“Mark Trail,” by James Allen. (courtesy of King Features 2016)

IF YOU’RE a regular reader of The Washington Post funnies, you might have recently wondered: Just how does a humble federal worker in Washington end up as a rugged explorer in a widely syndicated comic strip?

Well, from a simple call about a forest fire, the creative sparks flew.

James Allen is the newest cartoonist behind “Mark Trail,” the King Features adventure-soap strip whose title character has been battling wilderness scofflaws for seven decades. And last year, as research for a new comic narrative, he needed some official information.

“I wanted to know what department would respond to a forest fire on a government-owned forest area and what specific vehicles would be used,” Allen recounted to The Post’s Comic Riffs. “It was suggested I call the USDA.”

Allen was put in touch with Abbey Powell, public affairs specialist with the Department of Agriculture’s Animal and Plant Health Inspection Service. She answered his questions, and they got to talking, as one does, about invasive pests.

“We got off the phone, and I began to formulate an idea,” Allen, based in Florida, recalled. “Originally, I was going to have two careless campers leave their campfire unattended, causing a forest fire. The more I thought about it: Why not throw in an invasive species? One highly destructive to trees, and a weakened tree falls on the unattended campfire?”

“Mark Trail,” by James Allen. (courtesy of King Features 2015)

Allen called Powell back, and the conversation led to two narrative decisions:

First, the invasive “villain” would be the emerald ash borer, a pesky beetle that treats firewood like luggage. And second, Powell herself would assume cartoon form.

“We were just talking and we hit it off, and I was enthusiastic about it,” Powell recounted during a conversation in downtown Washington. “He said: ‘Do you just want to be in the comic strip and deliver these messages yourself?’ I said: ‘Cool!’ ”

” ‘Mark Trail,’ since 1946, has been talking about the woods and wildlife and the water — that is its legacy,” said Powell, noting that such a focus readily dovetails with the USDA’s Hungry Pest Campaign, which works to inform the public about invasive species. (“Mark Trail” has included public service announcements in the past, dating back to Allen’s predecessor on the comic, Jack Elrod.)

And so, last year, the federal worker made her debut as Agent Powell in “Mark Trail,” during a run timed to Emerald Ash Borer (EAB) Awareness Week. Now, Powell is making a return trip to the land of “Mark Trail,” as the strip stumbles upon a new pest.

“Mark Trail,” by James Allen. (courtesy of King Features 2016)

“It is the red imported fire ant, which is awful,” Powell said with characteristic enthusiasm. “They bite, and they destroy everything in their path.”

During the multiweek run last year, Agent Powell was a hit with readers, said Allen, as many Googled “Abbey Powell” to see the real person.

“I knew then that she’d be back,” Allen said, and he plans to include her regularly.

Allen says he has not met Powell face to face but hopes to someday. To draw her, he looked at a photo of her and created a “Mark Trail-ized” likeness of her face. “I gave her personality a couple of quirks,” Allen says. “[The character] says “Oh, no!” a lot and, in stressful situations, she refers to herself in third-person.” Allen has even put her in a bikini in a couple of scenes, per the strip’s tradition of winking throwbacks to retro sexism.

The real-life Powell never discussed with Allen how she would be depicted in the strip. “I guess,” the cartoonist said, “she trusted me.”

“Mark Trail,” by James Allen. (courtesy of King Features 2016)