ROCKY POINT, N.Y. (CBSNewYork) — The destructive southern pine beetle is on the move again, discovered for the first time in Nassau County.

As CBS2’s Carolyn Gusoff reported, environmental groups are urging the state to step up the war on the insects before they wipe out thousands of additional trees.

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Golfers at Bethpage State Park have more than greens on their minds. They’re worried about trees.

“We lost a lot of trees in a lot of storms. To lose more by an insect is very bad,” said one golfer.

One single tree has been found infested with the destructive beetle. It’s the first confirmed case in Nassau.

But where this is one, “It means it’s Islandwide. Which we knew it would be,” said John Wernet, forester with New York State Department of Environmental Conservation.

State DEC foresters are in a race to contain the spread of the tree-ravaging insects, which mysteriously moved north from New Jersey and made its first appearance in Suffolk County last fall.

So far, 3,000 trees have already been chopped down across Suffolk’s south shore.

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On Monday, mapping the infestation began in the north in Rocky Point. A Dozen expert foresters arrived from as far away as Canada to survey and help educate the public.

“To try to help people identify this little beetle because there are all kinds of insects in the woods,” said Maine forest ranger Kent Nelson.

But environmentalists worry about the pace. The Pine Barrens protect Long Island’s drinking water supply.

“They’re doing the right thing, but they’re doing it in tiny increments. At this rate, we’ll will have lost it before we’ve even have begun the fight,” said Dick Amber, with the Long Island Pine Barrens Society.

Others say the effort is understaffed and underfunded, and needs to expand into private land.

“We’re probably looking at the need for millions of dollars,” said Executive Director of the Central Pine Barrens Commission, John Pavacic.

Some state legislators say they’re considering legislation for a more comprehensive plan of attack, including financial aid to help homeowners remove infested trees, before this turns into a situation of too little, too late.

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Until recently, New Jersey was the northern most point of infestation. The insects destroyed 50,000 acres of trees there. That’s the size of Long Island’s entire Pine Barrens core.