The Lake States of Michigan, Minnesota, and Wisconsin consist of 49.4 million hectares (122 million acres) of land, 19.8 million hectares (49 million acres) of which are forested, with 6% of those having been removed by law from timber production. Aspen (Populus tremuloides) is an important component of this resource. In recent years, a concern that the aspen cut will exceed its growth has surfaced. That is, Will the aspen supply be adequate to support the growing solid-wood, composite, and paper industries in the Lake States region? To satisfy the increased demand for forest products, it is expected that much of the future timber supply will be from improved trees grown on managed plantations. It is critical that the mechanical properties of this resource are clearly understood so that alternative uses of this material can be evaluated. A study was conducted using full-size lumber tests on 243 38- by 89-mm (2- by 4-in.; hereafter called 2 by 4 gass) boards cut, using two methods, from 50 logs to determine selected mechanical and physical properties of the Wisconsin-5 hybrid poplar clone. The material was either kiln dried or partially air dried followed by kiln drying. The 2 by 4 gass were assigned grades according to four grading rules: Light Framing, Structural Light Framing, Structural Lamination, and Machine Stress Rating. Results suggest that this poplar clone would produce visually graded material that is similar in properties and characteristics to the native aspen and cottonwood resource. Close to 65% of the material produced made grades of either Standard and better or No. 2. The Machine Stress Rating grade most likely to be produced from this material would be 1450f--1.3E. To avoid excessive degrade as a result of warping during drying, this material should be dried in flitch form.

Wood-based materials are CO2-neutral, renewable, and considered to be environmentally friendly. The huge variety of wood species and wood-based composites allows a wide scope of creative and esthetic alternatives to materials with higher environmental impacts during production, use and disposal. Quality of wood is influenced by the genetic and environmental factors. One of the emerging uses of wood are building and construction applications. Modern building and construction practices would not be possible without use of wood or wood-based composites. The use of composites enables using wood of lower quality for the production of materials with engineered properties for specific target applications. Even more, the utilization of such reinforcing particles as carbon nanotubes and nanocellulose enables development of a new generation of composites with even better properties. The positive aspect of decomposability of waste wood can turn into the opposite when wood or wood-based materials are exposed to weathering, moisture oscillations, different discolorations, and degrading organisms. Protective measures are therefore unavoidable for many outdoor applications. Resistance of wood against different aging factors is always a combined effect of toxic or inhibiting ingredients on the one hand, and of structural, anatomical, or chemical ways of excluding moisture on the other.

Acknowledgements -- References -- Chapter 5. Ecology and silviculture of poplar plantations -- Introduction -- Propagation and production of planting stock -- Planting stock types -- Stock production systems -- Unrooted dormant cuttings and sets -- Weed control strategies -- Fertilization and irrigation -- Crop health, protection, and hygiene -- Unrooted dormant branch cuttings -- Rooted dormant cuttings -- Container nursery for rooted plants -- Stock harvesting, processing, and quality control -- Harvesting -- Processing -- Quality control -- Stock packaging and storage.

In recent years wood strength researchers have begun to replace experimental unit allocation via random sampling with allocation via sorts based on nondestructive measurements of strength predictors such as modulus of elasticity and specific gravity. Although this procedure has the potential of greatly increasing experimental sensitivity, as currently implemented it can easily reduce sensitivity. In this paper we discuss the problem and we present solutions. Given the existence of nondestructive measurements of strength predictors, our methods can be used to reduce sample sizes. We have written a public domain computer program that implements the methods.