Congratulations on your victory in the Hunger Games! You had only a knife but the element of surprise was on your side when you caught the remaining tribute (a Career) looking for you. They only had a bow and arrow so they were bound to lose the fight. Sure enough, you won. You returned home to your family, glad to be alive.
District Seven provides lumber for the Capitol, and the tributes of District 7 are known to be good with axes. District 7 is apparently covered in large portions of pine forest.