-- From Times staff reporter Sara Jean Green:

Pot busts don't get any easier than this.

A 68-year-old California man was arrested late Thursday night after State Patrol troopers pulled him over in Kirkland and found 31 pounds of pot in the backseat.

The traffic stop came after a motorist called 911 around 11:30 p.m. Thursday to report an erratically-driven Ford Excursion on northbound Interstate 5 in Tukwila, said Trooper Dan McDonald. The other driver remained on the phone with a dispatcher and followed the Excursion across the 520 Bridge and then north on Interstate 405, McDonald said.

"It's outstanding -- we love that," he said of the other driver's willingness to follow the Excursion until troopers could stop it.

The Excursion was speeding up and then slowing down, making unsafe lane changes and weaving, McDonald said. The trooper who stopped the Excusion "could smell an overwhelming odor of marijuana" and noticed the driver displayed signs of being under the influence of marijuana, he said.

During a search of the man's SUV, the trooper found 31 pounds of marijuana packaged in several clear, one-gallon, plastic bags, McDonald said. The bags were sitting on the Excursion's back seat, he said.

The man also had rolls of $20 bills in his pockets ­-- $2,700 worth, McDonald said. A pipe was also found in the vehicle, he said.

The money, the pot and the man's vehicle were seized and he was arrested on suspicion of felony possession of marijuana and possession with intent to deliver, McDonald said.