We have always told extension clients and students that the best tool for identifying an unknown weed is a good book, other than finding somebody who already knows what the weed is. We never thought much of the early weed ID apps that were developed for mobile devices. In AGRON 217 (Weed Identification), we even did an activity to demonstrate how hard they were to navigate. We would ask groups of students to identify an unknown weed; one group was provided a traditional ID book and another an app designed for identifying weeds. The group with the book would always identify the weed more accurately and quickly than the group with the ID app.
Times appear to have changed, and technology now can help anyone identify weeds (and other organisms). We recently took iNaturalist out for a test drive and are highly impressed with the speed at which it identifies plants. The free app is available for Apple and Android devices and requires only a quick registration to start identifying plants. A user simply takes a picture of the unknown plant, enters it into the system, and within a few seconds iNaturalist lists potential candidates. In some cases it will say it is not confident enough to make a recommendation, but may suggest a family or genus the plant could belong to. In nearly all cases that we’ve tried, the correct plant was at the top of the suggestions.
As good as this tool is, we’re not completely obsolete quite yet. The program does seem to struggle with broadleaf identification prior to the development of true leaves and identification of vegetative grasses.
iNaturalist originally was designed as a crowd-sourced identification system. People can post a photo of a species they didn’t know, and users of the program would help identify the image. As a side-project, developers initiated a machine learning program for identifying organisms. It is this machine learning tool that provides instant feedback. iNaturalist is a joint initiative of the California Academy of Sciences and the Natural Geographic Society.
We highly recommend the program for anyone interested in improving their weed identification skills, or anyone who simply has a curiosity about the living organisms they encounter. If you and the app are unsure of a plant's identity, don't hesitate to reach out to us or your local field agronomist for assistance with identification.
Steps in using iNaturalist
1) Open app and take picture of target or upload a photo you already have of the plant. Press the ‘Next’ button.
2) After entering the pic, this page appears. Clicking “What did you see” allows the app to provide suggestions on identification.
3) The response provided varies with the app’s confidence level. The app may state it isn’t confident in identifying the plant, but provides some suggestions. In this case it stated it thought the plant was in the Stellaria genus, which is correct since the photo was of common chickweed (Stellaria media).
4) By clicking on the 'i' next to the suggestion you can get information regarding the species