This enhanced image of a cross section of a pine stem shows the growth of the plant’s inner and outer tissues. It also demonstrates how frequently circles appear in the natural world, as the growth of the pine pushes out nearly equally from the center point. It’s not a perfect circle, but you could calculate the circumference of this stem by using the mathematical constant we call ‘pi.’ Why call out pi? Because today is Pi Day, an observance that’s been around since at least 1988, when the staff of the San Francisco Exploratorium first organized a march to celebrate the date: March 14, aka 3/14, an approximation of 3.14, the first three digits of pi.
Garry DeLong/Getty Images1.0.j17
A pine is any conifer in the genus Pinus,, of the family Pinaceae. Pinus is the sole genus in the subfamily Pinoideae. The Plant List compiled by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accepts 126 species names of pines as current, together with 35 unresolved species and many more synonyms.
Scientific name: Pinus Biological classification: Genus Consists of: Ducampopinus · Strobus · Pinus Belongs to: Pinaceae