Below you can find the This thorny chaparral shrub of the pea family poses one of the worst weed problems in the southwest u.s. Jeopardy Words Answer. The answer to This thorny chaparral shrub of the pea family poses one of the worst weed problems in the southwest u.s. has 8 letters. This clue belongs to the Weeds category and is part of Jeopardy Word Level 1029. If you scroll near the bottom you will find other clues and answers part of level 1029