Join FOPOS for a special Earth Day cleanup event on Saturday, April 20th to celebrate our planet and help protect our local environment. This event will include two volunteer sessions (come to one or both!), as well as a community potluck and native plant giveaway.

Earth Day Cleanup Event Schedule:

• 10:00am-12:00pm - volunteer session

• 12:00-1:00pm - community potluck and native plant giveaway

• 1:00-3:00pm - volunteer session

About the volunteer sessions: teams of volunteers will tackle invasive species, such as multiflora rose and Japanese honeysuckle, that threaten the Billy Johnson Mountain Lakes Nature Preserve. Volunteers will also help plant native species and protect flowering native trees. Volunteers will work alongside FOPOS's stewardship team, including our director of natural resources and stewardship. Folks can expect to gain knowledge about plant identification and other stewardship skills. We look forward to seeing you this spring!

Sign up today.

Join FOPOS and local experts Matt and Shannon for a garlic mustard forage walk on Sunday, April 14th 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 invasive plant--and then we will get harvesting! Folks will get the chance 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.

Space is limited. Get tickets.

We’re thrilled to collaborate with the Arts Council of Princeton on a Plein-Air Painting Workshop in the Billy Johnson Mountain Lakes Nature Preserve, led by artist/instructor Raymond Brown.

Saturday, April 13 | 10am - 1pm
The workshop will meet at the Mountain Lakes House in the Mountain Lakes House at Billy Johnson Mountain Lakes Nature Preserve. 57 Mountain Avenue, Princeton, New Jersey.

Join the Friends of Princeton Open Space (FOPOS) and expert birder Winnie Hughes Spar for a spring 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; sign up today.

Join FOPOS and local experts Matt and Shannon for a garlic mustard forage walk 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 invasive plant--and then we will get harvesting! Folks will get the chance 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.

Space is limited. Get tickets.

NOW ON MARCH 30th!

Join FOPOS for a volunteer session on Saturday, March 30th! We’ll focus on timely forest and riparian restoration projects as we get the Preserve ready for the spring season.

Session 1: 10:00am-12:00pm
Session 2: 1:00pm-3:00pm

Sign up online.

As a part of the Great Backyard Bird Count, join Friends of Princeton Open Space (FOPOS) for coffee, hot chocolate, and a backyard bird feeder crafting event. This activity will take place on the beautiful patio at Mountain Lakes House, overlooking Mountain Lake, and it is open to all ages and abilities.

Folks will have the opportunity to view birds feeding on FOPOS's Great Backyard Bird Count feeders, and make their own pinecone bird feeders to take home.

All materials are included, just sign up and show up -- and enjoy crafting your own backyard feeder. Kids and adults will have the opportunity to spread seed butter on native pinecones, and roll the pinecones in the best birdseed for our local, native bird population. Kids and adults can then take their feeders home and enjoy welcoming birds into their backyards.

Get tickets.

Join FOPOS for a volunteer session on Saturday, March 9th! We’ll focus on timely forest and riparian restoration projects as we get the Preserve ready for the spring season.

Session 1: 10:00am-12:00pm
Session 2: 1:00pm-3:00pm

Sign up online.

** MOVED TO SUNDAY 2/18!! ** As a part of the Great Backyard Bird Count, join FOPOS and expert birder Winnie Hughes Spar for a guided bird walk in Princeton, NJ. Together, we will observe Princeton's birds and learn about their fascinating habits -- and learn how you can spot them from your very own backyard.

We'll spend time in our favorite places by Mountain Lakes House watching birds. Together with Winnie, we'll identify the birds, count them, and submit the information to Audubon to help scientists better understand and protect birds around the world. (If you already use eBird or Merlin, your submissions over the 4-day Great Backyard Bird count towards this.)

Winnie Hughes Spar has led bird walks for Washington Crossing Audubon Society and Princeton University Reunions, as well as annual Christmas bird counts in Princeton. She is author of the poetry chapbook Frost Flowers and teaches courses on literature and nature at the Watershed Institute.

Space is limited to 20 participants; be sure to sign up in advance.

SIGN UP ONLINE.

Show your LOVE for the Billy Johnson Mountain Lakes Nature Preserve this Valentine's Day by joining FOPOS for a volunteer stewardship session on Saturday, Feb. 10th!

Session 1: 10:00am-12:00pm
Session 2: 1:00pm-3:00pm

During this event, we will continue removing invasive plants such as Japanese honeysuckle, bittersweet vine, and multiflora rose. Invasive species do not have the same checks and balances here that they do in their homerange, and can completely overtake a site. The dense cover formed by invasive plants prevents young tree saplings from being able to grow into future canopy trees and degrades habitat quality for wildlife. Help us free some trees.

Sign up online.

Drop by the Mountain Lakes House this Friday, February 9th from 4:30-6:30pm to help our director of natural resources and stewardship sow native seeds.

Your assistance will help us prep for the busy 2024 season and ensure that we can plant many native species.

Please email FOPOS to sign up.

Join FOPOS for a volunteer session on MLK Day — Monday, January 15th, 2024! Volunteers will work with FOPOS’s stewardship team to advance timely forest and riparian restoration projects at the Billy Johnson Mountain Lakes Nature Preserve in Princeton, NJ.

We will have two two-hour sessions -- at 10:00am and 1:00pm. We hope you can join us.

Sign up online.

Join FOPOS for its final volunteer sessions of the year! Our December focus is protecting trees in the Billy Johnson Mountain Lakes Nature Preserve from busy beavers. Our goal is to protect 100 trees. The Municipality of Princeton is supporting FOPOS's tree protection efforts by supplying rolls of caging, stakes, wire cutters, and mallets. Volunteers will work with our stewardship team to cage trees and assist with invasive removal efforts along the lakeshore.

We will have two two-hour sessions -- at 10:00am and 1:00pm.

We hope you can join us, hot cocoa provided.

Sign up online.

Perspectives on Preservation Photo Exhibition will be on view in the Mountain Lakes Houses on December 2-3, 10-2pm. All are welcome to attend.

Perspectives on Preservation Photo Exhibition will be on view in the Mountain Lakes Houses on December 2-3, 10-2pm. All are welcome to attend.

Join us for a special evening to celebrate the extraordinary work by local photographers. Perspectives on Preservation is a refresh of Friends of Princeton Open Space’s beloved “Give Thanks for Nature” annual photo contest.

Join FOPOS for a fall volunteer session focused on invasive species removal. During this session, volunteers will work with FOPOS's stewardship team to perform riparian restoration as they enjoy time outdoors in the Preserve. As the seasons change, please note we will offer two time slots: 10am-12pm and 1pm-3pm.

Sign up online.

Join FOPOS’s new Chestnut Care Team! The Chestnut Care Team is a group of FOPOS volunteers focused on the Mountain Lakes American Chestnut population. During this series, we’ll learn more about this once-populous tree that produces the delicious nuts that many of us enjoy in the fall.

The planted chestnuts are part of a restoration project and are located within the deer enclosure of the 18-acre forest restoration project site at the Billy Johnson Mountain Lakes Nature Preserve.

Throughout these hands-on volunteer sessions, we will monitor the health of the local chestnut trees, learn how to ID the presence of blight, and help prevent the spread of blight. We will also remove invasive species and do other work as appropriate. With your help, we can help preserve this American treasure for future generations!

Sign up online.

Join FOPOS for a fall volunteer session focused on invasive species removal. During this session, volunteers will work with FOPOS's stewardship team to perform riparian restoration as they enjoy time outdoors in the Preserve. As the seasons change, please note we will offer two time slots: 10am-12pm and 1pm-3pm.

Sign up online.

Join FOPOS and South Jersey Wildlife Tours for an Eastern Screech Owl Walk at dusk on Friday, Nov. 3rd from 7:30pm-9:15pm.

Get tickets online.

Did you know that Eastern Screech Owls are one of the most common owl species in North America? Odds are you have one of these nocturnal neighbors mere miles (or less!) from your doorstep. During this experience, we will walk the trails at the Billy Johnson Mountain Lakes Nature Preserve in Princeton and listen and look for Eastern Screech Owls, learning much more about them along the way.

Space is limited to 20 participants; be sure to sign up in advance. Please note that this event is geared towards adults as it begins at 7:30 PM.

Join FOPOS’s NEW Chestnut Care Team! Together, a team of FOPOS land stewards will help preserve the Mountain Lakes American Chestnut Tree population, a species currently threatened by the non-native chestnut blight fungus.

The planted chestnuts are part of a restoration project and are located within the deer enclosure of the 18-acre forest restoration project site at the Billy Johnson Mountain Lakes Nature Preserve.

Sign up online.

What: The Chestnut Care Team is a group of FOPOS volunteers focused on the Mountain Lakes American Chestnut population. During this series, we’ll learn more about this once-populous tree that produces the delicious nuts that many of us enjoy in the fall.

How: Join us for a chestnut-focused volunteer session! The kickoff session will focus on recovering the American Chestnut Leaf Sculpture created by local ecological artist Susan Hoenig. The sculpture has become overgrown, and we’ll get a chance to free it from invasive weeds while nurturing native plants located within the plot. The artist-in-residence, Susan Hoenig, will be present and you can read more about her work and this sculpture online.

Throughout these sessions, we will monitor the health of the local chestnut trees, learn how to ID the presence of blight, and help prevent the spread of blight. With your help, we can help preserve this American treasure for future generations!

When: This series kicks off on Saturday, October 28th with a follow-up session on Nov. 11th.

We're thrilled to host a series of guided bird walks with FOPOS board member and friend  Winnie Hughes Spar. This bird walk will take place on Sunday, October 22nd. Together, we will wall the Preserve and observe Princeton's birds and learn about their fascinating habits!

Sign up online.. Space is limited - sign up today.

Join FOPOS for a fall volunteer session focused on invasive species removal. During this session, volunteers will work with FOPOS's stewardship team to perform riparian restoration as they enjoy time outdoors in the Preserve during peak fall weather. As the seasons change, please note we will offer two time slots: 10am-12pm and 1pm-3pm.

Sign up online.

Join Friends of Princeton Open Space for a festive Fall Fest fundraiser!

Funds raised will support paid summer internships for college students pursuing environmental majors, a program that helps train the next generation of environmental stewards; and for our new summer internship program for high school students.

Join FOPOS for a fall volunteer session focused on invasive species removal. During this session, volunteers will work with FOPOS's stewardship team to perform riparian restoration as they enjoy time outdoors in the Preserve during peak fall weather.

Sign up online.

Runners take your mark!

Join Princeton Athletic Club for the annual Mountain Lakes 5k Run + Walk in the beautiful Billy Johnson Mountain Lakes Nature Preserve benefitting Friends of Princeton Open Space.

Join FOPOS for a donation-based outdoor yoga class on Sunday, Sept. 10th at 10am. During this one-hour yoga class, Alisha Fowler (RYT 200) will lead you through an all-levels ashtanga-inspired flow, pairing breath and movement. As we do yoga together, we will take in the beautiful setting of the outdoors by Mountain Lakes House.

This class is donation-based and we kindly suggest a contribution of $10 or more. All donations support Friends of Princeton Open Space.

Get tickets.

As the fall migration season gets underway, we're thrilled to host a series of guided bird walks with FOPOS board member and friend  Winnie Hughes Spar. The first bird walk will take place on Sunday, Sept. 10th at 8:00am. Together, we will wall the Preserve and observe Princeton's birds and learn about their fascinating habits!

Sign up online. Space is limited - sign up today.

Join FOPOS for an early September volunteer session focused on invasive species removal -- aka, stop & chop!

During this Session, Volunteers will work with FOPOS's stewardship team to perform riparian restoration as they enjoy a nature walk in the Preserve. We'll stop along our route, chopping out invasives and learning about the importance of such efforts.

Sign up online.

Join FOPOS's stewardship team for an evening moth survey at the Billy Johnson Mountain Lakes Nature Preserve. Volunteering with FOPOS and lending his particular expertise will be Patrick Natale, Assistant Professor of Biology at Mercer County Community College.

Moths are fascinating creatures and contribute vital ecosystem services as pollinators and as prey, especially so for baby birds which primarily rely on caterpillars and other insects for food.

During this session, participants will observe, identify, and learn more about these mysterious night creatures. The program will begin with an educational presentation about moths, followed by a hands-on activity logging biodiveristy data at the Preserve.

Sign up.