diff --git a/src/traits_encoding.txt b/src/traits_encoding.txt
new file mode 100644
index 0000000000000000000000000000000000000000..2d8e74dd3edcd95bd45ec8346c1ab5bcd49365c8
--- /dev/null
+++ b/src/traits_encoding.txt
@@ -0,0 +1,39 @@
+First ID :
+    1 chemical
+    2 physical
+    3 biological
+Second ID :
+    1 C concentration
+    2 N concentration
+    3 P concentration
+    4 Si concentration
+    5 K concentration
+    6 Ca concentration
+    7 Na concentration
+    8 Cellulose concentration
+    9 hemi-cellulose concentration
+    10 hashes concentration
+Third ID :
+    1 Dumas combustion (C/N ratio)
+    2 ICP-MS
+    3 AAS
+    4 Van Soest profile
+    5 Phosphate molybdenum blue method
+    6 XRF
+    7 Oven combustion
+
+ID :
+=2^first_id+2^second_id+2^third_id
+
+Name            first_id    second_id   third_id    id
+C               1           1           1           6
+N               1           2           1           8
+P               1           3           5           42
+Si              1           4           2           22
+Si              1           4           6           82
+K               1           5           3           42
+Ca              1           6           3           74
+Na              1           7           3           138
+Cellulose       1           8           4           274
+hemi-Cellulose  1           9           4           530
+hashes          1           10          7           1154