Labile and easily biodegradable biochemicals are consumed preferentially. Plants constructed of these are rarely preserved. Cuticles Fossilization of Cuticle is NOT a random occurrence, but based upon original biochemistry. Burial in and of itself does not prevent continued degradation or further alteration. Cellulose components are reduced by hydrolysis with an increasing lignin component.
Geochemical alteration follows biological alteration.
The result is the precipitation of a spherical to elliptical concretion around the nucleating organic material. Crystallization of a variety of minerals on the cell walls and within the cell lumens results in the permineralization of the organic matter. Visit the Petrified Forest in Arizona as an example. Duripartic - When plant parts are able to withstand the degradational processes acting within their final resting area, the resistant plant parts are preserved with little alteration. When the internal organization of a plant part is degraded resulting in a void, this open area may act as a mold.