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Everything you could want to know about Genetically Superior Black Walnut Trees

RESEARCH
DEVELOPMENT
CHARACTERISTICS
PROJECTED VALUE
HOW IT ALL BEGAN
HOW MUCH ARE THE TREES WORTH?
THE PRESENT
ASSUMPTIONS

HOW TO GET THE BEST PRICE
IS FAST-GROWING WOOD LESS DESIREABLE?

MAXIMIZING THE RETURN ON PLANTATION INVESTMENT
PURDUE UNIVERSITY RESEARCH
WHERE TO PLANT
HOW TO PLANT



RESEARCH
Research begins at Purdue University in 1968. Over 400 specimens collected and planted in clone banks. All but the eight fastest growing and straightest trees are culled. Those eight are awarded patents in 1979 and 1980 based on superior growth and form.

 

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DEVELOPMENT
Beginning in the mid-80s, two of the best of the eight varieties, namely Purdue No. One and Tippecanoe No. One, are propagated and sold. In the mid-90s, six new cultivars with superior form and growth rate are introduced.

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CHARACTERISTICS
As the trees mature, their form improves to one on a scale of one to five, where one represents a perfectly straight central stem and five is basically a bush. Grafts (clones) of these varieties have the potential of growing over an inch in diameter each year. While it’s not possible to reach that potential except rarely, it is feasible to attain an average growth rate of up to .6-inch diameter growth per year. This growth rate will yield a saleable log in 25 to 30 years.

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PROJECTED VALUE
The most ever paid for a single black walnut log was $90,000. Current prices paid for prime veneer-grade black walnut range from about $3 a board foot to over $15 a board foot. As a result in the decline in the supply of high-quality veneer trees, there are fewer companies today able to offer a line of black walnut products. This has resulted short-term instability in the market. Only when significant numbers of these trees are harvested will price stability be restored. We project that the prices for these trees will be approximately as follows: 25 years: $ 2,000 30 years: $ 5,000 35 years: $10,000. It’s worth noting that these trees do not have to be harvested at a particular time. If the price in one year is not favorable, harvesting can be postponed until it is. In the meantime the trees will continue to grow in size, which makes them even more valuable.

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HOW IT ALL BEGAN
From the very first settlements in the New World, the tallest, fattest and straightest trees were always the first to be cut down. Unfortunately, none were replanted. Instead, the slower-growing, crooked trees were left behind in the forests to reproduce. We’ve been doing that for the past 300 years. The effect on the eastern black walnut gene pool has been disastrous. Only in the last 50 years has any thought been given to reversing that process and replanting with superior varieties.

However, varieties with proven superiority in growth rate and form did not exist until researchers at Purdue University discovered and isolated them in clone banks in the 1970s. They started with over 400 specimens from trees whose appearance met their selection criteria. These specimens were grafted onto black walnut rootstock, planted in clone banks and carefully monitored for over a decade.
In 1979 and 1980 Purdue University was awarded eight patents for cultivars that were demonstrably superior in growth rate and form compared to other varieties of black walnut trees.

During the time the trees were studied at the clone bank at Martell Forest in West Lafayette, Indiana, Purdue No. One and Tippecanoe No. One averaged over one-half inch growth in diameter per year, and that’s without a consistent, progressive weed-control and fertilization program that we know today will enable the trees to do even better. Nonetheless, by the 20th year they were already 75 percent larger in volume than run-of-the-nursery seedlings in a control planting nearby.

In the mid-90s six new cultivars were introduced. These were composed of three cultivars that were second and third generation genetically selected enhancements of three of the original patented cultivars and three that, though not patented, were developed by the same professor who developed the patented varieties. The six new cultivars are equal to the Purdue No. One cultivar in form and have been observed in one plantation to actually grow faster than Purdue No. One.

Superior Form and Rate of Growth Superior form is necessary to produce high-quality prime veneer-grade wood. This is the most valuable grade of wood and is today very scarce. However, trees that grow slowly and do not reach harvestable size for upwards of 50 years are not very interesting to most growers. That’s why rate of growth is equally important.

Our genetically improved black walnut trees have the potential of growing over an inch in diameter per year. That’s the maximum potential. In the real world, maximum potential is only rarely realized. However, if properly cared for and with a little help from Mother Nature, we believe these trees can average at least .6 inch diameter growth per year. In 35 years we estimate that, if properly cared for, these remarkable trees should be 20 inches in diameter and up to 80 feet in height.

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HOW MUCH ARE THE TREES WORTH?
The intrinsic value of black walnut has been thoroughly tested by time. For centuries it’s been one of the most desirable woods in the world. Its enduring appeal rests solidly on its innate beauty, richness and purity.
While there’s no way to accurately predict prices 25 to 35 years down the road when the trees are to be harvested, it is helpful to understand the market forces that create those prices. However, prices paid for black walnut (and other hardwoods) are not easy to come by. Deals made between the seller and buyer are private and seldom publicized. When the prices are made public, their accuracy is sometimes suspect. Buyers are loathe to reveal how much they pay because doing so tends to increase the expectations of future sellers.

Nonetheless, anecdotal evidence collected from various industry sources allows us to feel confident of our findings.
The Past Prices for veneer-grade black walnut reached their peak in the late 1980s. Since then, the supply of such logs has become so scarce that demand has fallen substantially.

When the supply of a particular raw material or component falls below what marketers call, “critical mass,” manufacturers switch to alternative materials. “Critical mass” is defined as the amount of a raw material needed to maintain a product line offering. Thus, when the supply of black walnut became problematic in the early 1990s, veneer mills and paneling and furniture manufacturers began substituting black walnut with other woods. At the same time they naturally altered their marketing and promotion to support products made of these other woods, stating that black walnut was no longer fashionable.
The fact is that, irrespective of price and availability, black walnut has an enduring spot as one of the four most sought-after woods in the world, the others being mahogany, teak and cherry.

  • The most ever paid for a single black walnut log was $90,000. That was in the mid-1980s. There are many other examples of smaller logs going for between $20,000 and $40,000.
  • Mahogany and teak are currently subject to an informal moratorium on harvesting trees in tropical rain forests.

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THE PRESENT
Because of a drastic drop in the supply of veneer-grade black walnut, the prices currently paid by mills are erratic. The behavior of market prices for black walnut no longer fit neatly on the demand/supply curve; rather, they largely resemble the market prices for rare art objects; i.e., they can and do vary widely depending on how badly a particular buyer wants the item.

The prices paid over the last five years reflect this squeeze on supply. Prices range from about $3 a board foot on up to over $15 a board foot. The only thing that can and will change the situation is an abundant supply of black walnut.
Veneer buyers who have looked at these genetically improved trees estimate that a tree with a DBH (Diameter Breast Height) of about 20 inches should produce veneer-grade wood worth about $10.00 a board foot at today’s prices. Once the supply increases and more companies incorporate black walnut into their product lines, the prices should again begin to rise at the historical rate of four to five percent above inflation.
The Future We estimate that in 25 years these trees, assuming they’re been properly cared for and planted on good sites, should be worth about $2,000 each. In 30 years they should be worth about $5,000 each. In 35 years they should be worth almost $10,000 each.

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ASSUMPTIONS
Growth Rate:
It’s been proven that these genetically improved cultivars have the potential of growing in excess of one inch in diameter per year. Since it’s impossible to achieve maximum potential growth consistently, we estimate that a properly cared for tree on a good site will average .6 inch caliper growth per year for the first 25 years, .5 inch for the next five years and .4 inch for the last five years.

Survival Rate:
Even though the trees are healthy and viable, we recommend being conservative on estimating survival rates. We therefore estimate that one acre should yield 110 trees in 25 years; 100 trees in 30 years, and 90 trees in 35 years.

Current Value:
The current price range for veneer-grade black walnut is from $3 per board foot to about $15 per board foot. There are occasional sales at higher rates but they are too few to be factored into our estimates of current value.

Future Value:
The Governor’s Conference on Indiana Agriculture states that prices for veneer-grade black walnut traditionally increase between four and five percent per year. For the purposes of our calculations we use 4% per year.

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HOW TO GET THE BEST PRICE
The best way to get high prices is to attract multiple buyers who will then bid against one another for the trees. This requires enough trees to make it feasible for companies to maintain a black walnut product line for an extended period of time. We estimate that to attract multiple bidders you should have at least 100,000 board feet of veneer-grade wood.
It may even be feasible to get companies to pay a deposit on trees prior to harvesting, if they know the pedigree and are confident the trees have been cared for properly. You should also consider harvesting your plantation in phases, harvesting every other tree one year, then every tree in alternating rows several years later. This “releases” the remaining trees so that they can continue growing at the optimal rate.

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IS FAST-GROWING WOOD LESS DESIREABLE?
There is a prevalent belief among tree farmers and foresters that the faster a tree grows, the softer and less desirable is the wood. In the case of black walnut, this belief was proved false by G. H. Englerth, a scientist at the Forest Products Laboratory in Madison, Wisconsin over 20 years ago.
Professor Englerth conducted toughness and machining tests on wood from slow, moderate and fast-growing black walnut trees. Toughness is the ability of the wood to resist shock, a crucial characteristic in wood used in chairs, tables, desks, sporting goods and musical instruments.
Toughness Toughness is a function of the wood’s specific gravity, compression failure, the presence of tension wood or decay, knots and grain deviation. The higher the specific gravity, the tougher the wood and the greater its ability to withstand shock. The specific gravity of the fast-growth wood was found to be 21 percent higher than the slow-growth wood and ten percent higher than moderate growth wood. The consensus is that this is a result of lignin being developed and deposited more rapidly in the fast-growing trees.
Machining Planing is the most important machining operation because a smooth surface is essential for subsequent sanding and finishing. Fuzzy grain and chipped grain are the two most frequently found machining defects.
In these tests, the depth of the cut was 1/8 inch. No defects of any type occurred in the wood from fast-growth trees.
Excerpted from Machining and Other Properties of Fast- versus Slow-grown Trees by G.H. Englerth, Forest Products Laboratory, Madison, Wisconsin. Italics added for emphasis.

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MAXIMIZING THE RETURN ON PLANTATION INVESTMENT

The best way to maximize the return on investing in a plantation of genetically superior black walnut trees is to minimize the risks to those trees by optimizing their growth and health.

That basically consists of making sure the trees are receiving the right amounts of the right inputs. That means water, nitrogen, phosphorus, potassium and certain trace elements.

With all the proper inputs in place and a little help from nature, the trees will not only thrive, they will grow at an astonishing rate. We believe these trees have the potential of averaging up to .6-inch in diameter growth per year. We believe this growth rate will continue until the tree reaches about 15 to 18 inches in diameter, at which point the potential growth rate will gradually begin to decline. The average vertical growth potential has been shown to be at least three feet per year up to about 60 to 80 feet at which point the potential growth rate will gradually egin to decline. In the first three or four years it’s not unusual for the trees to average five feet a year or more in vertical growth.
Greenwood Nursery provides instructions on virtually every aspect of optimizing the care of these trees, from soil testing and analysis to planting techniques, weed control and pruning. While none of these is difficult to master, it is important that growers understand what is needed to optimize the growth and health of their trees.

How Much Time Will It Take On the average, beyond planting the trees, figure about five to 15 minutes per tree per year, though not all at the same time. The major tasks are applying lime, fertilizer and herbicide (normally two to three applications per year) and pruning (normally once every two to three years for each tree).

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WHERE TO PLANT
The importance of selecting and preparing the site for planting your black walnut trees cannot be over-emphasized. While it’s not difficult to understand what conditions will enable your trees to do well, some growers pay too little attention to these points in the enthusiasm of getting the trees planted.
The trees will do well in hardiness zones 4 through 8, though the best are zones 5 through 7. The trees are highly adaptable and hundreds of acres have been planted successfully from Minnesota and New York to Louisiana and Georgia. The Best Soil Select a site that has a loose, well-drained, loamy soil at least two to three feet deep and with a good amount of organic matter (humus). Not only will loose, well-aerated soils enable the trees’ roots to absorb more moisture, they will also allow for more rapid root growth.

By “well-drained,” we actually mean two things. First, there should be no standing water, except possibly for a small amount of flooding in the spring. Second, the soil should percolate well. Good percolation means the water will drain readily through the soil but not so readily that the trees’ roots do not have enough time to absorb the moisture.

Obviously then, the soil should also have good moisture holding properties (not like sand, for example). A hillside may satisfy the first requirement, but if the soil there is compacted or composed primarily of clay, it will not percolate well.
You should avoid soils with a thick layer of blue or heavy brown clay and frangipans.
A site with moderate amounts of clay can often be treated with a solution that breaks loose the bound water found in such soils. If you have this kind of soil, you might want to give us a call to discuss possible solutions.
There should be nothing beneath this layer of top soil to impede drainage. Obviously, if water percolates well though the topsoil, the subsoil is most likely okay.
Most soils are compacted to a degree. In preparation for planting we strongly recommend using a subsoil implement to loosen the soil. Doing so will also make it easier to dig the holes when that time comes.

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HOW TO PLANT
When you pay your deposit, we will send you Site Prep and Planting Instructions. Follow the instructions and you should have a successful plantation.
Once you’ve chosen a site you should have a soil test done to determine the soil pH and fertility. Black walnut requires a soil pH of 6.5 to 7.0. KAg Laboratories of Oshkosh, Wisconsin, is more knowledgeable about the needs of black walnut than any other lab we are aware of. Click here to visit their website.

Fertilizer Insurance Regardless of what fertilizers and micro-nutrients the soil lab recommends, we strongly urge you to drop a time-release fertilizer pack into the hole alongside the roots of the tree. That’s because even with the right fertilizer mix and good weed control, not all the fertilizer will reach the roots.
Water So far as the amount of water the trees need in the first year, figure a half-gallon a week during slight droughts and up to two gallons once a week during extreme droughts. Make sure to thoroughly saturate the soil where the roots are.
Of course, with plenty of rainfall, there’s no need to water.

Even still, some growers want the additional reassurance that irrigation provides, so they install a drip irrigation system. In areas where there is normally enough rainfall, an irrigation system is usually not necessary; however, be prepared to supply water the first couple years if nature doesn’t.
By the time the tap root has grown down into the water table, you shouldn’t have to bother watering at all, except possibly during a severe drought.
Mulching We also recommend mulching around the trees. Mulching suppresses the growth of weeds and preserves moisture in the soil. Do not choose a mulch that’s still fresh; let it “age” awhile outside. Also, avoid mulches that are contaminated as some are. An easier solution is to use weed mats, which are available from us at a small price.

Weed Control If there are weeds growing in profusion around your trees, guess where the water and fertilizers go. To the weeds. You’ll have the best-looking weeds in your area. And the worst-looking trees.
There are several ways to get rid of weeds. Prior to planting the trees, you can plow the weeds under. This may take several passes but has two distinct advantages: One, you’ll use less herbicide. Two, it further loosens and aerates the soil. If that’s impractical, you should apply a mixture of Princep (a pre-emergent) and Round-Up three to four weeks prior to planting. However, don’t let weeds treated with these herbicides come in contact with the black walnut trees’ leaves. Be sure to follow label directions completely. If you’re not absolutely sure about how to do this, get help from the manufacturer or someone who specializes in herbicides.
Mycorrhizal You should plan on applying Mycorrhizal when you plant the trees. These symbiotic micro-organisms form a mutually beneficial relationship with the trees’ roots, thereby enabling them to absorb more water and nutrients faster. Mycorrhizal comes in two forms, Root Saver, a dry granular powder for the potted grafts and Root