One greenhouse and two field tests were conducted to evaluate the efficacy of Harmony Extra and 2,4-D for post-harvest destruction of cotton stalks. The field studies also investigated the influence of application to shredded versus standing cotton, application timing, herbicide rate and spray volume. Rate (within labeled range) and spray volume had minimal impact on efficacy. Both products performance improved when applied to stalks previously shredded. Harmony Extra performed best after regrowth of two weeks compared to applications made 1 day after harvest/shredding and 1 week after. Savage (2,4-D) performed best when applied at 1 day after harvest/shredding as compared to 1 or 2 weeks. Harmony Extra delayed but did not prevent regrowth and squaring in this test. Savage applied to shredded cotton appeared to provide excellent control of regrowth cotton, but will likely require multiple applications to ‘clean up’ regrowth and control volunteers.