{
  "feature": "clifftree:forest_fern",
  "placement": [
    {
      "type": "minecraft:count",
      "count": 20
    },
    {
      "type": "minecraft:in_square"
    },
    {
      "type": "heightmap",
      "heightmap": "WORLD_SURFACE_WG"
    },
    {
      "type": "minecraft:environment_scan",
      "direction_of_search": "up",
      "max_steps": 10,
      "target_condition": {
        "type": "minecraft:matching_blocks",
        "offset": [
          0,
          1,
          0
        ],
        "blocks": "#minecraft:leaves"
      }
    },
    {
      "type": "minecraft:biome"
    }
  ]
}
