Wildwood is a block of reddish Wood with dark bark taken from a Wildwood-tree.Wildwood Leaves hanging down to the ground instead of Vines. Some are so tall they have snow on top of them. However, these super-tall wildwoods only seem to be found in Reference Worlds 5 through 8 . You can locate them on the map by looking for light colored spots in jungle biomes, as seen in the picture below. The light colored spot is the snow on top of the tree. You can see how tall they are compared to the rest of the jungle in the picture below.
Taking a block of Wildwood for the first time will unlock the crafting-recipe for Bungalow Wall, which will then unlock even more Bungalow-related recipes if being crafted.
Wildwood-trees can rather easily be set on fire unintentionally, as the Jungle is a hot biome. Placing a torch under a block of Wildwood, Wildwood Leaves or any other flammable block/item can easily start a forest-fire that might even engulf a whole jungle and cannot be distinguished. Such a fire can merely be stopped from spreading further by creating wide forest aisles, also between tree-tops.
Wildwood Flowers of two kinds (glowing and not glowing in the dark) might grow on and amongst Wildwood Leaves and Dark Wildwood Leaves. Beehives will usually also hide amongst the leaves. Chizzards and Night Chizzards, also Leafies and Night Leafies can spawn under and on Wildwood-trees too, as they might as well spawn on Wildwood Leaves placed by players. On Detritus under Wildwood-trees Feral Pigsies can usually be found or can be spawned by players.
Wildwood-trees cannot be grown from Saplings currently (as of R25 in November 2015).
As Wildwood-Flowers will slowly grow on Wildwood Leaves and Dark Wildwood Leaves, these can be grown by placing Leaves in a large amount. Also Queen Bees can be planted on Wildwood as well as on Wildwood Leaves to grow into Beeswax. Just Dark Wildwood Leaves is no acceptable foundation for Queen Bees.
Wildwood as well as Wildwood Leaves of both kinds can also be corrupted, like by Corrupt Bombs for example, or placing Corrupted Wood on/next to blocks of Wildwood touching them. Corrupted Wood and Corrupted Leaves makes Fuel of much higher quality, has to be picked up by using Lumite Mining Cells though.
Unprocessed Wildwood can be used to craft a number of recipes like Wood Mining Cells, Processors or Moss Torches that will accept all kinds of Wood and can be accessed in the Crafting Menu (opened by typing "Q") or at a Crafting Table (which might still exist in older worlds created before September 2015).
Wildwood is also necessary to craft a wide range of Bungalow building-blocks and Bungalow furniture.