool for plant identification. They provide good magnification while being very compact. Hand lenses also have short focal lengths, so to use them properly, hold both the lens close to your eye and the sample close to the lens – moving the lens subtly to bring the object into focus. Penn State Extension and the NHBS both have helpful reviews of the best types of hand lenses for botanical use. 

Hand Lens

Hand Lens (AJC1 CC BY-SA 2.0)

Ask an Expert

If you need help with plant identification, reach out to your local N.C. Cooperative Extension horticulture agent. If your agent can’t ID a specimen, then they can send it to our group email list – someone will probably recognize it! However, just like with artificial intelligence, we need good photos too. Make sure the object is in focus, there is some indication of scale, and include images of the entire plant as well as the important parts – leaves, flowers, fruits, seeds, etc. Flowers and other reproductive parts are really important for species-level identification, so we might request that you wait and observe the plant until it flowers if we cannot ID based on vegetative parts alone. 

For especially challenging or rare plants, samples can be sent to weed specialists on campus (through your local extension agent!), or to the NC State Herbarium.

I will be offering more plant identification classes in the future in Chatham County. To stay tuned to those opportunities, subscribe to the Extension Gardener Portal and to the Chatham Gardener Newsletter.