Join the Friends of Princeton Open Space (FOPOS) and local foraging experts for a Mugwort Foraging Event at the Billy Johnson Mountain Lakes Nature Preserve in Princeton.

In this hands-on event, participants will delve into the world of the invasive plant, Mugwort. Under the guidance of our stewardship team and local foraging experts Matt and Shannon, participants will learn how to properly identify mugwort, sample a recipe, and safely remove it from designated restoration areas at the preserve. From teas to donuts to savory dishes, discover how mugwort can enhance your kitchen creations.

Sign up for this session via Eventbrite.

Join the Friends of Princeton Open Space (FOPOS) and expert birder Winnie Hughes Spar for a guided bird walk through the Billy Johnson Mountain Lakes Nature Preserve in Princeton, NJ. Together, we will observe Princeton's birds and learn about their fascinating habits!

Space is limited to 20 participants; be sure to sign up in advance. Please note that this event is geared towards adults. This event is weather permitting.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a weekday volunteer land stewardship session on Wednesday, June 4th from 10 AM - 12 PM.

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecological restoration work and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve.

Sign up for this session via Eventbrite.

Looking to register for multiple volunteer sessions this season? Register HERE.

Join us for our May Nature Walk through the trails of the Billy Johnson Mountain Lakes Nature Preserve.

Led by the Friends of Princeton Open Space stewardship team, this guided walk will offer a chance to explore lush trails, vibrant spring blooms, and the sights and sounds of nature as the season comes alive. Whether you’re a seasoned hiker or a first-time visitor, it's the perfect way to enjoy the outdoors and reconnect with nature. Our stewardship team will also share insights into the history of the preserve and the ongoing land stewardship efforts that help protect this special place for future generations.

Be sure to wear sturdy, weather-appropriate footwear. Feel free to bring a camera or binoculars along to help you spot and capture the beauty of wildlife as we explore.

Sign up for our May Nature Walk on Eventbrite

Join Friends of Princeton Open Space (FOPOS) at the Mountain Lakes House for a book club dedicated to readings about conservation, stewardship, and our relationship with nature.

Led by Diana Newby, FOPOS volunteer and faculty member in Princeton University's Writing Program, we'll spend our time together discussing Barbara Kingsolver's novel Prodigal Summer.

Sign up for our FOPOS Book Club on Eventbrite

Join the Friends of Princeton Open Space (FOPOS) for a weekday volunteer stewardship session on Wednesday, May 28th 1 PM - 3 PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecological restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve.

Spring is here! Volunteers will head out to one of our forest or riparian restoration sites for critical tasks such as invasive species removal, spring planting, or installing cages around native plants to protect them from deer & beaver browse. If you’re looking for a fun way to spend time outdoors and make a real difference, this is the perfect chance to get involved and help protect our local ecosystem.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a volunteer stewardship session on Saturday, May 24th, 2025. There will be two sessions, 10AM - 12PM or 1 PM - 3 PM. Come to one or both!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecosystem restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve. We will focus on timely efforts and maintaining our natural lands

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a weekday volunteer stewardship session on Wednesday, May 21st 10 AM - 12 PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecological restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a weekday volunteer stewardship session on Wednesday, May 14th 1 PM - 3 PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecological restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve.

Sign up online.

Join Friends of Princeton Open Space (FOPOS) for a backyard bird feeder crafting event. This hands-on activity will take place on the beautiful patio at the Mountain Lakes House, and it is open to all ages and abilities.

Stop by any time between 11am - 1pm and make a pinecone bird feeder to take home. We will have trail maps available if you want to take a walk and connect with nature. Feel free to pack a picnic lunch and enjoy the day at the Billy Johnson Mountain Lakes Nature Preserve.

Thank you Whole Earth Center for donating the sunflower butter for this community event!

Sign up for our Drop In Nature Craft

Join the Friends of Princeton Open Space (FOPOS) for a volunteer stewardship session on Saturday, May 10th, 2025 from 1 PM - 3 PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecosystem restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve. We will focus on timely efforts and maintaining our natural lands

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) and local experts Matt and Shannon for a Dame's Rocket Forage Walk at the Billy Johnson Mountain Lakes Nature Preserve in Princeton.

In this engaging event, participants will delve into the world of the invasive plant, Dame's Rocket. Led by knowledgeable guides, you'll learn how to identify this invasive species and taste-test a recipe using this plant -- and then we will get harvesting! We will work to remove Dame's Rocket in our pollinator garden since it is out-competing our native plants and decreasing biodiversity.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a weekday volunteer stewardship session on Wednesday, May 7th 10 AM - 12 PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecological restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) and expert birder Winnie Hughes Spar for a guided bird walk through the Billy Johnson Mountain Lakes Nature Preserve in Princeton, NJ. Together, we will observe Princeton's birds and learn about their fascinating habits!

Space is limited to 20 participants; be sure to sign up in advance. Please note that this event is geared towards adults. This event is weather permitting.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a weekday volunteer stewardship session on Wednesday, April 30th 1 PM - 3 PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecological restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) and local experts Matt and Shannon for a garlic mustard foraging & land stewardship session at the Billy Johnson Mountain Lakes Nature Preserve in Princeton.

During this stewardship session, participants will learn about the origins of garlic mustard and how to identify this plant. We will spend some time removing this tasty, but invasive plant that threatens the biodiversity at the Preserve and crowds out native plants. Folks will be able to take their garlic mustard harvest home, as well as taste some homemade garlic mustard pesto (compliments of Matt and Shannon). A recipe card will be included so that you too can make this unique and delicious recipe at home.

Sign up online.

Postponed to 4.27.25 due to storm forecast

Join FOPOS for a special Earth Day Land Stewardship volunteer event at the Billy Johnson Mountain Lakes Nature Preserve in Princeton, NJ.

Volunteers will work under the guidance of FOPOS’ stewardship staff to perform riparian and forest restoration, and plant native species in the Billy Johnson Mountain Lakes Nature Preserve.

We have two volunteer sessions: 10am-12pm and 1pm-3pm. Please pick the time slot that works best for you! From 12-1pm, join us for a community potluck and native plant giveaway!

Sign up online.

Join us for our April Nature Walk through the trails of the Billy Johnson Mountain Lakes Nature Preserve.

Led by the Friends of Princeton Open Space stewardship team, this guided walk will offer a chance to explore lush trails, vibrant spring blooms, and the sights and sounds of nature as the season comes alive. Whether you’re a seasoned hiker or a first-time visitor, it's the perfect way to enjoy the outdoors and reconnect with nature. Our stewardship team will also share insights into the history of the preserve and the ongoing land stewardship efforts that help protect this special place for future generations.

Be sure to wear sturdy, weather-appropriate footwear. Feel free to bring a camera or binoculars along to help you spot and capture the beauty of wildlife as we explore.

Sign up for our April Nature Walk on Eventbrite

Join the Friends of Princeton Open Space (FOPOS) for a volunteer stewardship session on Saturday, April 19th, 2025 from 10AM - 12PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecosystem restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve. We will focus on timely efforts and maintaining our natural lands

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a volunteer stewardship session on Saturday, April 12th, 2025 from 1PM - 3PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecosystem restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve. We will focus on timely efforts and maintaining our natural lands

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) and local experts Matt and Shannon for a garlic mustard foraging & land stewardship session at the Billy Johnson Mountain Lakes Nature Preserve in Princeton.

During this stewardship session, participants will learn about the origins of garlic mustard and how to identify this plant. We will spend some time removing this tasty, but invasive plant that threatens the biodiversity at the Preserve and crowds out native plants. Folks will be able to take their garlic mustard harvest home, as well as taste some homemade garlic mustard pesto (compliments of Matt and Shannon). A recipe card will be included so that you too can make this unique and delicious recipe at home.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a weekday volunteer stewardship session on Wednesday, April 9th 10 AM - 12 PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecological restoration work and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve.

Spring is here! Volunteers will head out to one of our forest or riparian restoration sites for critical tasks such as to invasive species removal, spring planting, or installing cages around native plants to protect them from deer & beaver browse. If you’re looking for a fun way to spend time outdoors and make a real difference, this is the perfect chance to get involved and help protect our local ecosystem.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) and expert birder Winnie Hughes Spar for a guided bird walk through the Billy Johnson Mountain Lakes Nature Preserve in Princeton, NJ. Together, we will observe Princeton's birds and learn about their fascinating habits!

Space is limited to 20 participants; be sure to sign up in advance. Please note that this event is geared towards adults. This event is weather permitting.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a weekday volunteer stewardship session on Wednesday, April 2nd 10 AM - 12 PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecological restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a volunteer stewardship session on Saturday, March 29th, 2025 from 1PM - 3PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecosystem restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve. We will focus on timely efforts and maintaining our natural lands.

Sign up online.

Join us for our March Nature Walk through the trails of the Billy Johnson Mountain Lakes Nature Preserve.

Led by the Friends of Princeton Open Space stewardship team, this guided walk will offer a chance to explore the Preserve as spring emerges and the land wakes up from its winter rest.

Be sure to wear sturdy, weather-appropriate footwear. Feel free to bring a camera or binoculars along to help you spot and capture the beauty of wildlife as we explore.

Sign up for our March Nature Walk on Eventbrite

Join Friends of Princeton Open Space (FOPOS) at the Mountain Lakes House for a new book club dedicated to readings about conservation, stewardship, and our relationship with nature.

We'll spend our inaugural meeting discussing Robin Wall Kimmerer's Braiding Sweetgrass: Indigenous Wisdom, Scientific Knowledge, and the Teachings of Plants.

Sign up for our FOPOS Book Club on Eventbrite

Join the Friends of Princeton Open Space (FOPOS) for a volunteer stewardship session on Saturday, March 22nd, 2025 from 10AM - 12PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecosystem restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve. We will focus on timely efforts and maintaining our natural lands.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a weekday volunteer stewardship session on Wednesday, March 19th 1 PM - 3 PM!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecological restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve.

Spring is almost here, and it’s time for our March clean-up! Volunteers will head out to the forest restoration site to remove invasive species like wineberry, multiflora rose, and English ivy. These plants are crowding out the native trees and shrubs we’ve worked hard to plant, including paw paw, persimmon, and flowering dogwood. If you’re looking for a fun way to spend time outdoors and make a real difference, this is the perfect chance to get involved and help protect our local ecosystem.

Sign up online.

Join the Friends of Princeton Open Space (FOPOS) for a volunteer stewardship session on Saturday, March 15th, 2025!

Volunteers will work under the guidance of the FOPOS stewardship staff to perform ecosystem restoration and invasive species removal in the Billy Johnson Mountain Lakes Nature Preserve. We will focus on timely efforts and maintaining our natural lands

We have two volunteer sessions:

Session 1: 10 AM - 12 PM
Session 2: 1 PM - 3 PM

Sign up online.