The board of trustees shall be the executive board of such association, and shall be charged with the general management of its affairs. Said board shall adopt by-laws for the association, and change the same at pleasure: Provided, That the by-law for the election of the members of said board of trustees and their terms of office shall be of no effect until the same is ratified by a majority vote of the members of the association. A majority of said board of trustees shall be a quorum for the transaction of business.