Frank King, frequent contributor and “the cardiac comedian” (http://thefunnyhealthcarespeaker.com/) , heard this one on the Rachel Maddow show. A former radical Islamist was the guest who uttered this malaphor a few times. I believe it is a mash up of “stopped in its tracks” (stop someone or something suddenly and completely) and “root out” or “pulled out by the roots” (completely eradicate). Both phrases mean to stop something completely so it is also a congruent conflation. A big thanks to Frank for hearing this one and sending it in!