Using a drone for urban landscape situations is a bit ‘iffy’.
- Identify trees; tough to do without a lot of ground-truthing to verify what you are looking at. Looking down on tree canopies provides a different view than most are familiar with, so ID is tough. You might get down to genus level if your photo interpreter is experienced. It also depends on the common species in your area.
- Elevation changes; not really part of my experience. I’ll let others answer this.
- Turf disease/weeds; Same as #1. Depending on the disease you are looking for you may be able to spot some areas. Keep in mind that what you are looking for is areas of poor crop vigor. Subtle color differences are key here, so you may need special cameras or filters for best results. Again, not part of my experience.
- Plant beds/mulch; I will hazard a guess that this might be doable, if the beds have been maintained well in the past, so that mulch thinning is visible. Again, you will need to verify on the ground as you develop your program.
- This is probably better documented than most of the other issues. As in #3 above, you will find that special cameras and/or filters will help. Infrared photography is especially good at this. Again, the camera can show differences in reflectivity of IR light, which is then interpreted as drought, disease, or other factors.
You may not be able to get all this information at the same time. Landscape beds and turf condition will be impeded by tree canopy, so dormant season flights may be best. Tree canopy condition will be best interpreted during the growing season, but you may still need more than one flight. Spring (April through June depending on location) will show mostly vigorous growth if climate is close to normal, but summer (July through September or October) will better show the stress produced by heat and drought.
I am an arborist of 45 years, and have dabbled in using a Mavic Pro for several years. I gladly defer to others with more technical expertise on the drone issues.
Bear DE USA