The state Game, Fish and Parks Commission passed an emergency ban on June 8.
The rule prohibits people bringing firewood in from areas where emerald ash borers have been found. The ban covers state parks, recreation areas, lakeside use areas, nature areas and recreation trails in South Dakota.
The restriction applies to firewood from places the state Department of Agriculture quarantined because of the insect.
The rule also prohibits firewood from other states.
The commission approved an exception for firewood with a label certifying it has been treated for emerald ash borer.
The insect and larva have been found in firewood.
State camping areas sell firewood for $5 per bundle that is free of ash borers.
Emerald ash borers were found in Sioux Falls in May. It was the first time the invasive species was discovered in South Dakota — the 33rd state in which it has been confirmed.
State agriculture officials quarantined Minnehaha County and parts of Lincoln and Turner counties.
The bug eats into ash trees. The insects are most active from about Memorial Day to Labor Day. They typically need four summers to kill an ash tree.
“Clearly there’s an emergency, based on the information,” Commissioner Gary Jensen of Rapid City said.
State Parks and Recreation Division staff members presented the emergency rule on June 7. The commission unanimously approved a rewritten version on June 8.
The commission also formally proposed a permanent rule with identical language. A public hearing is July 11 in Pierre.
The insect began in Michigan in about 2000, according to Al Nedved, a deputy director for the state Parks and Recreation Division.
Green ash comprise about 25 percent of trees in South Dakota state parks, Nedved said.
Ash trees of almost every type would die unless they have been professionally treated, according to Brenda Sievers, the state’s plant industry program manager.
She said most homeowners aren’t able to apply treatment except on small ash trees.
“It will spread across the state. There’s nothing much we can do about it,” Sievers said. “It could take up to 20 years to spread across the entire state.”
Larvae feed under the bark, she said, and moving logs or even chips from infested trees could further spread the ash borer.
The plan at state parks and recreation areas calls for unlabeled firewood to be placed in a closed container and burned, according to Bob Schneider, a deputy director for the Parks Division. He said the goal is to keep ash borers out of public areas as long as possible so other species of trees have more time to grow.
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