Oregon recently gave a Clark County growth industry quite the trim.

Since retail marijuana sales started on the far side of the river in October, sales here have taken a big hit. But local retailers are staying optimistic.

“They’ve all said it’s doom and gloom for Clark County,” Main Street Marijuana co-owner Ramsey Hamide said. “We’re confident in where we are now and our long-term growth prospects.”

Sales were expected to fall in the county after marijuana was officially legalized in Oregon in July. But that actually led to a summer-long spike in sales, according to Washington state data.

Oregonians apparently crossed the Columbia River in droves to celebrate their new freedom, even though it is still federally illegal to cross state lines with marijuana.

But last month, when Oregon started allowing medical dispensaries to sell to recreational customers, Clark County stores saw revenues dive from nearly $1.8 million in September to $1.1 million in October.

“It was an artificial spike after Oregon didn’t have an outlet between July 1 and Oct. 1,” Hamide said. “All the Vancouver shops, ourselves included, all went back to what we had in June, pretty much.”

The Office of Financial Management said that Clark County recorded 12.8 percent of the state’s total sales by quantity in September. By the end of October, that had fallen to 7.6 percent. Clark County is home to 6.4 percent of the state’s population.

That’s about where county sales were in June, in terms of state market share. Hamide says retailers are simply back on the same growth track they were on.

“We’re still in a pretty healthy market,” he said.

Full recreational retail stores could start opening in Oregon late next year, and marijuana will start being taxed Jan. 1.

Hamide said Washington’s head start should keep business rolling smoothly, even with the new competitors.

“We still have a competitive advantage over Oregon for the next year until they’re able to sell the same products we are,” he said.