Weepwood is a block of Wood with olive-brown bark taken from a Weepwood-tree.
Usually, Weepwood-trees are also covered with a lot of Moss. When taking mossy Weepwood, you will obtain the moss, but not always get one block of Weepwood as well.
Mossy Leafis and Night Leafies (at ingame night-time) can spawn under and on Weepwood-trees, since update R24 also Feral Pigsies can be found in Swamplands. Mossy Leafies might as well spawn on Weepwood Leaves placed by players, while Feral Pigsies will spawn on Detritus in artificial biomes created by players.
Weepwood-trees cannot be grown from Saplings.
Weepwood-Flowers will not grow on Weepwood Leaves slowly like other tree-flowers do. But they can be multiplied by being placed and then picked up again which will occasionally yield an extra-block of Flowers additionally.
Weepwood as well as Weepwood Leaves of both kinds can be corrupted, like by Corrupt Bombs for example, or placing Corrupted Wood on/next to blocks of Weepwood touching them. Corrupted Wood and Corrupted Leaves are Fuel of much higher quality, they can only be picked up when using Lumite Mining Cells though, which will make it lose durability.
Unprocessed Weepwood can be used to craft a number of starting recipes in the Crafting Menu (opened with "Q" as the default key) or at a Crafting Table, like Wood Mining Cells, Processors or Moss Torches.