How trees help clean the air
Series: Agriculture information bulletin ; no. 412; Agriculture information bulletin -- no. 412
Publisher: Dept. of Agriculture, Forest Service : for sale by the Supt. of Docs., U.S. Govt. Print. Off.
Published: 1977
Place of publication: [Washington]
Language: eng
Number of pages: 10
Subjects: Air -- Pollution -- United States; Trees -- United States
Notes: Issued Dec. 1977