Marx on how rich farmers gets surplus profit at the the expense of poor peasants

It is true that the peasant, for example, devotes a great deal of labour to his small parcel of land.But this labour in isolated, and deprived of the objective social and material conditions of productivity; it is denuded of them.

the effect of this factor is that the genuinely capitalist farmers are in a position to appropriate a portion of surplus profit; this would disappear, at least as as the present point is concerned, if the capitalist mode of production were as uniformly developed in agriculture as in manufacture........Capital, vol3,