Grass Block



A Grass Block is a block that was introduced very early in the game. It uses 4 textures: a gray one for the top which is then tinted to the correct color according to what biome the block is in, one borrowed from the dirt block for the bottom, an edited dirt texture with grass on the top edge on all of the sides, and a gray texture matching the shape of the grass on the side of the block, which is tinted to the correct biome color. When covered by snow the side texture is white. On natural maps, grass appears on topmost blocks of dirt with no fluids or opaque solid blocks above them.

In mining, grass blocks behave just like dirt - they drop dirt resources and are best dug with a shovel; however, they make a different sound when harvested and take slightly longer to dig up. This can be used to tell when the player is about to break the surface when tunneling upwards.

Growth
Grass grows spontaneously only during map generation. Afterward, it can only spread to a nearby dirt block. Grass spreading without player intervention depends heavily on the time of day. In order for a dirt block to accept grass from a nearby grass block, the following requirements must be met: Light-reducing blocks include any opaque block, as well as lava, water, ice, and partially transparent blocks like stairs and single slabs. Grass blocks can grow under all other transparent blocks like glass, fences, torches, or pistons. Grass jumps directly from one block to a neighbor and is not affected by gaps or other blocks being "in the way". Grass blocks spread at random intervals and have an equal chance of spreading to any suitable dirt blocks that are in range. Because grass can spread as much as 3 levels downward, it tends to spread down slopes much faster than it spreads up them. Also due to this spreading 3 levels down regardless of obstructions, the player can later discover grass growing in dirt floored cellars or extremely shallow caves if the player previously lit them.
 * 1) The dirt block receiving grass must be within a 3×3×5 range of the source block where the source block is in the center of the second topmost layer of that range,
 * 2) The source block must have a light level of 9 or brighter directly above it,
 * 3) The dirt block must have a light level of at least 4 above it,
 * 4) Any block above the dirt block must not reduce light by 2 levels or more.

Harvesting grass blocks by hand or with most tools will drop a dirt block. However, grass blocks that retain the grass on top can be harvested by any tool with the Silk Touch enchantment. When mined with such a tool, a grass block will drop just like the same block in the Creative mode and can be placed in any valid location. This can be useful for creating grass patches in places where it doesn't naturally occur, such as underground, the middle of a desert, player made structures, or more exotic places like the Nether or the End. Once harvested with Silk Touch and the above requirements are met, grass blocks will spread normally in both the Nether and the End, though it does not occur naturally in either. Of course, dirt doesn't occur naturally in those places either, so it must also be brought in by the player in addition to the grass block.

Without using Silk Touch, the player can help grass spread by placing a trail of dirt blocks from a grass block to the patch of dirt where grass is desired. The process can take awhile, but it can be sped up by lighting the blocks so the grass also has a chance of spreading during the night. It can be sped up even further by placing dirt blocks on the sides and on top, leaving a space above each block. With this method grass can grow to more of the adjacent dirt blocks, increasing the odds of transfer.

Since Endermen can pick up some naturally occurring blocks, they can also unintentionally spread grass. An Enderman can pick up a grass block, teleport elsewhere in the map and place the grass block on or next to some dirt where it can spread if the above requirements are met. This can lead to rare occurrences where the player discovers grass growing inside caves or ravines that the player previously explored and lit.

Death


A Grass Block will die and change to dirt after a random time if covered by any block that reduces the light level above the grass block to 4 or below, including any opaque blocks, or the surrounding area is brought to sufficient darkness. Transparent blocks directly over grass can't kill the grass directly, if the surrounding area provides sufficient darkness, the grass will die.

For example, in direct sunlight with a light level of 15, grass will die with 4 or more water or ice blocks directly on top of it (assuming it isn't getting any extra light from the sides). In Moonlight, which is level 4, grass will die when covered by a single water or ice block.

Tilling a grass block with a hoe will convert it to a Farmland block, which can then revert to a dirt block from several causes, which can then return to grass.

Grass blocks also change to dirt when sheep "eat" them.

Uses

 * Animals will occasionally spawn on grass blocks that have light level 9 or brighter in the space directly above. This is quite rare and requires that there be few other animals nearby. Most animals are instead created along with the terrain. See the spawn page for details.
 * Passive mobs tend to wander towards grass blocks. They also wander towards light, but they ignore light over grass blocks and prefer them to any light levels below 10.
 * Bone Meal used on Grass Blocks will grow tall Grass and Flowers.
 * Sheep "feed" on grass blocks by turning them into dirt.
 * Sheep regrow wool when they "eat" a grass block.
 * Grass blocks can be used to make lawns, gardens or as a shade of green in pixel art that is on the ground.
 * A growing or dying grass block can be detected by a BUD. Therefore, growth and death conditions can be used to create a redstone light sensor.

Data values
A grass block has the ID name. A grass block also has a block state which is expected to replace the functionality of block data in a future version (though grass block doesn't currently use its block data).

Trivia

 * Grass blocks and dirt blocks changing between each other is a very common cause of chunk updates.
 * A grass block has become the favicon for Minecraft.net, and is the icon for the Minecraft launcher and the Pocket Edition app.
 * In MineCon's goodie-bags, grass, along with the Creeper, diamond, and the Player, were given as foldable decorations.
 * TNT and Sponge sounds for walking on, placing the block, and destroying it are the same as the grass block.
 * If at the edge of the rendered world (i.e. the edge of a chunk, where the adjacent chunk has not yet appeared), the edge line of grass blocks will adopt the "default" grass hue, until the adjacent chunk appears, at which point it will assume the correct color (this is more easily noticed in swampland biomes).