Shares of Weyerhaeuser ( WY) were higher Friday after the company's second-quarter income more than doubled, easily topping analysts' estimates.The Federal Way, Wash.-based manufacturer and distributor of timber, said earnings rose to $369 million, or $1.57 a share, up from $157 million, or 71 cents a share, in the same period last year. Sales rose 20% to $5.9 billion from $4.9 billion. Analysts had forecast earnings of $1.13 a share on revenue of $5.49 billion, according to Thomson First Call. The company said demand for lumber, structural panels and engineered products was up, partially due to the strong housing markets and its effect on prices in the wood products segment. In addition, foreign exchange conditions benefited overseas sales in the pulp and paper division while domestic housing sales drove revenue in the real estate division. Looking ahead, the company said favorable market conditions would continue into the third quarter, however it expects comparatively lower earnings in wood products, the company's prime revenue stream. First Call estimates call for third-quarter earnings of 98 cents a share on $5.39 billion in revenue. Shares of Weyerhaeuser were recently up $1.96, or 3.3%, to $60.62.