Pine trees begin growing in the spring. Some species of pine grow new shoots in the form of a crucifix in the days before Easter---late March or early April. Whether or not a pine tree produces shoots in the form of a crucifix depends on the species, the local weather and its geographical location.
The "cross" or lateral growth of the new pine tree shoots is not the same for all species. Most pine species have a double lateral growth and so do not resemble a crucifix. Loblolly pines, widespread in the southern United States, and ponderosa pines, found in the west, do produce new shoots in the form of crosses.
Phytochrome, a pigment in pine trees, responds to the relative length of daylight and darkness, thus telling the trees when it is time to begin growing in the spring. New shoots on pine trees in North Africa appear weeks before they do in Norway or Canada. In Australia, Chile, Argentina and South Africa, all in the southern hemisphere, Easter appears in the autumn when pine trees are not producing new shoots. In North America, new shoots begin growing in Georgia well before they do in Canada.
Elevation and Weather
Pine trees at lower elevations begin growing before they do at higher elevations. A harsh, prolonged winter in some northern locations might delay the growth of pine trees past Easter.
Cause of the Cross
Botanist David Hershey states that pine trees have a natural cycle of growth. The trees begin growing in the spring, prosper during the summer, slow their growth in the fall, and stay dormant in the winter. Scientists do not know the precise reason why new shoots on these particular species of pine look like crosses, but there is no scientific evidence that trees have any knowledge of human religious customs. Nevertheless, some Christians have concluded that crosses appearing on pine trees near Easter are divinely inspired.
Pine trees that yield crosses near Easter are among other plants whose growth and blooming are associated with holidays. There are species of cacti that bloom near Easter, Thanksgiving and Christmas, the Easter lily blooms near Easter. and the poinsettia is at its most colorful during the Christmas holiday.