By Noelle Orloff, Associate Extension Specialist and Schutter Lab Diagnostician

Introduction

Screenshot of plant ID app interface.

Smartphone apps are available for almost anything these days, including plant identification. Plant ID apps are a helpful tool to have in your botanical toolbox. There are two broad categories of these apps.

Some plant ID apps function somewhat like a traditional key in that they require the user to enter information about the plant in question (picture, right) and based on the information the app lists plants that fit the criteria. Two apps in this category that are especially useful in Montana include Montana Grasses and Wildflowers of Montana/Montana Wildflowers. The identifications from these apps are only as accurate as the information entered; make sure to only choose a characteristic that fits your plant if you are certain you are correct.

Another group of plant ID apps uses artificial intelligence (AI) technology to identify plants based on photos a user takes with their phone (picture, bottom right). There are a number of these apps available.

Evaluating Plant ID Apps

I am often asked which of the AI apps I recommend. Thankfully, Dr. Erin Hill and her students at Michigan State University have evaluated these types of appsfor accuracy, testing them against plants with a known identity. Based on Dr. Hill’s criteria, in 2023 PictureThis was the most accurate app, and PlantStory and PlantNet were the second and third most accurate. There are other helpful apps available; test different apps on known plants in your area and see which one works best for you.

In many cases in Dr. Hill’s evaluation, apps correctly identified the genus of an unknown plant, while misidentifying the species. This has been my experience with these apps as well; they often help me get “close” to a plant’s identity but require further work to get to the correct species. The study also found that apps are better at identifying mature plants compared to seedlings, and grasses or grass-like plants may be more difficult for these apps to accurately identify compared with broadleaf plants. The group also tested the apps on Amaranthus (pigweed) species seedlings and noted that this was the most challenging task for the apps.

Tips for Using Plant ID Apps

Woman pointing smartphone at flowers on lab bench.

Whichever app you choose; it is important to use some critical thinking. Double check your identification using a trusted resource. Find accurate photos of many Montana plants online at the Montana Field Guide. The Latin binomial name will be the most helpful search term. Also check the USDA Plants Database and the Montana Field Guide to see if your identified plant is known to occur in Montana or not. To check your plant’s identification with a person, ask your local Extension office or your county weed district for assistance.  

Further Information

For more information about this month's weed post, contact Associate Extension Specialist Noelle Orloff. Past posts are available in the Monthly Weed Post Directory.

This weed post is also available as a printable PDF (246 KB).