«فيما سقت السماء والعيون العشر وفيما سقي بالنضح نصف العشر»
The Prophet (peace and blessings be upon him) said:
"On what is watered by rain and springs there is one tenth, and on what is irrigated with buckets there is one twentieth."
Hadith Referenceصحیح الجامع الصغیر / حرف الفاء / 4272