QGIS Zürich 3.18 Win10 Using a point layer I can co-ord locate my trees. Graphically I want to display my points reflecting the Field trunk girth circumference and with a hard edged outer semi-transparent ring to reflect the Field Canopy circumference. Please point me in the right direction or suggest an approach. Eventually I shall use rule based expressions to graduate the Point colours by Field Species.
You could use multiple graduated symbols using your two attributes or you could add the layer twice to the project and use graduated size symbols for the tree canopy diameters. Then use colors to symbolize trunk girth.