It's Acorn Season! Please Help Out!


The Mighty OakAutumn is acorn season. The time for collecting acorns from our neighborhood's oak trees is upon us!! The Arroyo Seco Foundation humbly asks for your participation in gathering a paper bag's worth of acorns. If you have a great oak, particularly an Engelmann oak, in your year or neighborhood, please pitch in.



  • We are interested in acorns from Engelmann or Coast Live Oak trees. The Coast Live Oak is by far the dominant oak tree in the area, with the Engelmann being the other main variety.
  • Gather a small paper bag's worth of acorns
  • Put the acorns in a bowl of water. THROW AWAY those acorns that float on top. KEEP the acorns that sink down to the bottom!
  • Dry the acorns off completely
  • Put the acorns in a brown/dark paper bag, with a leaf from the tree inside the bag
  • Store the paper bag in your fridge
  • Give me a call to schedule delivery of the acorns to your local watershed coordinator

If you would like to learn how to identify the Engelmann Oak and Coast Live Oak, follow the link through and you can find out the characteristics of the trees, why they are important, and where to find them! Identifying Oaks


Thank you for your time and participation. My phone number is (925) 997-2896. I am available at any time. You can also respond to the e-mail address provided below, and I will get in touch with you immediately.


All the best,

Andy Byrne

Watershed Coordinator

Arroyo Seco Foundation

P.O. Box 91622

Pasadena, CA 91109

(925) 997-2896 (Mobile)

Andy@arroyoseco.org



The Pasadena Oak


The majesty of the Engelmann Oak can take your breath away. Their large twisted spreading limbs generally form a sparse crown. Their gray/green leaves are more elliptical or oval than the Coast Live Oaks, and their acorns more stubby. They often reside near Coast Live Oaks and Sycamores.


A separate species, Engelmann Oaks only exist in a narrow band that stretches along the foothills of Southern California from Pasadena down through Orange, Riverside and San Diego County into Baja California. They need to be twenty miles or more away from the ocean at an elevation of 500-4000 feet. In Southern California these spectacular trees have had a hard time because the mesas on which they are usually found are also ideal sites for homes.


Engelmann Oaks are probably the most imperiled of all tree oaks and are one of the most endangered natural plant communities in California.


This is the oak that was called the "Pasadena Oak" in Los Angeles County. It is also sometimes referred to as the "Mesa Oak."