Rusty dust from spruce trees linked to red tides

• Red goo dust found around the state caused red waters in rim of mystery
By Naomi Klouda
Homer Tribune

Photo courtesy of Catie Bursch - The orange spore samples from spruce trees aren’t harmful, but they do make a streak of color on water and land wherever the wind carries them.

Photo courtesy of Catie Bursch - The orange spore samples from spruce trees aren’t harmful, but they do make a streak of color on water and land wherever the wind carries them.

If proof of a colder, wetter summer was needed in these parts, look no further than the rusty tips on your nearest spruce tree.
And in this case, the burnished dust spread to Kachemak Bay waters and lakes to cast what at first alarmed observers as a possible red tide.
Marine Educator Catie Bursch of the Kachemak Bay Research Reserve coordinates a water sampling program. People around the bay take water samples and send them to her to test for a harmful algae bloom. The idea of her study is to keep tabs on phytoplankton.
“I got a call from a number of volunteers and regular people who were seeing red or orangish water. That is especially alarming to people who may be worried about red tide,” Bursch said. “I want to make clear that red ocean water may, or may not, be a red tide or a toxic shellfish problem, and it could still be toxic with or without red.”
Her interest peaked because she received calls from a broad area.
“That showed that whatever was going on was a huge event. Fish and Game called to ask if I knew about it. I also received a call from the co-operative extension office. People were looking down on it from East End Road, from Seldovia. There were rings of orange around glacier lakes across the bay,” Bursch said. “A friend was up at Juneau Lake, hiking on the Resurrection Trail and told me she saw what looked like fluorescent red paint around the lake.”
Bursch’s initial thought was that it might be pollen.
The first clue came from biologists Carmen and Conrad Field.
“We’d been in the field a lot that week and kept looking at common plants with red pollen. We knew it had to be abundant because it was everywhere,” Bursch said. “Conrad said, ‘Well, there’s this rust stuff on the spruce trees.’ I later looked at it under the microscope and it was the same thing I had seen in the water from Bear Cove to Seldovia.”
One of Bursch’s water monitors is an oyster farmer. He pointed out another good clue when he found the rusty dust on Beluga Lake. That meant it was definitely airborne and not from the marine environment.
The main mystery was solved over the course of two weeks, though even Thursday, Bursch saw the red evidence floating past in Kachemak Bay.
The answer proved to be from a fungus that grows on the new needles of the spruce tree.
“The cool thing is, it has a life-cycle where it has to spend two years on a Labrador tea plant then it spreads its spores on the spruce. You’ll see the Labrador tea plant in wet alpine areas,” she said.
That plant is normally associated with tundra, and in fact, the same fungus, called “orange goo” showed up to mystified Kivalina people way up in Western Alaska, which has no spruce trees.
One of the experts to help solve the mystery was Robin Mulvey, a forest pathologist with USDA Forest Service. Bursch sent her spores from water samples of microscopic photographs. The samples came from Beluga Lake, Seldovia and the Homer Spit.
Mulvey confirmed the origination was the spruce needle rust.
The rust isn’t harmful. In a worst-case scenario, the new needles of this year won’t make it. But the next year, the trees will recover and do fine. They’ve lost a year at worst.
“I learned from the cooperative extension service that fungus loves it below 60 degrees and it likes a wet, cold summer,” she said. “I did get a call last summer; it happened last year as well. But it happened really big time this year. It was such a big spore release, people actually noticed it.”
There was a link to the phenomena elsewhere. An outbreak in Lake Clark National Park was commented on, and in Dillingham, a blog reader wrote that he saw spruce rust during wet, cold summers around the lakes.

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Posted by on Sep 12th, 2012 and filed under Headline News. You can follow any responses to this entry through the RSS 2.0. Both comments and pings are currently closed.

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