Is barley classified under Ribawi items with surplus, or is it in the same category as wheat?

Barley and wheat are two independent categories regarding riba al-fadl (riba of excess), and this is indicated by the hadith of Ubadah ibn al-Samit: "Gold for gold, silver for silver, wheat for wheat, barley for barley, dates for dates, and salt for salt—like for like, measure for measure, hand to hand. If these categories differ, then sell as you wish, provided it is hand to hand." Ibn Hajar mentioned that Al-Bukhari explained Salman ibn Harb's saying, "There is no usury except in deferment," by stating: "This, in our view, applies to gold and silver, and wheat for barley, if there is an excess, and there is no harm in it hand to hand, but there is no good in it if deferred."