The National Arboretum for research and education. - [Washington, 1964] - [12] p. (incl. cover) illus. 20 x 27 cm. Cover-title. LCCN: agr64000272 Subjects--Geographic Terms: National Arboretum (U.S.) LC Class. No.: QK479 / .U5 Gov. Doc. Class. No.: A 77.502:Ar 1/2