UPDATE 2-Plum Creek trims outlook amid weak lumber demand

(Adds details on outlook, updates share move)

NEW YORK, April 1 (Reuters) - Plum Creek Timber (PCL.N), which owns vast tracts of timberland in the United States, cut its first-quarter and full-year earnings forecasts on Tuesday due to delays in land sales and weak demand for lumber.

In recent months, the company and many of its peers have been badly hurt by the slump in the U.S. housing market. Plum Creek's share price has declined about 10 percent over the last six months.

The Seattle-based company said it now expects first-quarter earnings of 18 cents to 22 cents a share, down from a prior forecast of 26 cents to 31 cents. Analysts, on average, were expecting 28 cents a share, according to Reuters Estimates.

Plum Creek said it lowered its forecast because certain land sales anticipated in the period did not materialize.

It now expects real estate segment revenue of $50 million in the first quarter, well below its earlier forecast of $75 million to $85 million.

It forecast full-year earnings of $1.05 to $1.30 a share, down from an earlier forecast of $1.15 to $1.40. Wall Street is expecting $1.26 a share.

The company said that with residential construction activity touching low levels not seen since the early 1980s, it expects demand for sawlogs -- logs large enough to be carved into lumber at a sawmill -- to remain weak in many markets.

Plum Creek expects real estate sales to be seasonally weighted toward the second half of the year, and it continues to expect real estate segment revenue for the full year to be between $320 million and $340 million.

The company said it plans to release its first-quarter earnings after the market close on Monday, April 28.

Shares of Plum Creek were down 1 percent at $40.26 in morning trade on the New York Stock Exchange after falling as low as $38.84 in pre-market dealings. (Reporting by Euan Rocha, editing by Gerald E. McCormick and John Wallace)