The relaxed attitude to spectrum use in the USA has come under pressure as a new police radio system in Dallas is interfering with an automated sprinkler system 30 miles away, resulting in brown lawns and dead trees in Plano.

The sprinkler system was set up 15 years ago at a cost of $5 million, and covers 1,200 acres of parkland and trees alongside roads, reports the Dallas Morning News. Officials first noticed the problem back in June when the trees started dying, but it's taken them a while to trace the problem to police radios 30 miles away.

Initially they hoped to be able to negotiate the problem, but a deadlock has left them complaining to the FCC in the hope of a mandated solution.

The cites of Cedar Hill, DeSoto and Duncanville have spent $1.3 million installing their new police radio system, which now has enough range to inadvertently tinker with the sprinklers in Plano as well as water-tower monitoring equipment in Coppell.

Coppell has managed to switch frequency at a cost of only $11,000, but Plano reckon saving their trees is going to cost more than that. With 539 controllers spread around the city, they estimate the cost at around a quarter of a million.

Plano admit they're going to have to change their radio frequency - fauna will always trump flora when it comes to spectrum - but want the three cities to suspend their new system until January, or at least ratchet down the broadcast power, to give them a chance to upgrade.

But the Southwest Regional Communications Center, responsible for emergency response in the three cities, is adamant it must have its system online by November, even at the price of a few dead trees - leading to Plano's complaint to the FCC for spectrum infringement. ®

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