Researchers Getting to the 'Root' of Christmas Tree Problems

Nov 24, 2008

(PhysOrg.com) -- As Christmas tree farmers prepare for their busiest season, researchers at North Carolina State University are studying how to combat a disease that has killed thousands of North Carolina Christmas trees in recent decades.

Current research results suggest that Christmas tree farmers might be able to overcome Phytophthora, a highly destructive plant pathogen that infects the roots of Fraser firs, by using organic mulches.

Researcher Dr. Kelly Ivors says that using mulched organic materials – such as hard wood trees, shrubs and other plant material – as a top application in Fraser fir farms allows microorganisms growing in the mulches to control Phytophthora. Ivors, an assistant professor and extension specialist in the Department of Plant Pathology, is performing the research with Dr. Michael Benson, professor of plant pathology, and graduate student Brantlee Richter.

With the rapid increase in Fraser fir plantings, growers are facing a number of production issues. Most notably, Phytophthora species pose a serious hazard to the U.S. Christmas tree market. Phytophthora root rot has been associated with significant damage to Fraser fir since the 1970s. In North Carolina, annual losses due to Phytophthora root rot are estimated at $6 to 7 million, leaving the long-term viability of the industry in doubt.

"Using chemical applications to treat Phytophthora root rot is very costly – often resulting in farmers spending more money to treat the trees than they make by selling them," Ivors says. "By using alternative methods of controlling this disease, such as mulching, we are helping to fix the problem organically and in a more cost-effective manner."

NC State researchers are conducting tests using the mulching technique in five field sites in Avery, Watauga, Ashe and Mitchell counties. Trees were planted in replicated treatment plots at each site. Soil and mulches are being sampled and analyzed for chemical and biological properties, and rain gauges have been installed to track precipitation. Survival and disease progression will be monitored as long as there are surviving trees in the study sites.

Preliminary results show that average disease ratings are significantly lower in mulched compared to unmulched plots at three of the five sites, Ivors says. She cautions, however, that mulch alone will most likely not be able to provide adequate control of root rot. Development of Fraser fir root stock that resists Phytophthora will likely be needed in Fraser fir production. Current research is focused on understanding how these mulches help control the disease, and what other plant cultivation techniques may be used in combination with these mulches to achieve acceptable levels of Phytophthora root rot control.

"While growers struggle with ongoing problems like Phytophthora root rot on some of their land, they will still get a premium crop of Fraser fir Christmas trees to market this year. Nearly 6 million healthy Christmas trees will be shipped across the eastern United States from the North Carolina mountains," says Jeff Owen, area extension forestry specialist at NC State. "With adequate rain this fall and a good, hard cold snap, the trees will hold up great through the holiday season."

Provided by North Carolina State University

Explore further: Fruit pest's favorite aromas turned against it

add to favorites email to friend print save as pdf

Related Stories

UW scientists probe, attack late blight in potatoes

Sep 03, 2012

(Phys.org)—As the annual potato harvest begins, Wisconsin farmers continue to check their fields for late blight, the ferocious plant disease that caused the 1848 Irish potato famine and fueled massive ...

New website shares information about deadly tree pathogens

Feb 02, 2012

Sudden oak death, Port-Orford-cedar root disease and other deadly tree diseases caused by Phytophthora species (pronounced fy-TOF-ther-uhs) are threatening forest ecosystems worldwide. These microorganisms, which are relate ...

Searching for the perfect Christmas tree

Dec 21, 2010

At the Allen Hill Farm 50 miles east of Hartford, Conn., co-owner Charles Langevin sells hundreds of trees during the holiday season. The Fraser fir is one of the most popular species on the market and is ...

How will tree diseases react to climate change?

Mar 22, 2010

Under a changing climate, patterns of forest disturbance are expected to change, but how will forest diseases respond? A summary of scientific information that addresses this question is now available on the Internet at ht ...

Recommended for you

Fruit pest's favorite aromas turned against it

1 minute ago

A blend of odors that attracts spotted wing drosophila (SWD) flies has been developed into a new lure product for improved monitoring and control of these tree-fruit and berry pests.

Studies steadily advance cellulosic ethanol prospects

41 minutes ago

At the Agricultural Research Service's Bioenergy Research Unit in Peoria, Illinois, field work and bench investigations keep ARS scientists on the scientific front lines of converting biomass into cellulosic ...

User comments : 0