Usually the Haunted Appletree mobs/Appletree Seedling are found in Avalon isle, just when entering the zone from Isle of glass but i cant find them anywhere. These mobs are great for necros around 18-22... Im not sure why their not here on this server... But I can see them in the SI Official prima guide.
https://ia800407.us.archive.org/13/items/Dark_Age_of_Camelot_Shrouded_Isles_Prima_Official_eGuide/Dark_Age_of_Camelot_Shrouded_Isles_Prima_Official_eGuide.pdf Prima guide page 29 on the map.
https://ia800407.us.archive.org/13/items/Dark_Age_of_Camelot_Shrouded_Isles_Prima_Official_eGuide/Dark_Age_of_Camelot_Shrouded_Isles_Prima_Official_eGuide.pdf Prima guide page 29 on the map.