At the height of the nation’s snowboard craze, Rod Rice was a “blazin’ raisin” — an older dude who loved to bomb the slopes at breakneck speeds.

That is, until he wiped out and dislocated his shoulder on a trip to Canada. The 65-year-old engineer still loves to carve fresh powder, but now he does it on a pair of extra-wide skis.

“I’m not planning on going back to snowboarding,” said the Lakewood, Calif., grandfather.

Once the king of the mountain, snowboarding is on the down slope.

The rage that transformed the nation’s ski resorts and planted such terms as “jib,” “face plant” and “biff” into America’s lexicon is cooling off partly because many older riders are shifting to new, easier-to-ride skis to preserve their aging bodies.

Sales of snowboards and snowboard equipment have slipped 21 percent over the last four years, while sales of skis have climbed 3 percent in the same period, according to SnowSports Industries America, a trade group that tracks the $3.5-billion snow sports and apparel industry.

Baby boomers aren’t the only ones bailing. Last season, alpine skiing replaced snowboarding as the most popular snow sport among kids ages 6 to 17, according to the trade group. That’s the first time in nearly a decade and a troubling sign for snowboard makers battling for a key demographic.

The once-hip, ultra-extreme sport may have lost its allure when Mom and Dad picked it up a few years ago.

“Kids don’t want to do what their parents do,” said Chris Riddle, a spokesman for Snow Summit and Bear Mountain ski resorts near Big Bear Lake. He said he’s seen an increase in skiers in the terrain park typically dominated by snowboarders.

A snow-loving member of the millennial generation, 17-year-old Arten Yegikyan from La Crescenta, Calif., tried snowboarding on Bear Mountain a few months ago. He said he gave it up because he felt beat up and frustrated when he was done.

“It felt like you had no control over the direction you are going,” said Yegikyan, who now prefers skiing.

The limitations snowboarders face in powder and flat terrain are a reason Kristy Chocholaty, 35, of Truckee, Calif., has given up on the sport. She jumped on the snowboard bandwagon in the late 1990s. “I wanted to check it out because so many people were snowboarding at the time,” she said.

But she said she gets frustrated when she tries to keep up with her skier husband and gets stuck in places that he can simply push through with his poles.

Ski and snowboard manufacturers acknowledge the factors weighing on snowboards. But they predict sales will rise again as manufacturers push new board designs that will be easier and safer to ride.

“Like anything else, you will see the snowboarding trend wax and wane,” said Nick Castagnoli, a spokesman for Rossignol Skis USA, a longtime manufacturer.