Fewer yellow signs are popping up in Los Angeles this spring.

Those placards, which direct cast and crew members to a location shoot, normally sprout like wildflowers in March and April, as pilot production reaches full bloom.

But despite an uptick in broadcast pilot orders this year, Los Angeles — and New York, too — is increasingly losing out to a wide variety of locales across the country.

The trend is most notable in drama, as a majority of pilots are being shot this spring in places such as Chicago, Atlanta, Hawaii, New Mexico and Dallas.

The runaway champ may be CW, which is taking a page from cable and shooting all but one of its pilots in Canada.

“It’s simply about the economics,” one studio exec says. “We all have to take our shows abroad and get the benefits of tax rebates.”

If an average drama costs between $2.7 million and $3.7 million an episode, and a network is paying between $1.5 million to $1.7 million in license fees, that 10% to 25% tax rebate suddenly looks very good to a studio exec.

“That makes a difference between these shows taking terrible deficits or being somewhere in the break-even range in season one,” one exec says.

That extra $300,000 to $750,000 back is also critical given the uncertainty of both the international sales and domestic syndication markets.

A few recent megadeals aside (like USA’s recent “NCIS: Los Angeles” acquisition), “no one has a lot of faith in the syndication market,” one exec says. “And the DVD market is terrifying.”

Film L.A., which tracks production in Los Angeles County, is a bit more optimistic this pilot season. The agency notes that 59% of overall TV pilot production is being filmed in L.A., up a tick from last year’s 57%.

But that comes following a dramatic five-year slide in the number of pilots produced in Los Angeles. The agency noted that the number of pilots produced here has dropped 42% between 2004 and 2009.

And according to a Film L.A. study last year, that meant that estimated pilot production spending in the L.A. region dropped from $309 million in 2005 to $207 million in 2009.

“The availability of financial production incentives is a key factor influencing where pilot producers choose to film,” the study noted.

What’s more, the number of drama pilots shot in Los Angeles continues to slide. This year, according to most recent pilot-tracking data, just 14 out of 43 broadcast drama pilots are being shot in Los Angeles, with zero in New York. That leaves 29 in other locations (including nine in Canada). Last year, 17 out of 39 broadcast drama pilots were filmed in L.A.

Comedy fares better, as most half-hours are still shot on soundstages in L.A. And, according to one exec, network and studio execs are more involved throughout the table read and run-through process on sitcoms, which are much more likely to go through last-minute script changes.

“On a one-hour, you maybe do a table read, but then it’s gone,” that exec says. “After that, it doesn’t matter from a creative standpoint whether you’re shooting five miles away, or 500 miles away. You’re seeing the dailies the next day either way.”

Beyond economics, studios and producers may shoot a pilot elsewhere to add a dose of authenticity to the project. ABC’s “187 Detroit” may be the season’s oddball (shot in Atlanta), but CBS’ “Hawaii Five-O” actually will be shot in Hawaii, while Fox’s Texas oil-business drama “Midland” will be done in Dallas.

For Shawn Ryan, it was important to actually film his Chicago-set Fox cop drama “Ride-Along” in Chicago.

“I wanted to delve into the city, its politics and history, and I wouldn’t want to try to do that in Los Angeles,” he says.

Given the incentives being offered by Illinois (put in place by ex-Gov. Rod Blagojevich), 20th Century Fox studio was quick to sign on to the Chicago shoot, Ryan says.

There are actually so many pilots being shot in the Windy City at the moment that there became a scramble to find cast crew members. Because “Ride-Along” got an early greenlight, Ryan says he believes he was able to secure Chicago’s A-list.

As for Ryan’s FX drama, “Terriers,” that project is shooting in San Diego because producers found a beach community that fit the show’s setting.

With so many pilots shooting outside of Los Angeles, casting was a challenge on the drama side, execs admit. Ryan says several high-profile thesps didn’t want to be considered for “Ride-Along” because they have children, and didn’t want to move away from Los Angeles.

“We found Jennifer Beals, who not only wanted to do the show, but was from Chicago and wanted to move there with her children,” he says.

As for the difficulty of shooting a show so far from his Los Angeles base, Ryan says Skype teleconferences help, and he also sends writers to spend a week on set as their episode is shot.

It’s still not necessarily an ideal situation, says one exec, who adds that all things being equal, he’d prefer to keep productions in Los Angeles.

“I feel horrible for the local, below-the-line community,” one TV insider says. “(And) I feel bad for California and (governor Arnold) Schwarzenegger and the mayor. But politically, it’s very difficult for them to give us a tax credit.”

There is a chance, of course, that some of these runaway pilots will return to Los Angeles to shoot, should they get a series order. But there are also L.A.-shot pilots that could wind up being produced elsewhere if picked up to series, insiders say.

That includes shows set in Los Angeles. ABC’s L.A.-set “Cutthroat” will likely shoot in Dallas, for example.

There’s still a chance productions could migrate back to L.A., if states stop renewing their tax incentive programs as they expire. But so far, most of those arrangements have been renewed, or still remain attractive to studios.

“If Los Angeles was less expensive, they’d shoot here,” an exec-turned-producer says.