Abstract: Apparatus, for extrusion of a mixture of wood particles and binder, including a compression chamber, in an extrusion press, for precompressing the mixture by a compression stroke transverse to the extrusion axis, the compression stroke being delivered by at least one precompression piston, wherein the improvement comprises mixing the mixture prior to precompression with elongated bits which will be acted on by an orienting influence in a known way so that the elongated bits are deposited substantially parallel to the extrusion axis, and performing the precompression of the outer layers of the mixture with a reduced precompression ratio so that the bits oriented prior to precompression remain fixed in position during the subsequent extrusion stroke.