Nov 04, 2008. /Lesprom.com/. Fitch Ratings announced that it has lowered Weyerhaeuser Co.'s issuer default rating and long - term senior unsecured debt rating to BBB- from BBB. "The current economic situation is proving more challenging to Weyerhaeuser's businesses than anticipated which will now likely extend through 2009 and into some portion of 2010," said Fitch in a statement. It also noted that the decline in the demand for paper and corrugated boxes which have been in negative territory most of the year is also now affecting the pulp markets with prices falling and spilling over into the fluff pulp market. The outlook is negative.