The normal playing range of a brass instrument includes a definitive stopping note in the instrument's low register. However, players have the ability to manipulate their lips to extend the low range beyond this point; notes sounding below an instrument's normal playing range are called pedal tones. The history of pedal tones in trumpet performance and pedagogy has long been a source of confusion and misinformation. Consequently, this paper also discusses the educational value of using pedal tones, includes a brief history of players and teachers who have formulated pedal tone exercise methods, and examines their use within the six most influential method books that promote the use of pedal tones. The six books are Original Louis Maggio System for Brass by Carlton MacBeth, Double High C in 37 Weeks by Roger Spaulding, Systematic Approach to Daily Practice by Claude Gordon, Trumpet Yoga by Jerome Callet, James Stamp Warm-Ups +Studies by Thomas Stevens, and The Balanced Embouchure by Jeff Smiley.