Must different categories of grain crops be combined (joined) to complete the Nisab (minimum threshold for Zakat)?
Chapter on Zakat on Crops and Fruits
Al-Mughni
Book of Zakat
Primary text
There are three narrations regarding the combining of grain crops (Hubub). The first opinion, adopted by 'Ata, Mak'hul, Ibn Abi Layla, Al-Awza'i, Al-Thawri, Al-Hasan ibn Salih, Shureik, Al-Shafi'i, Abu 'Ubaid, Abu Thawr, and the People of Reason, dictates that no single type of grain can be combined with another; the Nisab must be met independently for each grain, similar to fruits and livestock. This is because they are distinct species, and the Nisab should be considered separately for each, like fruits.
Supporting text
The second narration asserts that all grains should be combined to complete the Nisab, favored by Abu Bakr, 'Ikrimah, and recorded from Taus. This is supported by the concept that the Prophet (peace be upon him) stated Zakat is due on grain or fruit only upon reaching five Wasq, implying obligation beyond that limit, and because they share the Nisab, rate of output, method of growth, and harvest time. The third narration states that wheat should be combined with barley, and different types of *Qutniyyat* (pulses/legumes) should be combined among themselves. This third view is deemed the correct one by Al-Qadi, and is the Madhhab of Malik and Al-Laith, who further grouped several specific grains as one type based on their use as staple foods.