{
    "feature": {
        "type": "random_selector",
        "config": {
            "default": {
                "feature": "minecraft:patch_grass",
                "placement": []
            },
            "features": [
                {
                    "chance": 0.33,
                    "feature": {
                        "feature": {
                            "type": "simple_block",
                            "config": {
                                "to_place": {
                                    "type": "minecraft:simple_state_provider",
                                    "state": {
                                        "Name": "minecraft:fern"
                                    }
                                }
                            }
                        },
                        "placement": []
                    }
                }
            ]
        }
    },
    "placement": [
        {
            "type": "count",
            "count": 3
        },
        {
            "type": "minecraft:in_square"
        },
        {
            "type": "minecraft:heightmap",
            "heightmap": "WORLD_SURFACE_WG"
        },
        {
            "type": "minecraft:biome"
        }
    ]
}