The Pine Trees Always Leaning Towards The Equator

They are called Cook pines ‹Araucaria columnaris> and can be found in many parts of the world. They are tall and do not seem to grow straight. They come from New Caledonia, a tropical archipelago in the Southwest Pacific Ocean. The trees were first registered in the second mission of Captain James Cook.

The Pine Trees Always Leaning Towards The Equator : These pines are a popular choice for parks and gardens. They can reach the height of sixty meters and because of their small branches they have a distinct narrow look. But they stand out for their inclination that looks like they … drunk! Whether they are in the northern hemisphere or in the south.

The scientific observation was initiated by botanist Matt Ritter, of the State University of California. His curiosity was motivated when he saw the pines in California and Hawaii leaning south. His colleagues, on the other hand, told him that the slope in the southern hemisphere is heading north.

Ritter took the matter seriously, and along with his team, made measurements of 256 trees in eighteen regions across five continents, among them New Caledonia. Researchers excluded trees from their measurements, whose development could be affected by another object, such as a building.

They recorded the height of each tree, the diameter of the trunk, the direction of the compass and the extent of the slope. Scientists were surprised when the Cook pines were more systematically inclined than they could expect. “We have unveiled a surprisingly consistent pattern,” the team said.

On average, the pines climb 8.05 degrees, leaning southwards in the northern hemisphere and in the opposite direction in the southern hemisphere. Less than 9% of the trees measured were not consistent with this pattern.

Indeed, it was found that the latitude plays a significant role: The farther the equator was growing, the greater the slope.

Many plants are known for their tendency to lean toward a light source. However, there is a feature that helps trees stay upright: it’s their ability to detect gravity on a molecular level and therefore to direct the roots and stems in the right directions.

Even if a small tree develops a slope towards the sun, but as it matures, it tends to correct this asymmetry and to grow up, unless there is an environmental force that prevents it, such as strong winds.

It is likely that the Cook pines have a genetic quirk that allows them to bend, seeking more sunlight. But scientists believe that in addition to gravity, the Earth’s magnetic field can play a role.

The study was published in the scientific journal Ecology.

Source: Science Alert / Science.howstuffworks / New Scientist / Ecology First image Christian Defferrard