Druse (botany)

A druse is a group of crystals of calcium oxalate,[1] silicates, or carbonates present in plants, and are thought to be a defense against herbivory due to their toxicity.

Calcium oxalate (Ca(COO)2, CaOx) crystals are found in algae, angiosperms and gymnosperms in more than 215 families.

These plants accumulate oxalate in the range of 3–80% (w/w) of their dry weight[2][3] through a biomineralization process in a variety of shapes.

[5] Druses are also found in leaves and bud scales of Prunus, Rosa,[6] Allium, Vitis, Morus and Phaseolus.

Still, it has been suggested that a number of factors influence crystal shapes and growth, such as proteins, polysaccharides, and lipids or macromolecular membrane structures.