In this video we made a brief how to measure leaf area with a smartphone and a mobile application Petiole. It clear shows that specific leaf area measurement is not a problem and even to measure total leaf area is not an issue – less than in a minute with nothing special. Only Petiole and its Petiole kit (measuring stand and calibration pad) and three leaves of olive tree.

There are three main stages of leaf area measurement using a smartphone.

Installing a mobile application and launching Petiole mobile app

You need to download mobile application Petiole here (or for earlier version of OS Android, please, use this link). After successful installing, launch an app in your smartphone, allow to use camera. If you are using the mobile application Petiole for the first time – you need to register. Write your email and a password and remember this account credentials for your next visits. Now you can go to the calibration stage.

Camera calibration

After pressing the button “Calibrate Camera”, please, place the calibration pad in front of the smartphone’s camera. You will see the change of the color in a tiny square in the centre of the screen. Red square means that camera has not identified any calibration pad. Try to change a little bit its position. After the camera will be able to identify a calibration pad – the square will be green and you will see a number of calibration pad. We have a range of calibration pads for big or small leaves, depending on your research interests. If you see a green square – press a button “Setup” and you will be forwarded to a page with text “Calibration complete! Enjoy your measurements :)”. Now it is time to press “Continue”, take off the calibration pad and go to the next stage – to calculate leaf area.

Leaf area measurement

Now everything is ready for the main task, so, firstly, you need to place leaf or leaves (if you want to measure total leaf area) in front of the camera. The surface of leaves must be flat, not curvy, and this factor will improve the accuracy of your measurement. You can buy a Petiole special measuring stand for the purposes of fixing the height, reducing hand-shaking effect and making any leaf easy-to-measure. Details – in our website and via email.

After you have placed your leaves, point to the first leaf. You will see its area in square centimeters. On the right hand side of the measurement, you can see a button “Add”. Press it in order to sum the areas of all leaves. Then, one after one add all the areas to the area count. Finally, you will see the total leaf area and after finishing your measurements, just tap “New Plant” and your area count will be zero and Petiole is ready for the next measurements.

I hope, now the process of how to measure leaf area with a smartphone is clearer for you. So why not to try it? Good luck with your research!