The Dow Jones printing plant at White Oak, Md., differs at least one way from the company's nine other plants around the country.

"It prints the copy of the Wall Street Journal that the President gets every day," a company production executive said.

Until July 11, it differed another way. It housed the 13 editors, 21 staff writers and clerical employees of the National Observer. But on that date the Observer, a Dow Jones general news weekly, died of economic complications. While it was alive, however, its type was set at White Oak although the paper was printed at three other plants in the East, Midwest and West.

The Observer's demise apparently does not effect some 65 technical wokers who produce, print an mail about 185,000 copies of the Journal daily from the White Oak plant, constructed in 1962 after several years of production at a downtown Washington location.

After press runs starting at 7:30 p.m. and 10:30 p.m., the copies are mailed to subscribers in the District of Columbia, Maryland, Virginia, West Virginia, Pittsburgh and Harrisburg, Pa. Most are delivered with the next day's mail. Some, but not many, reach readers by way of the cocoompany's developing private delivery system.