Non-native and invasive plant species are invading our native habitat and open spaces. They aggressively compete with our native plants for resources and spreads rapidly once established. Monitoring, management, and removal of these plant species is an important aspect of land management and habitat restoration.

Help us to manage populations of invasive plants and remove them from the habitat. No previous experience is necessary, just a desire to work outside and get dirty! Snake chaps, gloves, and tools will be provided but please feel free to bring your own if you have them. Please wear long pants, long sleeved shirts, close toed shoes, and protective sun protection. Note: This is a wilderness area, there are natural hazards. Snakes, including rattlesnakes, are occasionally seen here.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-3 activity on the land.

Learn more and register here

Enjoy an evening hike through stunning rock formations and fragrant native plants as you listen to the sounds of nature. During this hike in the Irvine Ranch Open Space, you may travel at various hiking speeds based on your comfort level.  This out-and-back program travels 3.5 miles round trip up to scenic Loma Ridge and back down. Please bring a red-tinted flashlight as the return portion of the hike may be after sunset.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-3 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register here

Spend the morning in a beautiful oak woodland watering Coast Live Oak seedlings and native plants in Weir Canyon. To get to the planting site we will travel for 15 minutes in a safari style truck giving you majestic views of Weir Canyon. We may be using shovels and small handheld tools. No experience necessary.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-2 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register here

Ready for a workout? Forget the gym for the day and head outside! Join us for an exhilarating morning fitness hike on the paved Hicks Haul Road in OC Parks’ Irvine Ranch Open Space. This hike allows you to choose between a 3, 6, or 8 mile route, all of which are conducted at the speed of about 3.0 to 3.5 miles per hour. The footing on the asphalt paved road is smoother than dirt roads and single track trails normally found in Limestone Canyon Nature Preserve, but is beginning to show its age with cracks, crevices and an occasional dip. Otherwise, the terrain is smooth, so this is a great walk for anyone who wants a “wilderness experience” without getting dirty! The 6 and 8 mile routes experience two fairly steep ascents and descents. The 3 mile route takes you to the top of Loma Ridge and back down. Along the way, you will have sweeping views of much of Orange County and the Santa Ana Mountains. Various animals, like hawks, deer, and lizards are also frequently seen in this area.

Participants should be confident in their ability to hike 3, 6, or 8 miles at a steady pace. Please come prepared with proper hiking attire, ample water and adequate sun protection. Because of the paved surface, you may wear walking or running shoes instead of hiking boots. For the longer distances, at least 2 quarts of water (64 oz) is recommended. Ages 16 and up.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-3 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register here

Be prepared to experience the beauty and wonder of Weir Canyon, part of OC Parks’ Irvine Ranch Open Space, steeped in history and lore, on this morning equestrian ride. The ride will travel through Weir Canyon, where the trail weaves its way through a beautiful oak woodland inhabited by deer, coyote, bobcat, and many different birds. You will travel the route of the Butterfield Stage and see a monument dedicated to the Mexican ox cart drivers. If time permits, we will climb to the Two Tower vista point to look at distant views. This ride travels on wide trails with several easy to moderate climbs. Equestrians who have trail riding experience and their own fit and able horse are welcome. You will need to transport your horse to the staging area. Owners of unshod horses, please note that footing will include areas of gravel and distances over asphalt pavement. Please bring water on the ride.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-3 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register here

Join us on this moderate paced fitness hike in OC Parks Red Rock Wilderness Park. We will hike around 8 miles at a 3.5 mph pace through coastal sage brush and see views of the surrounding Limestone and Black Star Wilderness areas. This hike is designed for fit individuals who relish the challenge of a brisk outdoor adventure.  Please bring a minimum 70 oz. of water. Come prepared with a pack, sturdy closed-toed hiking shoes or boots, sunscreen, first aid, and all other supplies to keep you safe and healthy on the trail. Each participant must carry his or her own pack and water. Under-prepared participants may be denied access to this activity. Please bring red headlamp.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register here

Join us in the back-country wilderness for a journey filled with beautiful sights that are photographic and artistic sketching opportunities. Our journey begins in the afternoon. We will be deep in a secluded canyon, where time is measured in centuries, even millennia, in the sandstone cliffs of this ancient place called Limestone Canyon. You will board a 4-wheel drive vehicle for a 13-mile tour of the canyon and hills surrounding it. We will stop frequently for 15-30 minutes to admire the views, take photos, sketch landscapes, and answer questions.

Stops will include short walks with views of The Sinks, a trip up Cactus and Markel Spur, with optional, single track, one-mile hike into Box Springs or a 1.5 mile Markel Spur to East Sinks loop hike. Both the Box Springs and Markel Spur hikes provide the visitor a true back-country experience. An alternative, but similar, hiking trail may be used.

From the Augustine Staging Area, we proceed up an old ranch road that was paved to provide access to Irvine Lake and the mines in Black Star Canyon. At the research center, we head off-road up a narrow, windy, and sometimes bumpy trail to Loma Ridge and beyond. Bring your camera equipment, sketchbook, or just enjoy the ride.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-2 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register here

We start our ride through OC Parks’ Irvine Ranch Open Space on the paved Hicks Haul Road, the extension of Jeffrey Rd north of Portola Pkwy. As we warm up on the climb to the top of the road, we enjoy increasingly beautiful views over Irvine. We then follow Loma Ridge to the East, with fantastic vistas of Orange County, the surrounding wildlands, and even Catalina Island on clear days. From Loma Ridge, we descend on a single track to Box Springs which provides year-round water for wildlife like deer.

After the springs, we continue to the Sinks, Orange County’s own “Grand Canyon,” where we enjoy our snacks during a short break. On our way back, we ride along Limestone Ridge, a fun singletrack that leads us towards the Augustine Staging area, enjoying views of Saddleback and Santiago Canyon. From there we will climb back up to Loma Ridge, and then coast back down on the paved Hicks Haul Road to our starting point. Motorized recreation vehicles of any class or type are not permitted for use in the Nature Preserve.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register here

The Irvine Ranch Open Space Advanced Distance Hike series is designed for experienced hikers who thrive on long days, big climbs, and the satisfaction of pushing physical and mental limits. This hike covers approximately 15 miles with 3,300 feet of elevation gain, traversing some of the most rugged and remote sections of the Irvine Ranch Open Space. This route combines steep ascents, rolling ridgelines, and exposed terrain with panoramic views that make every step worth the effort.

This is not a casual stroll — it’s a test of endurance, pacing, and preparation. Participants should have prior experience with strenuous, half-day or full-day hikes and be comfortable navigating challenging terrain in varying conditions.

Self-Sufficiency is Required There are no water sources, food stations, or supply drops along this route. Every participant is responsible for carrying all the gear, water, and nutrition they will need for the day. We strongly recommend: Water: Minimum 70 oz per person (more in hot weather) Food/Snacks: High-calorie, easily portable items to sustain 6 hours of hiking (energy bars, trail mix, sandwiches, electrolyte chews) Gear: Closed-toe hiking shoes or boots, sun protection (hat, sunglasses, sunscreen), extra layers, basic first-aid kit, trekking poles (optional but recommended) Under-prepared participants may be denied access to the hike.

Pace & Timing Expect to be on the trail for 6 hours, with extended climbs and limited shade. A steady, sustainable pace is critical. We will take short breaks as needed, but hikers should be able to maintain consistent forward progress throughout the day.

Important Notes This hike is physically demanding and not suitable for beginners. There will be no early exit points — once you commit, you must be prepared to complete the route. Weather conditions can greatly affect difficulty. Hot days will make the climbs especially punishing; cold or wet weather can increase risk and exposure. If you’re ready for a true challenge, breathtaking views, and the camaraderie of fellow Sufferfest enthusiasts, join us for the Irvine Ranch Open Space Advanced Distance Hike Series— and earn every mile the hard way.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-5 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering.

Learn more and register here

Come explore OCParks’ Irvine Ranch Open Space. This scenic hike involves steep climbs and descents on both double and singletrack trails and around 1100’ of accumulated climbing elevation. Though challenging, the hike rewards you with sweeping views of the Irvine Ranch Natural Landmarks and Santa Ana Mountains. On clear days you can see Catalina Island and even beyond Orange County into the Los Angeles Basin.

Please arrive 15 minutes early, ready to hike; the Baker hiker entry gate will close promptly 5 minutes before the start time.

Please come prepared with a sturdy day pack, water, snacks, closed-toe hiking shoes or boots, sunscreen, first aid, and all other supplies to keep you safe and healthy on the trail. All participants must carry their own day pack and water and be comfortable hiking an average moving pace of 3 miles per hour.  Please make sure you bring around 70 oz. (2 quarts) of water and trail snacks. Under-prepared participants may be denied access to this program.

Please note that you will be asked to adhere to the following measures in order to participate:

• Be registered in advance, no walk-up registration is permitted.
• Arrive with all necessary equipment to keep you safe on the trail, including water, proper attire, and closed-toe footwear, first aid, health needs etc.
• Restrooms will be available, but facilities will not be sanitized for each individual.
• All participants are required to sign a liability waiver upon arrival at the staging area and before beginning the activity. The waiver can be previewed here: IRC Liability Waiver
• You may be prevented from participating if you do not adhere to the above protocols.

Additionally, in an effort to respect and protect all employees, volunteers, and participants, please do not sign up or attend if you are not feeling well, exhibiting any symptoms of illness or have been in recent contact with someone who was ill.

Reviewing the 1-through-5 Difficulty Ratings will help you evaluate your readiness to participate in this level-4 activity on the land. Please visit our FAQ page for answers to activity specific questions you may have prior to registering. To learn more about the staging areas and activity locations, please visit our Staging Areas Playlist page.

Learn more and register here