Within the time required by such order to show cause, any person interested in the subject matter of such petition, including any owner of lands in said irrigation district or the holder of any of its indebtedness whether bonded or otherwise, may appear and move to dismiss, plead, or answer to such petition, or contest the same, in the same manner as in civil actions under the Colorado rules of civil procedure wherein he might be defendant; and for all purposes the nonappearance of any landowner in said district, after due notice of such order, shall be taken as his consent to the granting of such petition and all proceedings had thereon.L. 21: p. 510, § 7. C.L. § 2103. CSA: C. 90, § 552. CRS 53: § 149-3-74. C.R.S. 1963: § 150-3-74.