Abstract:

Three kinds of poplar clone wood, poplar 72(Populous ×euramericana cv. I-72/58), poplar 63, (P. deltoides cv. I-63/51) and poplar 69 (P. deltoides cv. I-69/55), growing in three different beaches of the Yangtse River (river beach, islet beach and lake beach) with three different planting densities (3m ×4m, 4 ×5m and 5m ×6m) were selected as the testing materials. The relationships between wood properties and quality of veneer and plywood were studied.The results show that in wood anatomical properties of poplar 72, poplar 63 and poplar 69, the variance of veneer thickness is very significantly related to the fiber width, the proportion of vessel and fiber at 0.01 level is significantly related to the fiber length, the thickness of cell wall, the ratio of cell wall to cell cavity, the ratio of cell cavity to cell diameter, the length of vessel and the proportion of ray at 0.05 level.The ratio of lathe check of veneer is very significantly related only to the diameter of cell cavity at 0.01 level, but not related to other anatomical properties. The gluing strength of plywood is very significantly related to the fiber length, the fiber width, the diameter of cell cavity, the thickness of cell wall, the radio of cell wall to cell cavity, the vessel length, the diameter of vessel in tangential, the microfibril angle and the proportion of vessel and ray at 0.01 level, and is significantly related to the proportion of fiber at 0.05 level. In wood chemical properties (pH value, acid and alkali buffer) of poplar 72, poplar 63 and poplar 69, the variance of veneer thickness and the ratio of lathe check of veneer are not related to chemical prperties, but the pH value of sapwood is significantly related to and the pH value of heartwood and the average pH value of sapwood and heartwood are very significantly related to gluing strength of plywood at 0.01 level, respectively. In wood physic-mechanical properties of poplar 72, poplar 63 and poplar 69, the variance of veneer thickness and gluing strength of plywood are not related to physic-mechanical properties, but the ratio of lathe check of veneer is very significantly related to the modules of elasticity at 0.01 level and is significantly related to the wood density in air-dry at 0.05 level.

Key words: Plantation of Poplar, Wood properties, Veneer, Plywood, Relationships between wood properties and quality of veneer and plywood