Sayyidah Aishah (may Allah be pleased with her) said: The Messenger of Allah (peace and blessings be upon him) said: "The zakah of the people of the desert is to be taken at their watering places or in their enclosures."
In one narration it says: "The zakah of the Muslims' wealth is to be taken at their watering places or their enclosures."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الزكاة / 7363