Two hundred oak tree seedlings to be planted in OC Parks' Limestone Canyon this winter as an ongoing effort to rehabilitate valuable oak woodlands 

Earlier this year, Irvine Ranch Conservancy (IRC) embarked on a new restoration project in OC Parks' Limestone Canyon with a goal to rehabilitate oak woodland habitats in the area. The Conservancy received approval to plant 500 acorns at the Augustine Staging Area Nursery in Limestone Canyon, growing the acorns into seedlings that will then be planted in the Limestone Canyon Nature Preserve.

Irvine Ranch Conservancy enlisted the help of IRC volunteers and members of the general public, in addition to Conservancy staff, to plant locally-sourced acorns from oak trees throughout the area in the Augustine Nursery that would grow into seedlings in time for planting in the winter.  

“Before the pandemic, volunteers planted approximately 480 Coast live oak acorns and helped water the seedlings,” said Irvine Ranch Conservancy Project Coordinator Matilde De Santiago. “Since the pandemic hit, all watering and care of the acorn seedlings has been done by IRC staff. The care includes watering, weeding, and removing pests from the seedlings to ensure their health and survival for the winter plantings.”

The acorn seedlings were untouched during the recent Silverado Fire, which did not cause any damage to the Augustine Nursery. About 200 of the acorn seedlings from the nursery are currently on track to be planted during the winter season - some as early as December. The oak restoration project in Limestone Canyon is more important than ever, as the seedlings will now help with wildfire recovery efforts.

Irvine Ranch Conservancy staff and volunteers are preparing to plant the seedlings in a meadow adjacent to Limestone Canyon road and in Agua Chinon Canyon. Once it is safe to resume public activities, Irvine Ranch Conservancy looks forward to welcoming members of the local community to help these oak seedlings continue to thrive.

“The plan is to have IRC volunteers assist in the plantings along the Limestone Canyon road meadow, and having volunteers and members of the public involved in the maintenance and care, thereafter, for years to come until the trees become well established,” said De Santiago.

Oak woodlands are an important part of the local habitats found on the Irvine Ranch Natural Landmarks. Not only will these new oak trees enhance the beauty of the landscape, but they will also provide a crucial source of food and shelter for native wildlife in Limestone Canyon.

To learn more about Irvine Ranch Conservancy and restoration work on the Landmarks, visit


Irvine Ranch Conservancy 

Irvine Ranch Conservancy is a non-profit, non-advocacy organization created in 2005 to help preserve and support the Irvine Ranch Natural Landmarks, enhancing the public’s connection to the land while helping partners and landowners with all aspects of stewardship. The Conservancy offers a variety of free, guided outdoor programs for all nature enthusiasts including hiking, mountain biking, horse-back riding and much more. For more information, visit