Plant sampling (biogeochemistry) is an effective method of exploration – called the Biogeochemical Method.
Root systems of the plants collect the water which contain mineral rich nutrients. Depending on the size of the plant and particularly the size of its root system, this can provide the geologist with a significant geochemical signature. Factors to be considered include collecting a single species and sampling the same part of this species in order to compare “apples with apples”; also the same age of plant and same time of year. Vegetation sampling in some instances can replace soil sampling in areas where obtaining a proper soil sample is not possible.