Are Joe and Stan Low of Beavercreek, Oregon mainly Christmas trees growers or black walnut growers? The answer is both, but the question seems to be an amicable, on-going debate between father and son. Forestry, agriculture and agroforestry all coexist profitably on their 900 acre Highland Farm in the northern Willamette Valley.
A native of West Virginia, Joe learned the value of black walnut timber during the Depression years. After moving to Oregon in 1943, he began a 30-year career in the sawmilling business, cutting primarily native Douglas fir in the local area. His interest in black walnut remained, prompting him to plant some of the first stands of walnut for timber in Oregon 35 years ago. Starting about 20 years ago, Joe and his son Stan have established 50,000 black walnuts on over 200 acres of black walnut/Christmas tree alley cropping or vice versa.
In Joe’s experience, eastern black walnut grows well in the Willamette Valley. The only disease he has encountered is walnut anthracnose, but he says it is less of a problem in Oregon than in the warm humid climates of the Midwest. Weed control is the main cultural practice, Joe said, along with training during the early years of establishment to correct stem form deficiencies.
At Highland Farm, black walnuts are planted on a 15 X 15 ft. spacing (about 200/ac) with either Douglas fir or noble fir as the short-rotation intercrop. About 25 years after planting, Joe plans to thin the walnut to a final crop spacing of 30 X 30 ft. (about 50/ac). His aim is to produce a straight, 4 ft. diameter log in about 75 years that will yield high-value timber or veneer.
Fast-growing and commercially-valuable Douglas fir is co-dominant with walnut and serves as a “crowd tree” to force the walnut to produce tall, straight stems. In stands where Joe has simultaneously planted walnut and Douglas fir at the same initial spacing (200/ac), he will be able to choose at the time of first thinnings whether to leave the walnut or the Doug fir to grow as the final timber crop.
In other stands, Joe has interplanted the relatively-slower growing but more valuable noble fir, planted on 5 X 5 ft. spacing, with walnut on 15 X 15 ft. centers. Noble fir is ready for harvest as Christmas trees in 8-10 years, compared to about 7 years for Douglas fir Christmas trees.
In all of his plantings at Highland Farm, Joe has planted nuts rather than seedlings. Experience has shown him the importance of direct seeding to develop a strong taproot that will produce hardy trees better able to cope with Oregon’s dry summers. Joe has scouted all the best walnut trees in the local area and each year collects nuts for planting from selected trees. He either plants the nuts in the fall or stratifies them during the winter for spring planting. The alley cropping enterprise at Highland Farms is a good example of the extra management and economic tradeoffs inherent in agroforestry verus monoculture. According to Stan, who manages the Christmas tree operation, there is a economic cost to alley cropping. Labor costs to shear Christmas trees intercropped with black walnut are higher because extra care must be taken to avoid damage to the walnut, which slows the work rate. Weed control during the early years of establishment is also more problematic when firs and walnuts are mixed.
As the walnut trees mature, they compete for light with the Christmas trees. Stan has observed that shade will degrade the needle length and color of the firs compared to open-grown trees, and therefore decreases their quality and potential price as Christmas trees.
He suggests that increasing the initial spacing of the walnuts would help overcome these problems. If the walnuts were planted in every 4JD or 5JD row instead of every 3H@ row, the firs would have more light available to develop into higher quality Christmas trees. Shearing costs would also be reduced, he said, by allowing more space for the firs.
Whatever the ideas for future changes in initial spacing and management, it is obvious that the Lows have a very large resource of valuable hardwood timber slowly maturing to harvest age. Joe anticipates that this resource will create markets for his timber both locally and overseas, especially in Europe. There will also be a substantial nut crop that could be processed on-site or shipped to processors in California. Joe is also thinking about other potential intercrops such as ginseng that could be produced among his walnuts after the Christmas trees are harvested.