[If] one shells barley, he may shell one at a time and eat it [without separating tithes]; but if one shells [barley] and places [it] in his hand, he is obligated [to tithe it]. [If] one rubs roasted ears of wheat, he may sift [the kernels by tossing them] from one hand to the other and eat [them without separating tithes]; but if he sifted [the kernels] and placed [them] in his lap, he is obligated [to tithe them]. Coriander that one planted for [its] seeds, its greens are exempt [from tithes]; [if] one planted it for [its] greens, it re-quires tithing [of both its] seeds and [its] greens. R' Elazer says: Dill requires tithing [of its] seeds, greens, and stems; but the Sages say: No [species] is subject to the tith-ing of [both its] seeds and greens except cress and garden-rocket.