diff --git a/.luacheckrc b/.luacheckrc
index 3664db6..b183edb 100644
--- a/.luacheckrc
+++ b/.luacheckrc
@@ -5,6 +5,7 @@ globals = {
     "minetest",
     "ebiometrees",
     "eaction"
+    "ebiome"
 }
 
 read_globals = {
diff --git a/mods/ebiome/api.lua b/mods/ebiome/api.lua
new file mode 100644
index 0000000..f934cb8
--- /dev/null
+++ b/mods/ebiome/api.lua
@@ -0,0 +1,6 @@
+function ebiome.register_biome(name, data)
+  if not data.type or data.type == "simple"
+  then
+    minetest.register_biome(name, data)
+  end
+end
diff --git a/mods/ebiome/config.lua b/mods/ebiome/config.lua
deleted file mode 100644
index 691b5ab..0000000
--- a/mods/ebiome/config.lua
+++ /dev/null
@@ -1,5 +0,0 @@
-ebiome = {
-  blocktypes = {
-    stone = "eterrain:rock"
-  }
-}
diff --git a/mods/ebiome/init.lua b/mods/ebiome/init.lua
index 3fc05ac..b01e32b 100644
--- a/mods/ebiome/init.lua
+++ b/mods/ebiome/init.lua
@@ -1,2 +1,3 @@
-dofile(minetest.get_modpath("ebiome") .. "/biomes/grasslands.lua")
+ebiome = {}
+dofile(minetest.get_modpath("ebiome") .. "/api.lua")
 
diff --git a/mods/ebiome/mod.conf b/mods/ebiome/mod.conf
index 1cbd7da..1a49e0b 100644
--- a/mods/ebiome/mod.conf
+++ b/mods/ebiome/mod.conf
@@ -1,3 +1,2 @@
-depends = ebiometrees
 description = biome mod
 name = ebiome
diff --git a/mods/ebiometrees/api.lua b/mods/ebiometrees/api.lua
new file mode 100644
index 0000000..529e25b
--- /dev/null
+++ b/mods/ebiometrees/api.lua
@@ -0,0 +1,16 @@
+ebiometrees.registered_trees = {}
+
+function ebiometrees.register_tree(name, data)
+  ebiometrees.registered_trees[name] = data
+  ebiometrees.register_subnodes(name)
+end
+
+function ebiometrees.register_subnodes(tree_name)
+  local modname = tree_name:match("([^:]*):")
+  local basename = tree_name:match(":([^:]+)")
+  local data = ebiometrees.registered_trees[tree_name]
+  ebiometrees.register_tree_sapling(modname, basename, data)
+  ebiometrees.register_tree_sprout(modname, basename, data)
+  ebiometrees.register_tree_leaves(modname, basename, data)
+  ebiometrees.register_tree_trunks(modname, basename, data)
+end
diff --git a/mods/ebiometrees/init.lua b/mods/ebiometrees/init.lua
index c3df1cb..4e09e8a 100644
--- a/mods/ebiometrees/init.lua
+++ b/mods/ebiometrees/init.lua
@@ -1,2 +1,12 @@
+ebiometrees = {}
+ebiometrees.directions = {
+  up     = vector.new( 0,  1,  0),
+  down   = vector.new( 0, -1,  0),
+  north  = vector.new( 0,  0,  1),
+  east   = vector.new( 1,  0,  0),
+  south  = vector.new( 0,  0, -1),
+  west   = vector.new(-1,  0,  0)
+}
 dofile(minetest.get_modpath("ebiometrees").."/sapling.lua")
 dofile(minetest.get_modpath("ebiometrees").."/tree.lua")
+dofile(minetest.get_modpath("ebiometrees").."/api.lua")
diff --git a/mods/ebiometrees/sapling.lua b/mods/ebiometrees/sapling.lua
index 34ca57b..07374d6 100644
--- a/mods/ebiometrees/sapling.lua
+++ b/mods/ebiometrees/sapling.lua
@@ -1,14 +1,3 @@
-ebiometrees = {}
-ebiometrees.directions = {
-  up     = vector.new( 0,  1,  0),
-  down   = vector.new( 0, -1,  0),
-  north  = vector.new( 0,  0,  1),
-  east   = vector.new( 1,  0,  0),
-  south  = vector.new( 0,  0, -1),
-  west   = vector.new(-1,  0,  0)
-}
-
-
 function ebiometrees.grow_closure(nextstage)
   local function growtree(pos)
     minetest.set_node(pos, {name=nextstage})
@@ -16,6 +5,7 @@ function ebiometrees.grow_closure(nextstage)
   return growtree
 end
 
+
 function ebiometrees.where_to_grow_trunk_closure(grow_preferences, leaves_name)
   local function where_to_grow_trunk(pos)
     for _, directions in ipairs(grow_preferences)
@@ -24,7 +14,14 @@ function ebiometrees.where_to_grow_trunk_closure(grow_preferences, leaves_name)
       local candidate_dir = directions[1]
       local candidate = vector.copy(pos):add(candidate_dir)
       local node = minetest.get_node_or_nil(candidate)
-      if node and node.name == leaves_name
+      corner1 = pos:add({x=-1, y=-1, z=-1}):add(candidate_dir:multiply(2))
+      corner2 = pos:add({x= 1, y= 1, z= 1}):add(candidate_dir:multiply(2))
+      local spacious, _ = minetest.find_nodes_in_area(
+        corner1, corner2, "group:treetrunk" 
+      )
+      minetest.chat_send_all(dump2(spacious))
+      minetest.chat_send_all(#spacious)
+      if node and node.name == leaves_name and #spacious == 0
       then
         return candidate
       end
@@ -33,20 +30,27 @@ function ebiometrees.where_to_grow_trunk_closure(grow_preferences, leaves_name)
   return where_to_grow_trunk
 end
 
-function ebiometrees.grow_trunk_closure(trunk_terminal_name, grow_preferences, leaves_name)
+
+function ebiometrees.grow_trunk_closure(trunk_terminal_name, grow_preferences, leaves_name, grow_limit)
   local function grow_trunk(pos)
-    local where = ebiometrees.where_to_grow_trunk_closure(
-      grow_preferences, leaves_name
-    )
+    local meta = minetest.get_meta(pos)
+    if meta:get_int("ebiometrees:distance")  > grow_limit 
+    then
+      return
+    end
+    local where = ebiometrees.where_to_grow_trunk_closure(grow_preferences, leaves_name)
     local there = where(pos)
     if there
     then
       minetest.set_node(there, {name=trunk_terminal_name})
+      local newmeta = minetest.get_meta(there)
+      newmeta:set_int("ebiometrees:distance", meta:get_int("ebiometrees:distance")+1)
     end
   end
   return grow_trunk
 end
 
+
 function ebiometrees.grow_leaves_closure(leaves_name)
   local function grow_leaves(pos)
     local free_node = minetest.find_node_near(pos, 1, "air")
@@ -60,8 +64,8 @@ function ebiometrees.grow_leaves_closure(leaves_name)
 end
 
 
-function ebiometrees.tree_grower(leaves_name, grow_preferences, terminal_name, nextstage, age_max)
-  local grow_trunk =  ebiometrees.grow_trunk_closure(terminal_name, grow_preferences, leaves_name)
+function ebiometrees.tree_grower(leaves_name, grow_preferences, terminal_name, nextstage, age_max, grow_limit)
+  local grow_trunk =  ebiometrees.grow_trunk_closure(terminal_name, grow_preferences, leaves_name, grow_limit)
   local grow_leaves = ebiometrees.grow_leaves_closure(leaves_name)
   local function grow_tree(pos)
     local meta = minetest.get_meta(pos)
@@ -80,8 +84,3 @@ function ebiometrees.tree_grower(leaves_name, grow_preferences, terminal_name, n
   return grow_tree
 end
 
-function ebiometrees.root_sapling(pos)
-  minetest.set_node(pos, {name="ebiome:oak_sprout"})
-  return false
-end
-
diff --git a/mods/ebiometrees/tests/ebiometrees_api_spec.lua b/mods/ebiometrees/tests/ebiometrees_api_spec.lua
new file mode 100644
index 0000000..d98268f
--- /dev/null
+++ b/mods/ebiometrees/tests/ebiometrees_api_spec.lua
@@ -0,0 +1,40 @@
+package.path = "../?.lua;" .. package.path
+
+_G.ebiometrees = {}
+require("api")
+require("tree")
+require("sapling")
+
+registries={}
+
+
+function _G.ebiometrees.register_tree_trunks(m, n, d)
+  registries.trunks = m..":"..n
+end
+function _G.ebiometrees.register_tree_sprout(m, n, d)
+  registries.sprout = m..":"..n
+end
+function _G.ebiometrees.register_tree_leaves(m, n, d)
+  registries.leaves = m..":"..n
+end
+function _G.ebiometrees.register_tree_sapling(m, n, d)
+  registries.sapling = m..":"..n
+end
+
+testtree = {
+  groups = { foo = 1}
+}
+
+describe("Trees", function()
+
+  it("can register tree", function()
+    assert.is_nil(ebiometrees.registered_trees["test:tree"])
+    ebiometrees.register_tree("test:tree", testtree)
+    assert.is_not_nil(ebiometrees.registered_trees["test:tree"])
+  end)
+  
+  it("attempts to register sapling", function()
+    assert.is_equal("test:tree", registries.sapling)
+  end)
+
+end)
diff --git a/mods/ebiometrees/textures/ebiometrees_indicator.png b/mods/ebiometrees/textures/ebiometrees_indicator.png
new file mode 100644
index 0000000..107283e
Binary files /dev/null and b/mods/ebiometrees/textures/ebiometrees_indicator.png differ
diff --git a/mods/ebiometrees/textures/ebiometrees_indicator2.png b/mods/ebiometrees/textures/ebiometrees_indicator2.png
new file mode 100644
index 0000000..637871e
Binary files /dev/null and b/mods/ebiometrees/textures/ebiometrees_indicator2.png differ
diff --git a/mods/ebiometrees/textures/ebiometrees_indicator3.png b/mods/ebiometrees/textures/ebiometrees_indicator3.png
new file mode 100644
index 0000000..6488584
Binary files /dev/null and b/mods/ebiometrees/textures/ebiometrees_indicator3.png differ
diff --git a/mods/ebiometrees/tree.lua b/mods/ebiometrees/tree.lua
index be0b012..4b3375f 100644
--- a/mods/ebiometrees/tree.lua
+++ b/mods/ebiometrees/tree.lua
@@ -1,52 +1,13 @@
+
 local function growth_timer(pos)
   minetest.get_node_timer(pos):start(3)
   local meta = minetest.get_meta(pos)
-  meta:set_int("ebiometrees:age", 0)
   meta:mark_as_private("ebiometrees:age")
+  meta:set_int("ebiometrees:age", 0)
 end
 
-
-local S = minetest.get_translator("ebiometrees")
-function ebiometrees.register_tree(modname, basename, data)
-  -- register saplings
-  local sapling_name = modname..":"..basename.."_sapling"
-  local sprout_name = modname..":"..basename.."_sprout"
-
-  local sapling_groups = table.copy(data.groups)
-  local sprout_groups = table.copy(data.groups)
-  sapling_groups.sapling = 1
-  sapling_groups.snappy = 2
-  sapling_groups.dig_immediate = 3
-  sprout_groups.sapling = 1
-  sprout_groups.snappy = 2
-  minetest.register_node(sapling_name, {
-    description = S(data.description.." sapling"),
-    drawtype = "plantlike",
-    tiles = { modname.."_"..basename.."_sapling.png"},
-    paramtype = "light",
-    on_timer = ebiometrees.grow_closure(
-      modname..":"..basename.."_sprout"
-    ),
-    sunlight_propagates = true,
-    walkable = false,
-    groups = sapling_groups,
-    on_construct = growth_timer
-  })
-  minetest.register_node(sprout_name, {
-    description = S(data.description.." sprout"),
-    drawtype = "plantlike",
-    visual_scale = 1.4,
-    tiles = { modname.."_"..basename.."_sprout.png" },
-    paramtype = "light",
-    sunlight_propagates = true,
-    walkable = false,
-    on_timer = ebiometrees.grow_closure(
-      modname..":"..basename.."_trunk_growing_terminal"
-    ),
-    groups = sprout_groups,
-    on_construct = growth_timer
-  })
-  -- register tree leaves
+function ebiometrees.register_tree_leaves(modname, basename, data)
+  local S = minetest.get_translator(modname)
   local leaves_groups = table.copy(data.groups)
   leaves_groups.leaves = 1
   leaves_groups.leafdecay = 3
@@ -61,6 +22,54 @@ function ebiometrees.register_tree(modname, basename, data)
     is_ground_content = false,
     groups = leaves_groups
   })
+end
+
+function ebiometrees.register_tree_sapling(modname, basename, data)
+  -- register saplings
+  local S = minetest.get_translator(modname)
+  local sapling_groups = table.copy(data.groups)
+  sapling_groups.sapling = 1
+  sapling_groups.snappy = 2
+  sapling_groups.dig_immediate = 3
+  minetest.register_node(modname..":"..basename.."_sapling", {
+    description = S(data.description.." sapling"),
+    drawtype = "plantlike",
+    tiles = { modname.."_"..basename.."_sapling.png"},
+    paramtype = "light",
+    on_timer = ebiometrees.grow_closure(
+      modname..":"..basename.."_sprout"
+    ),
+    sunlight_propagates = true,
+    walkable = false,
+    groups = sapling_groups,
+    on_construct = growth_timer
+  })
+end
+
+function ebiometrees.register_tree_sprout(modname, basename, data)
+  -- register tree leaves
+  local S = minetest.get_translator(modname)
+  local sprout_groups = table.copy(data.groups)
+  sprout_groups.sapling = 1
+  sprout_groups.snappy = 2
+  minetest.register_node(modname..":"..basename.."_sprout", {
+    description = S(data.description.." sprout"),
+    drawtype = "plantlike",
+    visual_scale = 1.4,
+    tiles = { modname.."_"..basename.."_sprout.png" },
+    paramtype = "light",
+    sunlight_propagates = true,
+    walkable = false,
+    on_timer = ebiometrees.grow_closure(
+      modname..":"..basename.."_trunk_growing_terminal"
+    ),
+    groups = sprout_groups,
+    on_construct = growth_timer
+  })
+end
+
+function ebiometrees.register_tree_trunks(modname, basename, data)
+  local S = minetest.get_translator(modname)
   -- registers corresponding trunk nodes
   local trunk_groups = table.copy(data.groups)
   trunk_groups.choppy = 2 -- TODO: customizations
@@ -154,7 +163,8 @@ function ebiometrees.register_tree(modname, basename, data)
             },
             modname..":"..basename.."_trunk_growing_terminal",
             modname..":"..basename.."_trunk_normal_"..trunk_subtype,
-            20
+            20,
+            10
           )
       end
       minetest.register_node(
diff --git a/mods/ebiome/biomes/grasslands.lua b/mods/electric_biomes/biomes/grasslands.lua
similarity index 68%
rename from mods/ebiome/biomes/grasslands.lua
rename to mods/electric_biomes/biomes/grasslands.lua
index b3b9f59..c28de5d 100644
--- a/mods/ebiome/biomes/grasslands.lua
+++ b/mods/electric_biomes/biomes/grasslands.lua
@@ -1,4 +1,4 @@
-local S = minetest.get_translator("ebiome")
+local S = minetest.get_translator("electric_biomes")
 minetest.register_biome({
     name = "grasslands",
     node_top = "mapgen_topsoil",
@@ -10,13 +10,13 @@ minetest.register_biome({
     heat_point = 50,
     humidity_point = 50,
 })
-ebiometrees.register_tree("ebiome", "oak",{
+ebiometrees.register_tree("electric_biomes:oak",{
   description = "Oak",
   groups = {flammable = 2}
 })
-minetest.register_node("ebiome:grass", {
+minetest.register_node("electric_biomes:grass", {
   description = S("Grass"),
-  tiles = {"ebiome_grass.png"},
+  tiles = {"electric_biomes_grass.png"},
   drawtype = "plantlike",
   visual_scale = 1.4,
   waving = 1,
@@ -29,8 +29,8 @@ minetest.register_node("ebiome:grass", {
     fuel = 1
   },
 })
-minetest.register_alias("grass", "ebiome:grass")
-minetest.register_alias("grassplant", "ebiome:grass")
+minetest.register_alias("grass", "electric_biomes:grass")
+minetest.register_alias("grassplant", "electric_biomes:grass")
 
 minetest.register_decoration({
     deco_type = "simple",
@@ -40,7 +40,7 @@ minetest.register_decoration({
     biomes = {"grasslands"},
     y_max = 200,
     y_min = 1,
-    decoration = "ebiome:grass",
+    decoration = "electric_biomes:grass",
 })
 
 
diff --git a/mods/electric_biomes/init.lua b/mods/electric_biomes/init.lua
new file mode 100644
index 0000000..10262d3
--- /dev/null
+++ b/mods/electric_biomes/init.lua
@@ -0,0 +1,2 @@
+dofile(minetest.get_modpath("electric_biomes") .. "/biomes/grasslands.lua")
+
diff --git a/mods/electric_biomes/mod.conf b/mods/electric_biomes/mod.conf
new file mode 100644
index 0000000..60d975d
--- /dev/null
+++ b/mods/electric_biomes/mod.conf
@@ -0,0 +1,3 @@
+depends = ebiome, ebiometrees
+description = electric game biomes
+name = electric_biomes
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_normal_xjunction.png.kra b/mods/electric_biomes/textures/ebiome_oak_trunk_normal_xjunction.png.kra
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_normal_xjunction.png.kra
rename to mods/electric_biomes/textures/ebiome_oak_trunk_normal_xjunction.png.kra
diff --git a/mods/ebiome/textures/ebiome_grass.png b/mods/electric_biomes/textures/electric_biomes_grass.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_grass.png
rename to mods/electric_biomes/textures/electric_biomes_grass.png
diff --git a/mods/ebiome/textures/ebiome_oak_leaves.png b/mods/electric_biomes/textures/electric_biomes_oak_leaves.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_leaves.png
rename to mods/electric_biomes/textures/electric_biomes_oak_leaves.png
diff --git a/mods/ebiome/textures/ebiome_oak_leaves_simple.png b/mods/electric_biomes/textures/electric_biomes_oak_leaves_simple.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_leaves_simple.png
rename to mods/electric_biomes/textures/electric_biomes_oak_leaves_simple.png
diff --git a/mods/ebiome/textures/ebiome_oak_sapling.png b/mods/electric_biomes/textures/electric_biomes_oak_sapling.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_sapling.png
rename to mods/electric_biomes/textures/electric_biomes_oak_sapling.png
diff --git a/mods/ebiome/textures/ebiome_oak_sprout.png b/mods/electric_biomes/textures/electric_biomes_oak_sprout.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_sprout.png
rename to mods/electric_biomes/textures/electric_biomes_oak_sprout.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_growing_corner.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_corner.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_growing_corner.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_corner.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_growing_normal.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_normal.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_growing_normal.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_normal.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_growing_slice.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_slice.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_growing_slice.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_slice.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_growing_terminal.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_terminal.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_growing_terminal.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_terminal.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_growing_tjunction.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_tjunction.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_growing_tjunction.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_tjunction.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_growing_top.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_top.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_growing_top.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_top.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_growing_xjunction.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_xjunction.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_growing_xjunction.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_growing_xjunction.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_normal_corner.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_corner.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_normal_corner.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_corner.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_normal_normal.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_normal.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_normal_normal.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_normal.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_normal_slice.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_slice.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_normal_slice.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_slice.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_normal_terminal.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_terminal.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_normal_terminal.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_terminal.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_normal_tjunction.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_tjunction.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_normal_tjunction.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_tjunction.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_normal_top.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_top.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_normal_top.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_top.png
diff --git a/mods/ebiome/textures/ebiome_oak_trunk_normal_xjunction.png b/mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_xjunction.png
similarity index 100%
rename from mods/ebiome/textures/ebiome_oak_trunk_normal_xjunction.png
rename to mods/electric_biomes/textures/electric_biomes_oak_trunk_normal_xjunction.png