Thank you all for your useful answers! I think there is a large potential for the use of mobile apps in forestry and environment. I will check those you recomended.
From my experience, this is very complicated problem. If you will try read my paper (I prepared the Artificial Intelligence for that) Article Design of intelligent decision support systems in agriculture
You can see some result. Basicaly, today don't exist technology, which give you current knowledge. If you want, I can prepare for you some deep learning models for plants, but today is the context of plants location, biotop etc at the AI missing and due it the plants recognition don't work perfectly.
If you are searchning somesing for MEASUREMENT - color, shape, size etc, so we developed the computer vision system HOR (https://www.uspin.cz/en/computer-vision) , in this case I can help you.