It was a cold day in December 1974 when George Nash hopped in his red Chevy and broke into the Christmas tree industry.

Young and daring, Mr. Nash drove a load of evergreens on his flatbed truck from Vermont to New York City. Propped on the corner of 86th Street and Broadway, he and his partners quickly sold hundreds of them for about $30 each.

But it’s not 1974 anymore, and that old Grinch called economics has made trees pricier for New Yorkers this holiday season. Last year, Mr. Nash sold seven- to eight-foot Fraser firs, the most popular variety, at an average price of $95. They’re going for about $110 this December.

A nationwide shortage of Christmas trees, experts say, is pushing prices to record highs, as vendors scramble to secure enough evergreens and industry experts warn holiday shoppers to buy early before trees run out. A decade ago, amid the Great Recession, growers from Oregon to North Carolina planted fewer Christmas trees; in turn, there are fewer full-grown trees this year.