Four Harvard workers rake leaves into a disposal truck during a yard-wide leaf removal near the Science Center on Tuesday afternoon.

The fallen leaves that carpet Harvard Yard as the weather grows colder serve a purpose beyond offering a colorful treat for the eyes. The leaves, which are gathered up every year by Landscape Services, a unit of Harvard Campus Services, will be converted to soil and mulch that will nourish the Yard.

Under the direction of Landscape Services, workers for Facilities Maintenance Operations are currently engaged in the annual task of raking, blowing, sweeping, and collecting leaves on a daily basis across campus.

The collected leaves will be ferried away from the Yard—to the Arnold Arboretum in Boston, where they will be made into nutrient-rich mulch. But though they will be laboriously transported away from Cambridge, the transformed leaves will eventually return to their roots. Landscape Services will place the resulting mulch, sent back from the Harvard-owned arboretum, across the University’s grounds, according to Michael D. Conner, the director of strategic planning and communications for University Operations Services.

According to the Harvard Campus Services website, FMO recently expanded its organic landscaping program to produce over 100 tons of high-quality mulch—enough to satisfy the landscaping needs of all of Harvard Yard.

Not just the fall foliage is part of this production process. FMO collects all of the College’s herbaceous and woody materials for composting, along with a growing portion of food waste from dining halls and cafeterias, according to the Campus Services website.

The recycling of leaves picked up in the Yard, according to Conner, is a “key component” of the organic landscaping initiative.

“[This is] the busiest time of year,” said Luke R. Leighton moments after climbing down a ladder from the roof of Wigglesworth Hall, where he was cleaning fallen leaves out of a gutter. Leighton works for W.S. Aiken, an outside company contracted solely for rooftop jobs.

FMO employees take care of the leaves everywhere else. Anthony J. Pacillo, the senior manager of Harvard Yard and freshman dormitories, said that the schedule and method of leaf pick-up varies from year to year.

“Every fall is different,” Pacillo said. “A lot of it’s weather-dependent.” Both Connor and Pacillo declined to provide information about the number of hours spent by FMO workers gathering leaves or the cost of leaf pickup.