You are a forester charged with increasing productivity in a South American forest newly planted with pines from Oregon. You believe that the southern forest lacks the fungal diversity needed by the North American pines, and that this lack of fungi is affecting the pines' productivity, but you have no evidence to support your ideas. To count how many fungal species were present in the Oregon forest, which methodology would you choose, and why?
A) Do direct sequencing on representative soil samples from across the forest.
B) Collect all the fruiting structures mushrooms, morels, etc.) found aboveground.
C) Expose the trees to radiolabelled CO2 and then collect the soil samples with the greatest radioactivity and do direct sequencing.
D) Count all the plant species and multiply by six, as David Hawksworth did when determining the ratio of fungal to plant species in England.