Ever wonder how that Christmas tree that sits flashing at you in your living room got there? Many thousands of farmers in the Northwest grow the trees, and there'ês plenty of science that goes into making sure that they stay green, robust, and radiant all through the season.
The man who can tell you all about these trees is Gary Chastagner, a Puyallup-based researcher. Working at Washington State University'ês Research and Extension Center, the professor of plant pathology is among a growing number of tree scientists who assist the country'ês 15,000 Christmas-tree growers. They have sought to find out which varieties are the hardiest, most resistant to disease, and equipped with the longest-lasting needles.
The Pacific Northwest provides 40 percent of America'ês Christmas trees, and one third of all the world'ês holiday conifers. Washington and Oregon growers harvest more than 10 million Christmas trees annually, and sell them at a wholesale value of $176 million, according to the Pacific Northwest Christmas Tree Association, which has been guiding the industry since 1955. Half the Northwest trees go to California. Other major growing regions are in the Northeast, the Midwest, and North Carolina, where growers vie for a part of a US market in which 35 million buyers choose among 15 natural varieties.
Chastagner used to work on turf grasses and ornamental bulbs before being drafted to work on Christmas trees. The problems of growing Christmas trees are complex, largely because firs were never intended as indoor trees. If you go and buy a tree the day after Thanksgiving and expect it to still look fresh and hardy on New Year'ês Eve, you'êre asking for a lot. But Chastagner and his colleagues, in cooperation with scientists and industry partners in eight states and four foreign countries, focus on needle retention and on identifying genetically superior trees.
To start with the basics: Needles fall off trees when they dry. For that, suggests Chastagner, try the obvious: watering. Firs require three-quarters of a gallon a day, far more than most commercial tree stands hold. Nothing beats sticking your tree in a medium-size trash can filled with rocks and water.
Then it gets complex. In a hut at the WSU facility, where hundreds of Christmas trees hang by string from the ceiling, some into cans of water, some to the concrete floor, Chastagner approaches a rather yellowed tree and says: "You get tremendous spider-mite damage on Fraser firs, like that, but very little on this one here, which is a grand fir, and is typically grown here, but it doesn't have the needle retention we'd like."
The close confines of the hut concentrate the familiar aroma of fir sap. Chastagner discusses shoot blight, twig aphids, woolly adelgids, frass, needle necrosis, stem canker, and root rot, which cause discoloring of needles, branch distortion, and diebacks. His disease and pest research focuses on combating root rot, needle necrosis, Grovesiella canker, spider mites, and twig aphids. He also seeks to reduce populations of yellowjackets and other insects on trees that restrict export markets. To breed trees with the best qualities, the researchers are collaborating with colleagues in Scandinavia, testing trees from there, Turkey, the Republic of Georgia, and other nations.
The basics of the science are relatively straightforward. Few buyers will opt for a tree with gaps; growers combat those by shearing trees during the summer so that shoots have more room to bloom, filling in spaces. Surveys have shown that needle retention is most important to Americans. Europeans are less fussed about that, because they generally display trees for only five or six days.
Chastagner will develop profiles for the suitability of various varieties to particular growing environments, such as sandy or wet soil. Researchers have learned, for example, that the Canaan fir, from the Canaan Valley in West Virginia, fares particularly well in wet soils. And he will bear in mind how long it will take various kinds of trees to grow in different regions, noting 'êIt'ês one thing to have a tree that has good needle retention but if you can'êt grow it in reasonable time, it'ês not much use to the industry.'ê
Fashions also change. Over the last 60 years in the United States, Christmas trees have come to be shaped and sheared like pampered poodles. Far preferable, in Chastagner'ês opinion, is the layered look favored in Europe, 'êtrees that tend to be more natural in appearance.'ê Scotch pines, cultured and dense, were once all the rage, but now are less in demand since, as they dry, says Chastagner, 'êthey'êre prone to have very sharp needles.'ê
All the research shows that in the Pacific Northwest, as Chastagner puts it, 'êthe noble fir is the Cadillac of Christmas trees. It has stiff branches and good post-harvest qualities.'ê Equally as important, in other parts of the country, is the Fraser fir. 'êThose two species have increased tremendously in the market place and have displaced less-desirable species such as the Scotch pine and the Douglas fir,'ê although the latter remains important, he says.
Meanwhile, the artificial tree is gaining ground. It now accounts for 68 percent of American Christmas-tree sales, an increase of 150 percent since the late 1950s. During that period, the U.S. population has doubled, yet annual sales of natural trees have increased only from 30 million to 35 million (compared with 60 million in Europe).
These trends drive Chastagner and his colleagues to maximize the fortunes of organic trees. For example, they learned that most degradation of Christmas trees occurs on retails lots. Now, retailers often display trees in water or mist them at night to maximize moisture and needle retention. The researchers also showed that commercial preservatives maintain trees on lots no more effectively than water. That prompted some jurisdictions to stop requiring retailers to treat trees with harmful fire retardants.
All the efforts of Chastagner and his fellow researchers have been geared towards making growers and retailers more aware of what makes for good Christmas trees. He says. "If you've been around any Christmas-tree lots, you realize that there are people in the retailing business who have been at it for a long time; they go to professional meetings, and they keep up on stuff."
