Damien Carré, one of the Ascending the Giants arborists, climbs a rope past branches on the way to the top of the Big Tree in La Pine State Park last Saturday.

Amid snowfall and freezing temperatures, members of Ascending the Giants — a nonprofit that finds and records Oregon’s biggest trees — climbed a rope into the crown of La Pine State Park’s Big Tree in an effort to verify its title as the largest ponderosa pine in the United States. If no greater score is submitted from elsewhere by March 15, the Big Tree will officially be the largest of its species in the country.

The team took measurements of three kinds. Jason Morrow, left, measured the height (167 feet); Brian French, below, wrapped the tape around the tree at “breast height” to determine the circumference (348 inches); and, from the ground, the team calculated the crown spread, or the spread of its branches at their widest (68 feet).