The court may require a conservator to furnish a bond conditioned upon faithful discharge of all duties of the trust according to law, with sureties as it shall specify. Unless otherwise directed, the bond shall be in the amount of the aggregate capital value of the property of the estate in his control plus one (1) year’s estimated income minus the value of securities deposited under arrangements requiring an order by the court for their removal and the value of any land which the fiduciary, by express limitation of power, lacks power to sell or convey without court authorization. The court in lieu of sureties on a bond, may accept other security for the performance of the bond, including a pledge of securities or a mortgage of land.