LANSING, Mich. — More teens are turning to pot while at the same time alcohol use among the same age group has dipped to historic lows, according to an annual national survey of drug use released this morning.

The findings are based on a survey of 47,000 eighth-, 10th- and 12th-graders conducted by the University of Michigan for the National Institute on Drug Abuse.

One of every 15 high school seniors reported smoking pot on a daily or near daily basis, the highest rate since 1981.

One of every nine high school seniors reported using synthetic marijuana, sometimes called Spice or K2, within the previous 12 months.

Marijuana use rose among 10th- and 12th-graders, the study said.

Alcohol use continued a trend of decline dating to the 1980s and hit a historic low for the survey, which began in the 1970s for 12th-graders.

Forty percent of 12th-graders reported drinking in the previous 30 days during the 2011 survey, compared to 54 percent in 1991. Drinking also declined significantly at lower grade levels.