Trees are some of the largest and most widespread organisms on Earth, yet the true number of their species has been an enduring mystery. This lack of knowledge is detrimental to conservation efforts.

Trees are some of the largest and most widespread organisms on Earth, yet the true number of their species has been an enduring mystery. This lack of knowledge is detrimental to conservation efforts.

WEST LAFAYETTE, Ind. — One person can’t measure all the trees in the world, but when many people come together, a global view becomes possible. A worldwide collaboration of scientists has produced the ...