Lignin for

Better unextracted carbohydrate. The residue may be applied directly to the soil without further treatment, if care is taken to avoid contact with growing Crops plants, for the acid in the lignin causes burns. After the residue is rained on, w^ashed, or treated with lime to neu- Elwin E. Harris tralize the acid, it loses its tendency to cause burns. Lignin left as a residue from the Scholler process of alcohol production Lignin is the part of the wood that in Germany has been reported to be a remains after its carbohydrates and ex- suitable soil conditioner. The first ex- tractives have been removed by hydrol- periments in the United States on such ysis or by the action of molds and use of lignin left as a residue from an bacteria. In that respect it is like the acid hydrolysis W(TC started in 1936, material from which soil humus is when research w^orkí^rs at the Forest formed. For the formation of soil Products Laboratory treated clay gar- humus, plant material (such as strawy den soil with lignin at the rate of 5 tons leaves, and sawdust) must be acted on to the acre. At the same time they com- by soil bacteria, which use the carbo- pared the treated soil, some of which hydrates and convert the residue to had had inorganic fertihzer, with un- humus. In their utilization of the carbo- treated soil, some of which also had hydrates, bacteria require nitrogen; received the fertilizer. Tomato plants unless an abundance of nitrogen is grown in the soil receiving both lignin present, plants growing in the soil may and fertilizer were more vigorous and sufter from nitrogen deficiency. Lignin bore more fruit. The plot receiving does not have so high a nitrogen de- fertilizer and no lignin was next in mand as do plant materials that con- yield. Plants in the plot receiving lignin tain carbohydrates. and no fertilizer were healthy and bore Lignin is slow'ly changed to humic good fruit, but were smalh^r than those substances when mixed wdth soil. Even fertilized. Plants receiving no lignin before it is converted to humus, how- and no fertilizer suffered during dry ever, it has many of the properties of weather and gave poor yields. The soil humus, such as ability to react with in plots that reciuved lignin w^as easier minerals in the soil, to control the size to cultivate and did not become hard of aggregates in clay, and to aid in con- when it dried after a rain. trolling the alkalinity of soil. Wood-hydrolysis lignin, when used Lignin in solid form remains as an as a mulch between rows of tomatoes, insoluble residue when sugar is made kept the soil moist and was easily from w^ood. When wood is treated with w^orkcd into the soil. dilute acid under pressure, as in the Stuart Dunn, of the New Hamp- Madison wood-sugar process, the cel- shire Agricultural Experiment Station, lulose is converted into soluble sugar tested the use of lignin from wood sac- and the lignin is left as a dark-brown charification supplied by the Forest residue. The residue contains about 50 Products Laboratory for potato pro- percent moisture, about 0.5 percent duction. Plants were grown in l4-quart sulfuric acid, and small percentages of pails in Newmarket sandy loam with 883 884 1950-1951 YEARBOOK OF AGRICULTURE thin layers of lignin between layers of ratory in both greenhouse and ñúá soil. The lignin was equivalent to 5 tons w^ork. He reported a distinct value to an acre. The plants were compared greenhouse operators in its use. Lignin with controls in the same loam without from wood-sugar production and with- lignin and wâth plants of another group out any treatment lowered the alkalin- in loam containing lignin and sulfur. ity of greenhouse soils and, at the same Commercial fertilizer was added to all time, was a good soil conditioner. pails. The average yield of the potatoes Chrysanthemums grown in soil to per pail in each group was: Lignin w^hich 10 percent of lignin had been alone, 451.2 grams; lignin plus sulfur, added produced longer stems and bore 411.4 grams; and the control with larger blooms than the control. From fertilizer but no lignin or sulfur, 319.2 actual weights of every stem cut, the grams. Analysis of the tubers gave the flowers from this plot showed approxi- following starch content : Lignin alone, mately a 30-percent gain in weight. 19.68 percent; lignin plus sulfur, 11.77 Lignin that w-as applied in 1948 and percent; and control, 10.24 percent. 1949 to alkaline spots in irrigated fuîlds VV. B. Bollen, of the Oregon Agricul- in Montana improved soil conditions. tural Experiment Station, has reported Harry L. Hamilton, of the Forest on wood-saccharification lignin used Products Laboratory, and Emil Truog, in much the same manner as horticul- of the University of Wisconsin Agri- tural peat moss. He found that lignin cultural Experiment Station, in 1948 is preferable to leaves, straw, and saw- and 1949, tested the use of lignin in dust as a mulch and soil conditioner in both field and greenhouse. An im- gardening; and that it forms smooth provement was noticeable in the mulches, incorporates readily with the greater ease of cultivating and in a soil, and eventually contributes to more open structure of the soil. Phys- humus formation. In this experiment, ical properties of the soil were im- lignin'was used as a mulch for starting proved by the addition of lignin. The plants from seeds in flats and as a light improvement continued through sev- mulch over seeding. By holding mois- eral crops with respect to soil hardness, ture, the lignin enhanced germination. water-holding capacity, porosity, and By maintaining a loose, open soil, it rate of water flow through the soil. permitted sprouts to break through the Lignin from wood saccharification is soil readily. The use of lignin in potting not yet commercially available, but if soil or as a bottom layer in flats and industries find it practical to put up pots resulted in vigorous plant develop- plants to convert w^ood waste into mo- ment. As a heavy mulch around rasp- lasses for feeding livestock, large quan- berry and other cane-fruit plants, and tities of lignin may become available, around blueberry plants in depths of 4 because each ton of dry w^ood waste to 6 inches, it gave smooth, compact yields about 600 pounds of lignin. A mulches that held moisture and pro- plant producing 50 tons of molasses a vided conditions approximating the day would produce 15 tons of dry lig- natural habitat of the plants. nin, or about 4,500 tons a year. At a Lignin supplied by the Forest Prod- rate of 5 tons of lignin to the acre, this ucts Laboratory was compared in 1949 would treat 900 acres of land a year. and 1950 to other materials for subsoil If all the sawmill wood waste collected drainage in golf greens at the Missoula in the United States (60 million tons) Country Club in Montana. A report of a year were converted into sugar and the condition of the greens after a year lignin, the lignin, applied at the rate of was favorable to lignin. 5 tons an acre, w^ould be sufficient for F. M. Harrington, of the Montana the total acreage (about 6,000 square State College and Agricultural Experi- miles) in one of the smaller States. ment Station in Bozeman, used lignin As the lignin comes from the process, supplied by the Forest Products Labo- it is a moist residue containing about. LIGNIN FOR BETTER CROPS 885 50 percent solids and 50 percent water. liirnin products at the Forest Products Where it is to be transported for short Laboratory, Madison, Wis. He re- distances, it need not be dried. ceived his bachelor's degree from Hamline University, and has advanced. ELWIN E. HARRIS is in charge of the degrees from the University of Minne- work on wood saccharification and sota.

THERE IS GOLD in sea water. A generation ago much was heard about various schemes for recovering it in commercial quantity. An eminent German chemist, Fritz Haber, analyzc.-d numerous natural waters from all over the world and found that nearly all of them really did contain measurable traces of the pre- cious metal. I'he water of San Francisco Bay ranked high in gold content among HabcT's samples. It contained 0.01 milligram per cubic meter of water—or 92 pounds of gold per cubic mile of Bay water, worth $47,000 at a gold price of $35 a troy ounce. No factory for extracting it has hc.cn built. If there had been, the operators might soon have been diverted from their orighial purpose by the lure of the other valuable chimiicals in that same cubic mile of sea water: 230 tons of iodine, worth 700.000 dollars: 330,000 tons of bromine, worth 140 million dollars; 4 million tons of magnesium, worth 1.5 billion dollars; 75 million tons of chlorine, worth 5.7 billion dollars; and 50 million tons of sodium, w^orth 18.5 billion dollars. Those facts are not unrelated to agricultural research. Any farm commodity you can name is a veritable mine of rare and expensive chemical compounds. Anyone armed with a reasonably complete analysis of alfalfa, say, and a chc^m- ical price list, can easily show that a ton of alfalfa should be worth at least $2,000—^just as a cubic mile of sea water evidently should be worth at least 25 billion dollars. But what's wrong with such a conclusion? Two things: First, the cost of extraction of a pure substance from a natural source may be so high as to price it out of the market; second, the market may be so thin or so inelastic that even a littler extra production will break the price. If someone were so ill-advised as to produce 50 million tons of sodiun\ in a single year he would find himself embarrassed by a thousand-year stockpile, and unable to find takers for most of it at any price. Nevertheless, sea water is an important commercial source of salt, bromine, and magnesium. The value of the salt produced annually from San Francisco Bay water far exceeds the value of all the gold in the bay. The story of bromine is instructive. Chemists had found long ago that sea water contains a little of it. Many years later the development of antiknock gasoline multiplied the demand for bromine enormously. The c^hemists worked out a method for recovering it from sea water more cheaply than it could be produced from other known sources. Engineers developed a practical large-scale process. Businessmen put up the money. And a new industry came into existen(T. A similar thing happt-ns constantly in agricultural research. Scientists discover unsuspected values in farm products, a market opportunity is glimpsed by some- one who can command enough capital to go after it, and the engineers and technologists bring another new industry into being. It is no fairy story—it's the way our industrial civilization operates.—W. B. Van Arsdel, Western Regional Research Laboratory.