In American history, black walnut trees like soil with good drainage at the bottom, especially in the Appalachian mountains and the Midwest. However, its natural distribution extends to Vermont, Michigan and Great Lakes in the north, northwestern Florida and Zoya in the south, and eastern South Dakota, northeastern Nebraska, western Oklahoma, Kansas (abundant in some flora) and central Texas in the west. However, walnut trees do not grow in the Mississippi valley or delta, and the southern States along the Gulf Coast or Florida Peninsula are not suitable for its growth. American Hardwood Export Council published and distributed "American Hardwood Approved South" about the physics of black walnut for free.
Its performance, processing performance and wide application range are introduced for readers' reference.
The white wood of American black walnut is milky white, the heartwood is light brown to dark brown, and there are often purple cracks and cracks.
Dark stripes. Walnut usually has a straight grain, and sometimes it has a wavy or curved texture, which makes it attractive.
, decorative graphics. Walnut is a tough hardwood with medium density, bending strength and breaking strength.
Moderate, low rigidity, good steam bending performance.
Walnuts are easily processed by hand tools and machinery. Nails, screws and glue have good fixing performance and excellent oiliness.
Paint and dye are retained, and excellent surface can be obtained after polishing. Walnuts dry slowly and need careful care.
To avoid drying and aging. Walnut has good dimensional stability and is evaluated as a heartwood with extremely high corrosion resistance.
Solid wood. Its white wood will be eroded by pink column beetles. Historically, walnut grading specifications were 6-inch and 7-inch FAS and FASIF(FAS grade was designed for drums.
Encourage the better use of wood, so it is graded according to the defective foundation, not according to the clean wood cutting foundation.
. The super grade of walnut is usually decided by the buyer and the seller.
The timber association's inspection regulations also allow such installation. The only difference between these varieties is the soil, latitude and climate conditions in the growing area. Growth rate is not
The same tree produces very different plates. Within the range of walnut growth, there can be a growing season from north to south every year.
The department's 140 days range from 280 days at the southernmost tip of West Florida. In addition, the average temperature is 7 degrees Celsius in the north and 7 degrees Celsius in the south.
The temperature is 19 degrees Celsius. At present, the logging of black walnut is mainly used as veneer and sawn timber for furniture, cabinets and joinery products, although
It is increasingly used to produce floors and has been used to produce gun butts. However, walnuts first developed in the United States.
It's quite interesting to use. Although walnut is the main wood of veneer sliced logs and sawn timber, it produces edible walnuts and walnuts.
It is extremely important to eat more inedible walnuts and nuts. During the second world war, the aircraft piston was made up of
The nut shell was cleaned by a spray gun. This method is also applicable to the automobile industry, where manufacturers use fruit shells as teeth? q
Uot deburring. Crushed shells are also used to clean jet engines; Drilling as an oil drilling activity
Mud additive; As a filler of explosives; As an anti-skid agent for automobile tires; As a blank space for removing paint.
Gas compressed propellant; As a filter for the scrubber in the chimney; It can also be used as a flour additive in various pesticides.
. It can be seen that the motivation for the expansion, improvement and innovation of this variety has always been great!
Today, one of the most important uses of walnut is the application of walnut veneer and solid wood sawn timber. This is similar to other tree species.
In particular, acacia, maple and oak are in sharp contrast.
American walnut can be replaced by American eucalyptus because the wood grain pattern of the latter is similar. However, eucalyptus
Must be dyed to match walnut. American black walnut has always been very popular in the international market, but due to the light-colored wood movement in the 1920s and 1990s.
, that is, the prevalence of light-colored hardwood, fell out of favor for a while. Italy lacks sufficient supply of so-called local raw materials.
Since 1998, it has been an important exporter of American black walnut. Recently, black walnut has regained its luster, also in Asia.
Europe, especially China, has found new markets. In the United States, there is a considerable supply of walnut sawn timber, but there are geographical restrictions. As mentioned earlier, this
Tree species love pets again, which makes the supply of kiln dry boards ready for delivery feel some pressure. This is the price.
Can be reflected in the world. At present, the stock of some specifications of plates is limited, but the inventory of sliced veneer is sufficient. moustache
There are many forms of peach regeneration, mainly the seeds buried by squirrels but not dug up. After 20-30 years, plants will be planted.
Reach the peak, lasting 100 years. The temperature in winter causes seeds to germinate in spring, and the vigorous growth of taproots makes
The survival rate is very high.
Walnuts grow faster than oak trees, and stumps will sprout after forest fires. Grafting and budding techniques can now get 8.
0- 100% success rate. Walnut is more resistant to waterlogging than other tree species such as cherries, but it is afraid of being blocked by sunlight, so it is related to
Fast-growing tree species such as Liriodendron need to stay out of the competition. Artificial forest cloning technology has been developed, and there are three kinds of trees.
Wood asexual propagation plants have been patented by Purdue University. one of
So they are chosen because their trunks are straight, they have strong resistance to carbon maggot disease, or they have leaves in late spring.
The impact of logging on the environment
Walnut provides food for wild animals and humans, and humans are also broad-leaved in the eastern United States because of their natural dispersion.
Timber forest is an integral part of the biological chain. Walnut rarely exists alone, but with many other tree species.
Growth, especially oak, maple and Liriodendron. Cut down mature trees, evacuate young trees, quality
The removal of bad trunks is a process of selective cutting and regeneration, which leads to the beginning of 1945.
The result of increasing timber reserves year by year. The continuous development of large-scale plantations has also provided this tree species with other Americas.
Another characteristic that hardwood usually doesn't have.
Example of installation of public facilities
In Britain, there are countless examples of the application of American black walnut. The most famous is St Paul's Cathedral.
New podium and new joinery products of Asimolin Museum in Oxford.
White edge: the wooden part from bark to heartwood, the color is obviously different from concentric wood, and the color is white. It is usually called white edge in the industry. According to the classification of American Broad-leaved Wood Board Association, this defect is included in the net drawing, and there is no grading standard.
Stump: A swirling or twisted knotless wood grain. This defect is also included in the net drawing according to the classification standard of American hardwood board association, and there is no grading standard.
Mineral stripes: various colored stripes from olive green to dark brown, usually in the same direction as the texture.