Root System

Root System
Biomes	Any Overworld biome
Consists of	Oak Log; Azalea Leaves; Flowering Azalea Leaves; Rooted Dirt; Hanging Roots;

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A root system is a feature that spawns below naturally generated azalea trees.

Generation

A root system is a mess of rooted dirt blocks in a clump.

Data values

ID

Java Edition:

Feature type	Identifier
[No displayed name]	`root_system`

Configured feature	Identifier
[No displayed name]	`rooted_azalea_tree`

Config

Java Edition:

If the initial position is not air, root system fails to place. Root system checks every position, starting from the initial position and moving upward by [Int] root_column_max_height blocks. If it goes above the WORLD_SURFACE heightmap, root system fails to place.

At each position in order:

If the amount of air and water blocks above the position is less than [Int] required_vertical_space_for_tree or the highest water block is higher than [Int] allowed_vertical_water_for_tree, the position is not valid;
[NBT Compound / JSON Object] allowed_tree_position block predicate;
If [Int] level_test_distance is not 0, in each cardinal direction with an offset [Int] level_test_distance by XZ 2 points are checked with offset [Int] max_level_deviation by Y above and below. If below point is air or above point is not air, the position is not valid. That means if [Int] max_level_deviation is set to 0, this check will always fail;
If below block is lava or not solid, the position is not valid;
If [String][NBT Compound / JSON Object] feature fails to place, the position is not valid.

After a position is found, roots are placed within a [Int] root_radius along XZ [Int] root_placement_attempts times. They can replace only [String][NBT List / JSON Array] root_replaceable blocks. After roots are placed, hanging roots are placed within a radius, defined by [Int] hanging_root_radius along XZ and [Int] hanging_roots_vertical_span along Y [Int] hanging_root_placement_attempts times. If a block is air, then block predicates has_sturdy_face above and would_survive are applied.

[NBT Compound / JSON Object] config
- [Int] required_vertical_space_for_tree Value between 1 and 64 (inclusive).
- [Int] level_test_distance Value between 0 and 16 (inclusive).
- [Int] max_level_deviation Value between 0 and 64 (inclusive).
- [Int] root_radius Value between 1 and 64 (inclusive).
- [Int] root_placement_attempts Value between 1 and 256 (inclusive).
- [Int] root_column_max_height Value between 1 and 4096 (inclusive).
- [Int] hanging_root_radius Value between 1 and 64 (inclusive).
- [Int] hanging_roots_vertical_span Value between 1 and 16 (inclusive).
- [Int] hanging_root_placement_attempts Value between 1 and 256 (inclusive).
- [Int] allowed_vertical_water_for_tree Value between 1 and 64 (inclusive).
- [String][NBT List / JSON Array] root_replaceable A block ID or a list of IDs, or tag with # specifying which blocks can be replaced by the root column.
- [NBT Compound / JSON Object] root_state_provider The block to use for the root column.
  - Block state provider see Template:Nbt inherit/block state provider/template
- [NBT Compound / JSON Object] hanging_root_state_provider The block to use hanging below the root column.
  - Block state provider see Template:Nbt inherit/block state provider/template
- [NBT Compound / JSON Object] allowed_tree_position The block predicate used to check if the tree position is valid.
  - [String] type: The type of the block predicate. See Block predicate § Types for options.
  - additional fields depending on [String] type. See Block predicate § Types.
- [String][NBT Compound / JSON Object] feature The placed feature to place on top of the root system. Can be an ID of a placed feature, or a placed feature object.

An example

{
  "type": "minecraft:root_system",
  "config": {
    "required_vertical_space_for_tree": 3,
    "level_test_distance": 0,
    "max_level_deviation": 0,
    "root_radius": 3,
    "root_placement_attempts": 20,
    "root_column_max_height": 100,
    "hanging_root_radius": 3,
    "hanging_roots_vertical_span": 2,
    "hanging_root_placement_attempts": 20,
    "allowed_vertical_water_for_tree": 2,
    "root_replaceable": "#minecraft:azalea_root_replaceable",
    "root_state_provider": {
      "type": "minecraft:simple_state_provider",
      "state": {
        "Name": "minecraft:rooted_dirt"
      }
    },
    "hanging_root_state_provider": {
      "type": "minecraft:simple_state_provider",
      "state": {
        "Name": "minecraft:hanging_roots",
        "Properties": {
          "waterlogged": "false"
        }
      }
    },
    "allowed_tree_position": {
      "type": "minecraft:true"
    },
    "feature": {
      "feature": "minecraft:azalea_tree",
      "placement": []
    }
  }
}

History

Java Edition

Java Edition
1.18	Experimental Snapshot 1	Added root systems.
1.18	Pre-release 7	Root systems no longer generate underwater.^[1]
26.2	snap1	The field [String][NBT List / JSON Array] root_replaceable now also accepts an ID or a list of IDs in addition to a tag.
	snap6	New field [Int] level_test_distance.
	snap6	New field [Int] max_level_deviation.

Bedrock Edition

Bedrock Edition
1.17.0			beta 1.17.0.50				Added root systems.

Issues

Issues relating to "Root System" are maintained on the bug tracker. Issues should be reported and viewed there.

References

↑ MC-218592

[1] MC-218592

[1]