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1 JUNE, Goose. Experiments will be conducted to determine the best dropping procedure--probably at about 800 feet at 130 m.p.h. We seem to have strayed somewhat from the objective of this panel -"How to achieve a co-ordinated fire prevention and control program in a managed forest unit." The solution is simple enough-there is no better incentive than enlightened self interest-just create the proper atmosphere which will allow free expression of ideas, and co-ordination is bound to follow co-operation. Operators in each Working Circle should set up their own fire control group and hold regular monthly meetings which the local Ranger and district fire prevention officer would also attend. They would soon evolve a system of standardization of equipment, material and methods. They will all benefit from each other's experiences. But first they have to trust the other guy! LITERATURE CITED (from page 135) 16. PILLOW, M. G., SCHAFER, E. R. and J. C. PEW Occurrence of compression wood in black spruce and its eflect on groundwood pulp. U.S. For. Prod. Lab. Rept. No. R pp. 17. Province of British Columbia, Dept. of Lands and Forests Report of the Forest Service, year ended Dec. 31, pp. 18. RIETZ, R. C Kiln drying of Engelnlann spruce. U.S. For. Prod. Lab. Rept. No pp. 19. SCHAFER, E. R Engelmann spruce for pulp and paper products. U.S. For. Prod. Lab. Rept. No pp. 20. SPURR, S. H. and W-Y. HSUING Growth rate and specific gravity in conifers. Jour. For. 52(3): VINCENT, REX Dissolving pulp forecast Pulp and Paper 33 (8) : , 104, 106. World Review Number. 22. WELLWOOD, R. W. ef a! Unpopular species and their increased use. For. Chron. 33 (1): WOOD, L. W. and J. 0. BLEW Engelmann spruce and its preservative treatment for ties and mine timbers. U.S. For. Prod. Lab. Rept. No pp.

2 PRESENT USES OF SPRUCE A panel discussion on this subject was presented at the 1959 Annual Meeting of the Canadian Institute of Forestry at Prince George, B.C. The chairman was Mr. C. F. McBride, Forest Products Laboratory, Vancouver, B.C. Papers were presented by Dr. R. W. Wellwood and Mr. K. G. Fensom. Mr. Fensom's paper, entitled The Characteristics and Significance of Spruce, was summarized on page 84 of the March 1960 issue of The Forestry Chronicle. It is available as V-1026 in the regular multilith series of the Vancouver Laboratory of the Forest Products Laboratories of Canada, and can be obtained on request from the Vancouver Laboratory, 6620 N. W. Marine Drive, Vancouver, B.C. THE UTILIZATION OF SPRUCE IN CANADA By R. W. WELLWOOD It is entirely fitting that Canadian foresters should spend a full annual meeting discussing spruce. The spruces form the most abundant timber species in all provinces of Canada excepting Newfoundland proper, where the volume of balsam fir somewhat exceeds that of spruce. In B,ritish Columbia, although the cut of Douglas fir still exceeds that of spruce (17), the volume of standing spruce timber far exceeds that of Douglas fir and of other species (4). According to Forestry Branch data (4), spruce makes up about 42 percent of Canada's merchantable softwood stands and 35 percent of all merchantable timber. We can therefore state that spruce makes up about one-third of Canada's timber resource. Spruce stands, either pure or mixed, extend from the Atlantic to the Pacific, and occur in all provinces and the Territories (2, 3). In discussing spruce we are considering several species of one genus, that extend through many parts of the temperate zone of the northern hemisphere. Some of them are almost identical in properties and appearance (2). White spruce, including the western white variety, is Canada's most important timber tree. It probably has as wide a range as any Canadian tree since it extends across Canada, from Newfoundland and Labrador through British Columbia and Alaska. Black spruce has a similar but more restricted range and is normally a smaller tree. Red spruce has a range essentially limited to the Maritime Provinces and southern Quebec. Engelmann spruce, on the other hand, is native to western North America, extending from New Mexico in the south to central British Columbia as the northern limit of the species. Sitka spruce is restricted to coastal British Columbia, and is by far the the largest of all spruces (3). Professor, Faculty of Forestry, University of British Columbia, Vancouver 8, B.C. 126

3 JUNE, Just as the spruce resource is impressive, so also is the annual cut. In 1956, the last year for which data are published (4), spruce and balsam fir together accounted for about 2.7 billion ft. b.m. of the lumber cut in Canada, or about 35 percent. Douglas fir accounted for about 27 percent of the total cut, but its value probably still exceeded that of the spruce and balsam. Currently, Canada's pulp and paper mills use in excess of 10 million cords of spruce and balsam (6). These species, which are not separated in the statistics, accounted for about 73 percent of the pulpwood cut in Timber cut for other purposes is relatively minor in amount and is unclassified as to species. PRODUCTS MANUFACTURED The major items manufactured from spruce are obviously pulp and paper, and a wide variety of lumber products. A relatively small volume of round timbers are made from spruce, but plywood is a product of growing importance. The range of items made from spruce indicates its versatility, so that any discussion of spruce utilization should consider some of the unique properties of these species. Pulp and Paper Spruces are the favored species of the pulp and paper industry, and are the standard by which other woods are judged in all parts of Canada with the possible exception of the West Coast. Although hardwoods were first used by the Canadian pulp industry, spruces have long been the principal woods used in the three major pulping processes. They are particularly desired by the sulphite and groundwood mills where they command a premium price, whereas the sulphate mills frequently use wood from less costly species. The wood of the white spruce group is light in weight, light in color, and relatively free from resin. Density differences between springwood and summerwood are moderate. The fibres have a good length and an excellent length-diameter ratio, resulting in a pulp with well balanced strength properties, good color and a high brightness. In mechanical pulping the power requirements are lower than for many other species. These factors more than offset the moderately low density of the wood. Sitka spruce has the longest fibre of any important commercial North American pulping wood. The pulp has a pinkish cast but this can be eliminated readily by bleaching or brightening. Black spruce has been described as "The backbone of the Canadian pulp industry." Of the spruces it has the greatest density and gives the highest pulp yields. On the other hand the trees are frequently small, and too limby to be useful for saw timber. The knots resulting from these same limbs are usually small and black in color, resulting in black specks in the pulp. These are not a major defect in pulp quality, however. According to the United States Forest Service (19), Engelmann spruce has a lower density, on the average, than its eastern counterparts, but the larger and straighter logs give a greater volume of solid wood per cord. Canadian data (10) do not substantiate the lower density figures. In any event differences are minor and may be obscured by sampling variations. Rate of growth of individual trees of various species affects wood density (20), as does age of the wood at time of sampling, hence the problem of obtaining average density figures for a species is a complex procedure.

4 128 FORESTRY CHRONICLE Compression wood occurs in all softwood species and affects wood density as well as other properties. This anatomical characteristic is fairly prevalent in spruce. It affects pulp properties adversely, and is therefore considered a defect (16). It is also considered a defect in other wood products. Eastern Canadian mills have long used spruces as their major source of material, first for groundwood and sulphite pulps, and later for sulphate pulps. Sitka spruce was the principal species used by West Coast mills until about 15 years ago, but its leading position has been taken by western hemlock. This is due partly to the limited quantity of Sitka spruce and partly to the excellent qualities of western hemlock. The one operating non-coastal western mill, at Hinton, Alberta, is the only Canadian mill using western white spruce. (It also uses black spruce, alpine fir and lodgepole pine.) However the movement of spruce pulpwood from Alberta, Saskatchewan and particularly the western states, to Lake States pulp mills, has been growing in volume since about 1939 (19). One of the great untapped pulp potentials of North America is the spruce region of northern British Columbia. Sulphite pulps made from spruce, true firs, and hemlock are used for making newsprint, bond, book, writing, wrapping and tissue papers, a wide variety of special papers and boards, and rayon and other cellulose derivatives. Spruce sulphate pulps are prized for the manufacture of the highest quality specialty papers, wrapping and bag papers, and for blending with other pulps to impart strength in a wide variety of paper and board products. Only in resistance to tearing is the strength of spruce sulphate pulps exceeded by those from the coarser-fibred southern pines and Douglas 6r (19). High quality groundwood pulp can, of course, be made from spruce. Most of the groundwood produced is used in newsprint, which is generally made in the same mill. A large tonnage is also used in the manufacture of container board, in the cheaper classes of book and magazine papers, wrapping papers, toilet papers, and such products where low price is more important than high quality (2). Canadian newsprint is recognized as excellent by world standards, due in a large part to the spruce component. This is fortunate for Canadian mills because, in the United States market at least, they are selling a quality product made from high cost wood; a product frequently shipped long distances, in competition with newsprint shipped lesser distances but made from inferior pulping species. In overseas markets they may be competing with products of equal quality, usually from northern Europe. Spruce has already been described as a superior wood for the sulphite process. In addition, it has a high alpha cellulose content which is desirable in the highly purified pulps that are later dissolved and transformed into cellulose products. Much of the world's supply of dissolving pulps for use in the rayon and other cellulose industries is made from spruce. A serious competitor in Canada is western hemlock used in the B.C. coast mills, but Canadian spruce remains a major source for these high value pulps. Some six pulp mills are currently producing this type of pulp, and one other is inoperative. At least four of.these use spruce and fir almost exclusively. Although this is an important segment of the pulp industry in Canada, and produced about six percent of the world's supply in 1958, it is one that does not have as bright

5 an outlook as other major parts of the industry. The reasons are complex, but are associated with the superiority of sulphate-dissolving pulp, which is not manufactured in Canada, for the important tire cord market. This market itself is highly competitive with nylon. Other factors include competition in several other fields from the increasing number of synthetic fibres, and increased domestic pulp production in Japan and other major producers of cellulose products (21). Round Timbers, Railway Ties Spruces are used only to a minor extent as round timbers or as railway ties. The species are somewhat difficult to treat with preservatives, being classed as resistant to penetration by liquids (1,23). Such treatments have been done on a limited but reasonably successful commercial basis, however, for many years, particularly with creosote and to a lesser degree with water-soluble preservatives. Although spruce trees often have a form suitable for use as round timbers they are not preferred species. Spruces are not listed as pole species under either the American or the Canadian Standards Association, although there seems to be no logical reason for their omission. Their natural durability is low and other species, such as the pines for example, are easier to treat. The stumpage value of poles makes them an attractive item in forest management. Spruces are used to a limited extent as piling species, and are listed by the Canadian Standards Association (7). Some untreated spruce railway ties are undoubtedly used in the major railroads. Creosoted spruce ties have given good performance (23) but have not been widely used in Canada, denser woods being preferable for this use. Spruce, particularly black spruce (2), is used locally in varied areas for mine timbers, but the volume is not significant in the overall picture. Lumber Spruce wood is light in weight, but the high strength/weight ratio makes it suitable for many uses, including such specialties as aircraft parts and helicopter blades. Although it is lighter and somewhat weaker than several other commonly used construction woods, its strength is adequate for most purposes (8). For example, in house construction 2- by 4-inch studs at 16-inch spacing will meet all requirements (13). Likewise, the strength is adequate to permit its use in ordinary one-inch lumber for wall and roof sheathing, subflooring and similar applications where lightness in weight and ease of nailing and working are advantageous. House construction is, of course, one of the major uses of spruce. Although it might be desirable to use clear, defect-free wood for all structural purposes this is neither physically nor economically possible. In tests to failure made at the Forests Products Laboratories of Canada (F.P.L.C.) on 1,215 seasoned white spruce joists of sizes ranging from 2 by 4 inches to 3 by 9 inches, the presence of knots accounted for 76 percent of the failures (2). Specifications for grading rules place limits upon the size, type and location of knots, being less rigid for the appearance grades than for the structural grades. Select grades, in either the appearance or stress classification, probably would not exceed about 5 percent of the lumber sawn at

6 130 FORESTRY CHRONICLE a mill cutting spruce from an average stand, with the exception of mills cutting Sitka spruce. There are no particular problems in kiln drying spruce. Drying schedules are available for various thicknesses and grades, from publications of the Forest Products Laboratories of both Canada and the United States (15, 18). Face checking and end splits are apt to develop if air-drying is too rapid (2). These can be controlled by manipulating pile height and width, pile spacing, ventilation, sticker placement and other factors. Numerous dry kilns operate, partly to reduce the shipping weight of the lumber because of the distance from market, and partly to meet the demand for properly dried lumber. Spruce does not machine as well as white pine but is better than Douglas fir. It does, however, work easily and finishes smoothly using tools with sharp cutting edges. The machining defects most commonly developed in spruce, according to tests at the United States Forest Products Laboratory (U.S.F.P.L.), are fuzzy and raised grain (1). These defects are minimized when the lumber is machined at a moisture content of about 12 percent. In general spruce can be machined satisfactorily to very well. Spruce has many properties that make it desirable for the house builder (13), including good nailholding properties, freedom from splitting when nailed, freedom from warping, lightness in weight and ease in working. Its shrinkage is greater than that of white pine and the cedars, and about the same as that of Douglas fir. Although spruce has many applications in house building, it cannot always be used interchangeably with Douglas fir or western hemlock due to its lower strength. In the United Kingdom market Canadian spruce is used interchangeably with the long-known and well-accepted Baltic species (1 1 ). In addition to the uses noted for spruce in house construction, namely studding, sheathing and subflooring, it is widely used in joists and rafters. Here the lower strength of spruce must be taken into account. In addition, spruces are favored woods for scaffolding planks, concrete forms, ladder rails, oars and paddles, and similar uses, because of their lighter weight and resilience (2). A minor use of spruce is lath. For applications where appearance is a factor spruce has several noteworthy advantages. The wood has high brightness or natural lustre and a uniformly white color. To this can be added a fairly uniform distribution of small tight knots that provide an attractive pattern for interior wall paneling. A number of operators have capitalized on the attractive appearance of spruce and have developed specialty panel grades. Natural finishing of spruce is enhanced owing to its low resin content, and it takes colorless finishes well (13). Spruce has good painting characteristics and is suitable for use as exterior trim and siding. In both of these uses it would be inferior to white pine but superior to Douglas fir and larch. Spruce, with either a natural finish or a high-class paint finish, is eminently suited for use in shelving, where the requirements include stiffness, good finishing qualities, and freedom from pitch and from warp (13). Roof decking is a popular current use. It is used for flooring and for ship decking although inferior to the denser woods for this purpose. It is also used for other interior finish and woodwork, ironing boards and for general-purpose furniture and cabinets. Because spruce is almost tasteless and odorless when seasoned,

7 JUNE, it has long been a favorite for butter boxes. Other types of containers, and slack cooperage, together utilize a large volume of spruce. It is also used for wood flour. A unique use for spruce is in the sounding boards of pianos and the sound boxes of violins. The high resonant qualities of slow-growing, straightgrained, knot-free spruce make suitable wood a valuable product, although the market is restricted. Veneer and Plywood A relatively new use for spruce is in the veneer and plywood industry. TO the writer's knowledge very little spruce is currently being sliced, but there is a potential market for both clear and knotty veneer produced from cants or flitches. During the Second World War a substantial quantity of Sitka spruce veneer was quarter sliced at a Coast plywood plant, for the wooden aircraft program. Spruce logs (excluding Sitka spruce) as a rule produce very little clear wood, but a small percentage of clear cants could be obtained and a much larger percentage of high-quality knotty cants. It must be remembered that one board foot of cant will produce enough veneer to cover 6 to 8 square feet of plywood panel. The production of spruce plywood is an established part of the industry in northern Europe, where spruce is used along with pine (ll), and is becoming so in British Columbia. A few mills on the Coast have made small quantities of rotary-cut Sitka spruce plywood for several years. An increasing volume is being used currently to make sheathing plywood, in mixture with Douglas fir veneers. Only within the last few years has hot-pressed plywood been manufactured from Engelmann and white spruce. At present two plywood plants in the Interior of B.C. manufacture spruce plywood as a regular item of production. In one plant spruce forms about 30 percent of their production. Both are optimistic about the future of spruce plywood, which has many of the advantages of spruce lumber plus the general advantages that plywood has over lumber. As with spruce lumber, relatively little clear material develops; consequently the two plants mentioned are not producing sanded or face grades of plywood. One of the above companies has estimated that it could recover about five percent of its spruce volume in clear veneer, or veneer having only a few knots so that it could be improved by patching, to make face-quality veneer. This is not being done, however, because the volume does not make the present recovery of this grade worthwhile, nor do Association grade-marking rules. Similar results were indicated in a test of northern Alberta spruce made by the F.P.L.C. (9). O'n the other hand, from properly selected logs, a great deal of small and tight-knotted material develops that is particularly suited for use in sheathing plywood. This plywood has the advantage of being appreciably lighter than Douglas fir plywood, and consequently cheaper to ship. Also, it has a high strengthlweight ratio so that it can be used interchangeably with fir plywood in many places. In other places shorter spans or greater thickness must be used, just as with spruce lumber. As with spruce lumber, the color is attractive, although it must be admitted that the veneer-drying and hot-pressing operations cause some darkening of the wood.

8 FORESTRY CHRONICLE The F.P.L.C. have suggested cutting procedures for white spruce veneer (9). With proper care, excellent veneer can be produced from spruce. Drying problems are not serious, nor are they completely solved. High moisture content sapwood veneer should be segregated from heartwood veneer, and dried separately. This is standard practice for most species. Initial gluing problems arose in hot pressing, but these have been largely overcome with time and experimentation. There is some evidence that veneer should be glued-up soon after drying, and that inferior bonds can arise when dry veneer is stored for more than a few days. The principal defects are probably excessive knots followed by compression wood, spiral grain and pitch pockets. Spruce knots are hard, and may damage the knife unless logs are pre-heated. Plywood plants operating anywhere in Canada but in coastal British Columbia must have facilities for heating frozen logs in winter, so that it is relatively simple to extend log heating to be a feature of operations throughout,the year. The F.P.L.C. recommends the use of a micro bevel in the veneer knife as an aid to peeling this species (9). In order that a log be considered for plywood manufacture it must have the general features of being large enough to be worth placing in the lathe; it should be reasonably round and free of defects that impair cutting; and the veneer should be of useable quality. Since Douglas fir is the established softwood species, any evaluation of a new species for plywood manufacture would normally be a comparison with fir. How then does spruce compare with Douglas fir? Western spruces, at least, reach a size large enough to be considered peelable, even though smaller than the coastal Douglas fir. Although all logs are not necessarily of peeler quality, one company operating in the Interior of British Columbia estimates that their spruce is more free of ring and heart shake than the Douglas fir available to them, and more circular in cross section. The average yield or recovery of plywood from Interior Douglas fir logs is just under 50 percent of the cubic log volume, and is about the same for spruce. In addition, there is a freight advantage for spruce due to its lower weight and, in comparison with Coast-produced fir plywood, a lesser distance to most markets. Fir plywood still enjoys a price differential over other softwood plywoods, however, and according to Canadian Standards Association Specifications for western softwood plywood other than Douglas fir, only sheathing grades can use the grade mark "P.M.B.C." (Plywood Manufacturers Association of B.C.). It must be remembered that although the plywood industry of coastal B.C. has been increasing at a rapid rate, the volume of peelable Douglas fir logs is definitely restricted. One major producer has recently made an arrangement whereby that company will import peeler fir logs from Oregon. Expansion of the industry must come from coastal species other than Douglas fir, or in the mills away from the Coast. Probably both will take place. Species other than Douglas fir must have proper recognition. The white spruces are in a favorable position to take advantage of this change because of the size of the resource, its favorable location, and the fact that spruce is so eminently suited for sheathing which is now the major single item in the plywood market.

9 JUNE, 1960 Laminated Timber Another potential, but undeveloped, use for spruce is in the laminating industry. Because of its strength advantage and availability, Douglas fir is the species used almost exclusively in laminating. A minor amount of western larch is also used. It is stated that properly kiln dried spruce in the dimensions and grades required for laminating is hard to obtain, but there seems to be no obvious reason for this. It is true that members made of spruce must be larger than those of fir, to carry the same stresses, and it is considered currently that spruce offers no cost advantage over fir. Combinations of spruce and Douglas fir laminations offer possibilities. Spruce does have an advantage over both fir and larch in that it is generally more attractive in appearance. It is particularly suited to arches of moderate span (12). With the growing use of laminated timbers for their decorative qualities, spruce should have a potential in this field of utilization. Non-Paper Fibre and Miscellaneous Products Items made from wood fibres are normally classified as paper products and non-paper products. The distinction is not always clear, but the latter category may be considered to include such items as egg cases, paper plates and other moulded products (usually made from groundwood pulp or from re-used papers) and insulation boards and hardboards (made from mechanically defiberized wood or other fibrous material). The newer classification of particle boards does not originate from pulp, but rather from wood residues such as sawdust, planer shavings, macerated wood, or specially cut flakes. Spruce is an important ingredient of moulded products, in particular those in contact with foodstuffs, or where light color is a factor. The spruces are well suited for the manufacture of insulation boards and hardboards, but for the most part mills making these products are located in areas where spruce is more valuable for paper pulps. Excellent particle boards can be made from spruce. On the other hand, areas where large volumes of unused spruce, in either log or residue form, are available suffer the disadvantage of being remote from markets. Hence they would have the burden of high transportation costs for a bulky finished product. Two interesting but minor products are spruce gum and spruce oil. The former is an oleoresinous exudation obtained from black, red, and white spruce. The gum exudes from resin ducts in the sapwood, usually as a result of injury. Hardened lumps of resin are gathered by chipping or scraping them from the bark. If necessary they are cleaned by steaming and straining. Spruce gum is used in medicinal preparations and as a chewing gum. Spruce oils are obtained by steam distillation of needles and twigs of black spruce and white spruce. These oils are used in greases and shoe-blacking, and in liniments and other medicinal preparations (14). Because it is such an important part of the forest economy, what suggestions can be made to improve the utilization of spruce? Many of the problems are by no means unique to spruce but apply equally to other softwoods.

10 134 FORESTRY CHRONICLE A problem that cannot be ignored concerns the utilization of species associated with spruce in the forest stands. The true ks constitute the major volume of associated species, followed by jack or lodgepole pine and, in some areas, poplars. Each of these has its particular uses and its particular problems. It is cold comfort to the operator to leave him to solve his own problems in the utilization of less valuable species. At the Annual Meeting of 1956 a panel discussion was held entitled - "Unpopular Species and Their Increased Use," wherein some of these problems were discussed. The printed papers describe the increasing utilization of several of the less valuable species (22). The Canadian pulp and paper industry is large, soundly financed and well organized. It has a splendid research organization, available to all mills, and many companies have sizeable research laboratories of their own. Although the industry is faced with a complex of serious and changing problems, it has the resources to attack these with vigor. The sawmill industry, as the major counterpart in spruce utilization, is in much less satisfactory condition. It is composed of some 6,400 units of which some 200 are moderate to large in size and the remainder small and often extremely vulnerable to market changes. About 5,000 of these mills are each operated by three to four men under individual ownerships or partnerships (5). Many Canadian communities depend in large part on the existence of their local sawmills. Some of these mills fill a local or regional need for rough or partially finished lumber, but most lumber production is shipped to distant markets. It is a well recognized fact that the industry is disorganized, and that it is meeting stiff competition from other segments of the forest products industries, and from non-wood products. Lumber, as a product, is in a shrinking market, based on per capita consumption. The solution to this problem is complex, and should be tackled in several ways. The industry itself, through the regional associations, has set up the Canadian Wood Development Council in order to promote the use of wood. Representations have been made to the Federal Government at various times requesting further efforts in governmental research in forest products, and in disseminating the results of such research. Assistance has been requested in marketing forest products. Some of the sawmills are undergoing a transformation, and are showing the way toward more stable operation. Where a sawmill can integrate its production with that of a pulp mill, and preferably also with a plywood plant, better use of the raw material results. More complete utilization of the log is a necessity. Because of the attributes of spruce lumber, particularly of clear material, every effort should be made by operators to recover as much as possible from the log. The trend toward end and edge gluing of boards so as to manufacture engineered wood is well established. The development of spruce specialtypanel products has been noted. The inroads of plywood into the lumber sheathing market have resulted from saving in labor costs resulting from the use of panel products. There is a definite trend toward the pre-finishing of wood products, so that the customer has a minimum of time and expense in putting his purchase into use. In other words, the sawmill is running the gamut from

11 JUNE, the rough, green board factory to an efficient, at least partly automated, and integrated unit, producing a highly finished product. Spruce has good gluing properties, and the building up of larger dimensions and better grades offem no serious obstacles. This evolution can be speeded up with outside help, but for the most part it must come from the sawmills themselves, individually or, preferably, through group action. Many inefficient units will fall by the wayside but those with intelligent management should become stable industries. CONCLUSION The utilization of spruce is well established in the major fields of pulp and paper, and lumber. Spruce is used to a minor extent for specialties such as round timbers and railway ties. It is entering such fields as plywood manufacture where it will undoubtedly play an important part. It has a potential in timber laminating and particle board manufacture. The key to spruce utilization, as with most other species, is to utilize as much of the log as possible, to diversify the products, and to take advantage of as many high value specialties as is possible. As foresters, our duty is to see that the products of the forest are intelligently manufactured and marketed, so as to have a stable forest industry. LITERATURE CITED 1. ANDERSON, I. V Engelmann spruce--its properties, uses, and production. Intermountain For. and Range Exp. Sta., U.S. Forest Service. Res. Paper No pp. 2. Canada, Dept. Northern Affairs and National Resources Canadian woods, their properties and uses. Forestry Branch. 2nd Ed. Ottawa. 367 pp. 3. Canada, Dept. Northern Affairs and National Resources Native trees of Canada. Forestry Branch. Bull. No. 61 5th Ed. 293 pp. 4. Canada Dept. Northern Affairs and National Resources Forest and forest products statistics-canada. Forestry Branch. Bull. No. 106, Revised edition. 70 pp. 5. Canada, Dept. Northern Affairs and National Resources Minutes of proceedings and evidence. Standing Committee of Mines, Forests and Waters. Ottawa. pp Canadian Pulp and Paper Association Reference tables. May. 32 pp. 7. Canadian Standards Association Standard specification for round timber CSA Specification No. A nd reprint. 8. DROW, J. T Mechanical properties of Engelmann spruce. U.S. For. Prod. Lab. Rept. No pp. 9. FIEHL, A Cutting white spruce veneers for plywood. Canada, Dept. Northern Affairs and National Resources, Forestry Branch, For. Prod. Lab. Reprinted from Canadian Woodworker, Nov. 4 pp. 10. Forest Products Laboratories of Canada Strength and related properties of woods grown in Canada. For. Prod. Lab. Tech. Note No pp. 11. Forest Products Research Laboratory A handbook of softwoods. Dept. of Scientific and Industrial Research. London. 73 pp. 12. KENNEDY, D. E The construction and testing of a glued laminated wooden arch of 47-foot span. For. Chron. 24 (2): LUXFORD, R. F Use of Engelmann spruce for house constructio~~. U.S. For. Prod. Lab. Rept. No pp. 14. MARRIOTT, F. G Spruce gum. For. Prod. Lab. of Can., Ottawa. Nov. 6 pp. 15. PECK, E. C The nir drying of Engelmann spruce. U.S. For. Prod. Lab. Rept. No. R pp. (Contirrued on page 125)