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 from a nearby block. Grass can spread to any immediately adjacent dirt blocks at the same height, including diagonally. It can also spread one level above and as many as three levels below. The grass jumps directly from one block to the other and is not affected by gaps or other blocks being "in the way".

In order for a grass block to spread, it must have a light level of 9 or brighter directly above it. Additionally, the dirt block receiving grass must have a light level of at least 4 above it and must not be covered by a block that reduces light by 2 levels or more. This includes any opaque block, as well as lava, water, ice, and some non-opaque blocks that light can't pass through, like slabs and stairs. Grass blocks can grow under all other transparent blocks, like glass, fences, torches, or pistons.

Grass blocks can be harvested by any tool with the Silk Touch enchantment. When mined in this way, a grass block will drop (the same as the block in the Creative inventory), and can be placed elsewhere, retaining the grass on top. This can be useful for creating grass patches in caves, the Nether, the End, or in the middle of a desert.

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 hills much faster than it spreads up them.

Grass can spread normally in both the Nether and the End, though it does not occur naturally in either.

Grass can be spread strategically by placing a trail of dirt blocks from a grass block to a patch of dirt. The process can take a while, but it can be sped up tremendously by creating a 3-block wide trail, and placing dirt blocks on the sides and on top, leaving a space above each block. This way, grass can grow to more of the adjacent dirt blocks, increasing the odds of transfer.

Grass can also be spread by the movement of grass blocks by Endermen. An Enderman holding a grass block can teleport elsewhere in the map and place the grass down on a plain dirt surface where the grass will grow as detailed above. This can lead to rare occurrences where grass may be found in caves or ravines.

Death


A Grass Block will die and change to dirt after a random time if covered by an opaque block. It can also die if it is covered by any block, and the light level above the grass block falls below 4. Transparent blocks can, contrary to popular belief, kill grass, but only if the surrounding area provides sufficient darkness.

For example, in direct sunlight, which is light level 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 excessive jumping or time left unplanted, which can then return to grass.

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

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.

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 (Steve?), were given as foldable decorations.
 * Grass was the second block to be added into Minecraft, after Cobblestone.
 * There is a very rare glitch where a specific area will be a different hue. You can fix this by destroying a block.
 * TNT's sounds for walking on, placing the block, and destroying it are the same as the grass block.
 * If you reach 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 colour (this is more easily noticed in swampland biomes).
 * Based on the spread pattern and apparent lack of a need for fixed nitrogen compounds (like NH3 aka ammonia, Minecraft grass resembles a cyanobacteria more than a plant.