checks u201d or u201c checking u201d as used herein refer to lengthwise separation and opening between fibers in a wood particle u201c surface checking u201d may occur on the lengthwise surfaces a particle that is on the l u00d7 w surfaces and u201c end checking u201d occurs on the cross grain ends w u00d7 h of a particle the term u201c skeletal surface area u201d as used herein refers to the total surface area of a wood particle including the surface area within open pores formed by checking between plant fibers in contrast u201c envelope surface area u201d refers to the surface area of a virtual envelope encompassing the outer dimensions the particle which for discussion purposes can be roughly approximated to encompass the particle 39 s extent volume dimensions the term u201c field moisture content u201d refers to veneer that retains a harvested moisture content above the approximately 30 fiber saturation point below which the physical and mechanical properties of wood begin to change as a function of moisture content such a veneer has not been dried below its fiber saturation point and then rehydrated e g by soaking in water the adjectives u201c green u201d and u201c seasoned u201d indicate veneers having moisture contents of more than or less than 19 respectively the term.