High density panels obtained by pressing wood veneers together in plywood or laminated veneer lumber (LVL) assembly configurations, at temperatures of 225°C to 250°C, high pressure and long press times, as long as 60 min or longer, have been shown by tensile tests, X-ray microdensitometry and scanning electron microscopy to present interphases where wood has welded just by application of the press heat alone. Short press times under the same conditions of pressure and temperature yield poor welding, or no welding at all, in the veneers interphases.