This sounds more like a job for QGIS considering you are working trees. Partnered with QField, the app, you can create any number of “surveys” that will capture what you do on each pass (depending on how and what you set up), which you can then poll that data with the myriad of tools that QGIS has available. QField can also poll that data and display it to you in a limited form (QField is a mobile QGIS).
If you are fully pumped on the selfhost part, QFieldCloud can be selfhosted which each QField device/QGIS Desktop can then sync to and from each project you set up on that “cloud”. A syncing desktop user can see realtime what a QField user is adding to the map if they have a data connection available.
You can also go full data offline (if infield has spotty connection) if you create maptiles and share a basemap to each device via cable/network, or if you are selfhosting (or paid hosting) can also share those basemaps with each user. Borrowing a drone and mapping your property will get you extremely high quality basemap so you can zoom into even juvenile trees with a basic GPS but there are a lot of free imagery services about. There may be contour maps available for your area (our local government has 0.25m contours available), which you can stamp onto your basemap so people can instantly tell the lay of the land with a visual cue.
QField ships with 2 sample projects so you can get an idea (https://docs.qfield.org/get-started/sample-projects/). You can even import Excel sheets into QGIS if that interests you. Spreadsheet is good, but GIS adds a visual aspect that reinforces the overall project and helps laypeople work out exactly what’s where. It basically is a spreadsheet/database under the hood with any number of visuals on top. However you write your survey/s will dictate what is captured in the database. And this can include timestamped photos over the years if visual tree assessments are included.
Edit: https://qfield.org/success-stories/ for some examples. It can be as complicated or as simple as you need.
But thousands of people have it working just fine. Not calling you out but it does work very well. Did you follow a step by step guide? I know websearch makes it hard to learn new tech things these days.
Just keep in mind, set up a default folder and file (filename.kdbx) to share on one device, add Remote Device (QR code helps there), go to Sharing Tab and select Default Folder. If the Default Folder isn’t ticked on both devices in the Sharing Tab on each, nothing happens. When you work it out, that folder can be called anything and you can get advanced with how or when it shares or which direction the data goes (think photo backup from mobile to desktop).
New Android app to use is:
https://github.com/chenxiaolong/BasicSync
Use Obtainium- https://github.com/ImranR98/Obtainium - to install it and keep it updated. Obtainium can update itself the same way.
Convoluted, I know, but so is relying on a company to host for you in the cloud. They just hide all the complexity behind the interface. With Syncthing, once it’s set up between all your devices (and there is a way to quickly auto accept setup once further advanced/knowledgeable), it just chugs along in the background. Changes to keepass file appear almost instantly across each device once it’s opened.