Weyerhaeuser’s fourth quarter earnings plummeted 62% from the same period a year ago to $65 million, the company announced today. Net sales increased 6% to $1.6 billion for the quarter ended Dec. 31.

Fourth quarter 2010 results at the Federal Way, Wash.-based company were bolstered by a $206 million income tax benefit, which boosted earnings out of the red.

For the year, the net earnings at the company fell almost $1 billion to $331 million. Full year results for 2010 included a $1.04 billion income due to the reversal of deferred tax liabilities associated with its conversion to a real estate investment trust. Those numbers were partially offset by $39 million in tax charges related to taxes and benefits involving Medicare Part D. Net sales for the year rose 5% to $6.23 billion.

The company’s wood products division remained in the red during the quarter, but its $80 million operating loss was a $104 million improvement over the same period last year.  The results were aided an 11% increase in sales, to $542 million, and an $82 million decline, to $20 million, in charges related to restructurings, closures, and impairments.

For the year, the segment remained in the red with an operating loss of $248 million, a $73 million improvement over 2010’s results. Net sales for the year grew 3% to $2.28 billion.

Sales volumes for structural lumber rose 5% to 863 million board feet during the quarter, as production volumes increased 7% to 842 million board feet. Sales volumes for the year improved 7% to 3.59 billion board feet. Engineered solid section wood reported sales volumes remained flat at 3 million cubic feet despite a 33% drop in production volumes to 2 million cubic feet during the fourth quarter. Results for the year dipped slightly, as sales volumes fell 1 million cubic feet to 14 million cubic feet.

Fourth quarter sales volumes for engineered I-joists grew by 1 million lineal feet to 30 million lineal feet as production volumes remained flat at 26 million lineal feet. The segment reported a 12% decline in product volumes, to 128 million lineal feet, in its year-end results, as production volumes also fell 8% to 122 million lineal feet.

Oriented stand board (3/8-inch) revealed fourth quarter sales volumes of 516 million square feet, a 26% increase over the same period a year ago, as production volumes reached 541 million square feet, also a 26% increase. For the year, the segment reported a 25% jump in sales volume to 2.01 billion square feet as production volumes improved 24% to 2.13 billion square feet.

Softwood plywood (3/8-inch) unveiled fourth quarter sales volumes of 65 million square feet, an improvement of 8 million square feet. Production volumes jumped by 4 million square feet to 47 million square feet. The segment remained almost flat for full year sales volume at 260 million square feet as production volumes declined 7% to 197 million square feet.

Weyerhaeuser’s timberlands segment reported a 25% increase in operating income to reach $69 million as sales rose 19% to $441 million. For the year, the segment posted an operating income of $481 million, a 73% increase over 2010. Net sales for the year also rose 19% to $1.04 billion.

The company’s cellulose fibers segment reported an operating income of $133 million during the fourth quarter, a 4% dip from the same period a year ago. Net sales increased by 2% to $523 million during the quarter. For 2011, the segment posted a 4% increase in operating income to $433 million, as sales jumped 8% to $2.06 billion.

Fourth quarter operating income in the real estate segment more than doubled to $39 million, even though sales fell almost 10% to $276 million. The segment posted a 13% increase in operating income for the year, to reach $53 million, as net sales slipped 9% to $838 million.

“In 2011 we took full advantage of opportunities to improve our performance in a weaker than expected U.S. housing market,” said Dan Fulton, Weyerhaeuser’s president and CEO. “”through the sale of our hardwood and Westwood Shipping Lines businesses we sharpened our strategic direction, and we remain focused of improving performance to generate superior sustainable returns for our shareholders.”