Unincorporated county land is land that is outside of any incorporated city and is governed by the county. Unincorporated areas are provided with basic municipal services by the county government.
If they don't belongs to any city, what city name they would use in their address? Every address have to have a city name, not county name.
Let's find out
Step 1. select show address
https://transparentgov.net/json2tree/arcgis/featurelayer/click_feature225.html?backgroundlayerurl=https%3A%2F%2Fpublic.gis.lacounty.gov%2Fpublic%2Frest%2Fservices%2FLACounty_Cache%2FLACounty_StreetMap%2FMapServer%2F0&layer=Cities+and+Communities&dynamicLabelField=LCITY&symbolType=customized&_center_lat=33.970847746775725&_center_long=-118.2333375406578&_center_zoom=14&panto=0&tooltype=show_address
Step 2. Click anywhere in unincorporated area,
Address will show up
Step 3. try some other area, you will find that city name in unincorporated area is actually nearby city.
Finding:
Address does not necessary means it reside within city limit. It could be in unincorporated county land.
You can check your county land
Step 1. find your city boundary layer,
use model 225
https://transparentgov.net/json2tree/esri/server/folder.html?org=https%3A%2F%2Fpublic.gis.lacounty.gov%2Fpublic%2Frest%2Fservices&url=https%3A%2F%2Fpublic.gis.lacounty.gov%2Fpublic%2Frest%2Fservices&arcgis_online_token=&timeout=9000&select_folder=28&select_layer=0&select_folder_text=LACounty_StreetMap+%3Csup%3EMapServer%3C%2Fsup%3E&select_layer_text=0+%26%23x21E2%3B+Cities+and+Communities+%3Csup%3EFeature+Layer%3Csub%3E+esriGeometryPolygon%3C%2Fsub%3E%3C%2Fsup%3E
Step 2. add label and change color
Original city boundary color is too dark, you want to click customized color,
Original layer don't label as city name, you want to select city name as label