A tall order

Other diseases mimic the symptoms, but Chrissy McTavish, a graduate student at Michigan State University, is the first to have discovered, in 2013, that a fungus called Phomopsis is the real culprit behind tree deaths in both tree nurseries and the natural environment.

Although there are no figures, she said the problem is “widespread,” and though they likely haven´t lost money because of the fungus, it has those in the tree industry spooked.

“It is a huge concern,” said Amy Frankmann, director of the Michigan Nursery and Landscape Association.

“People are calling and saying, ´hey I´m losing my trees,´” Frankmann said. “We have a whole team working on it at MSU.”

Phomopsis Spruce Decline has been spreading throughout the state since the early 2000s. Though it won´t kill a tree in one season, it eats away at the tree for  years, cutting off nutrients and killing the lower branches before squeezing the life out entirely, in the worst cases.

McTavis, who leads the Phomopsis research at the only lab looking into the matter, said she doesn´t knowr how pervasive it is in other states.

“The growers are very challenged,” said Marsha Grey, director of the Michigan Christmas Tree Association. “People are not planting spruce now."

Grey said it hits landscape farmers the hardest.

"What´s weird about this disease is you don´t see the cankers (the brown patches) from the outside of the tree," McTavish said. "You have to scrape really lightly, the top bark off of the limb, and then you´ll see the cankers.”

McTavish and her research assistants brought thousands of spruce trees inside MSU´s sprawling greenhouse labyrinth to infect the trees. She discovered Colorado Blue Spruce were, by far, the most susceptible. Norway Spruce is second most susceptible. Some are resistant, like Myer and Serbian Spruce.

Researchers still haven´t determined whether a fungicide might be helpful for farmers.

McTavish received funding from the Michigan Department of Agriculture and Rural Development, as well as a university funding pool called Project GREENE.