* Q4 EPS $7.40 per share vs year-ago $6.66
* Nitrogen Q4 net sales down 16 pct
* Sees US corn plantings of 97 mln acres
By Rod Nickel
Feb 19 (Reuters) - CF Industries posted a record-high fourth-quarter profit on Tuesday, but shares eased in extended trading after investors were disappointed by outlook for the full year ahead from the world's No. 2 producer of nitrogen fertilizer.
The company said in a statement that it expects "robust global demand" for nutrients, especially nitrogen, during the first half of 2013, but had little to say about the second half, tempering expectations somewhat after record-high full-year profit in 2012.
CF shares were down 0.3 percent in New York to $217.79 in extended trading. The stock on Friday touched its lowest price in five weeks.
CF said it expects U.S. farmers to plant 97 million acres of corn, the same area as in 2012, resulting in high corn prices and strong fertilizer demand.
Net earnings for the fourth quarter rose to $470.7 million, or $7.40 per share, from $438.9 million, or $6.66 per share, a year ago. Net sales for the Deerfield, Illinois-based company, which also mines the crop nutrient phosphate, fell 14 percent to $1.5 billion.
Analysts had on average expected CF to earn $6.95 a share, according to Thomson Reuters I/B/E/S.
The value of fourth-quarter net sales of nitrogen fertilizers dipped 16 percent to $1.2 billion, while phosphate net sales were flat at $255.8 million, CF said.
Full year 2012 profits were record-large at $1.8 billion or $28.59 per share, as CF benefited from strong demand from U.S. farmers due to high grain prices. The cost of natural gas, a key input in nitrogen production, has shrunk due to a supply glut, boosting margins for fertilizer makers.
Nitrogen is important to boosting yields in corn.
Norway-based Yara International ASA, the world's No. 1 nitrogen fertilizer producer, reported lower year over year quarterly earnings last week, reflecting lower prices.
CF is awaiting a Canadian regulator's approval for it to buy the 34 percent stake it doesn't own in Canadian Fertilizers Limited, Canada's largest nitrogen plant, from Glencore International PLC.