Layer selection in ArcGIS Online not showing in sidecar map

[UConnCLEAR]

I have a map service that includes raster layers of land cover. The bottom layer is the full land cover and the other layers show one of the land cover classes. 

landcover/CTlandcover2015 (MapServer)  

In ArcGIS Online, I add the service and check on only one of the layers, for example, forest. 

When I select this map in the sidecar in the Storymap, the full land cover is visible and not just the forest. 

Note - I cannot add just the forest layer to ArcGIS Online via "Add Layer from Web" because they are rasters. 

Any ideas? Thank you. 

[OwenGeo · Accepted solution]

Unfortunately, group layers are not currently supported in the new ArcGIS StoryMaps. You'll need to republish the layers as individual services to work with them separately within the story builder.

[UConnCLEAR]

Ok, thank you.