Barking up the wrong tree is an idiomatic expression in English, which is used to suggest a mistaken emphasis in a specific context. The phrase is an allusion to the mistake made by dogs when they believe that have chased a prey up a tree, but the game may have escaped by leaping from one tree to another. The phrase means to mistake one's object, or to pursue the wrong course to obtain it.

In other words, "if you are barking up the wrong tree, it means that you have completely misunderstood something or are totally wrong."

Historical usage

• 1833 – "It doesn't take a Philadelphia lawyer to tell that the man who serves the master one day, and the enemy six, has just six chances out of seven to go to the devil. You are barking up the wrong tree, Johnson." -- James Hall, Legends of the West, p. 46.
• 1833 – "I told him that he reminded me of the meanest thing on God's earth, an old coon dog barking up the wrong tree." -- Sketches of David Crockett," p. 58. (New York).
• 1834 – "[The Indians] to use a Western phrase, barked up the wrong tree when they go hold of Tom Smith."
• 1836 – "You've been barking up the wrong tree, cried the Ohioan." -- Knickerbocker Magazine, p. vii. 15 January 1936.
• 1838 – "Instead of having treed their game, gentlemen will find themselves still barking up the wrong tree." -- Mr. Duncan of Ohio in the United States House of Representatives
  United States House of Representatives
  The United States House of Representatives is one of the two Houses of the United States Congress, the bicameral legislature which also includes the Senate.The composition and powers of the House are established in Article One of the Constitution...
  
  , July 7: Congressional Globe, p. 474, Appendix.
• 1839 – "The same reckless indifferenece which causes a puppy to bark up the wrong tree. -- Chemung (NY) Democrat, September 18. 1839.

Sources

• ___________. (1886). Barking up the wrong Tree; a Darkey Sketch in One Act and One Scene. New York: Dick & Fitzgerald. OCLC 20640219
• Boye DeMente, Lafayette. (2007). Cheater's Guide to Speaking English Like a Native, Rutland, Vermont: Tuttle Publishing. 13-ISBN 978-0-804-83682-1/10-ISBN 0-804-83682-5; OCLC 148660284
• Conald, James. (1872). Chambers's English Dictionary: Pronouncing, Explanatory, and Etymological with vocabularies of Scottish words and phrases, Americanisms, &c. London : W. & R. Chambers. OCLC 37826777
• Thornton, Richard H. and Louise Hanley. (1912). An American glossary. Philadelphia: J.B. Lippincott. OCLC 318970
• Walsh, William Shepard. (1909). Handy-book of Literary Curiosities. Philadelphia: J.B. Lippincott. OCLC 1032882