c'est vrai: acre

bushels are measurements for grain, cereals.

In all countries, the measurements varied, even from one part to another

I don't know, I read that even in Spain itself, the measurement varies depending on the location (I suppose it is no longer in use). When I read that, I stopped worrying about being exact in the translated measurement: who knows what dimensions it was referring to.

à la louche : one measuring over 4 acres / about 5 acres ? On ne va pas compter les décimales.
fanega sf
1 grain measure (in Spain 1.58 bushels, in Mexico 2.57 bushels, in the S. Cone 3.89 bushels) grain measure (in Spain 1.58 bushels, in Mexico 2.57 bushels, in the S. Cone 3.89 bushels)
2 land measure (in Spain 1.59 acres, in the Caribbean 1.73 acres) land measure (in Spain 1.59 acres, in the Caribbean 1.73 acres)

XXX one measuring three bushels.