Youtube Button
Traffic Button
ListenLive Button


Partly Sunny
Partly Sunny
High: 72 °F
Low: 52 °F


Mostly Sunny
Mostly Sunny
High: 78 °F
Low: 54 °F


Mostly Sunny
Mostly Sunny
High: 83 °F
Low: 57 °F

SCV Outdoor Report: Smooth As A Baby's Bottom


By Wendy Langhans

A few weeks ago I was leading a hike in East/Rice Canyon.  Then it happened - an event guaranteed to strike terror into the heart of every hike leader - I was asked a question I couldn't answer.  A young girl asked, "Why is the inside of this acorn cap smooth?"

I stopped and took a look inside the acorn cap.  I rubbed the inside with the tip of my pinkie.   Sure enough, it was as smooth as a baby's bottom.

It was time to 'fess up, "I don't know, but I'll check into it and get back to you." So I did, Michelle, and here's what I've found out.  It turns out that not all acorn cap interiors have a smooth surface; some are hairy.  In North America, oaks can be divided into two groups:  white oaks and red oaks.  There are several ways you can tell them apart:

White Oaks - the inner surface of the acorn cap is smooth

acorns mature the year they are formed

acorns germinate in the autumn, after they fall from the tree

acorns taste sweeter (they have lower concentrations of bitter-tasting tannin)

To see some examples - go here.


A Valley Oak is a member of the "White Oak" group.

Red Oaks - the inner surface of acorn cap is hairy

acorns mature the year after they are formed

acorns germinate in the spring, after they fall from the tree

acorns taste bitter (they have higher concentrations of tannin)

To see some examples - go here.


Because this acorn germinated in the spring, it most likely came from a member of the "Red Oak" group.

I looked...but nowhere did I find a definitive answer as to why the inner surface of the acorn cap is smooth (or hairy).  However, I have a hunch (hypothesis) that I'd like to propose:  it has to do with how long it takes for the acorn to mature.  A red oak acorn (with a hairy cap) overwinters on the oak tree.  But just like the knit cap you wear on your head, an acorn's hairy cap has empty spaces for air.  And just like a knit cap provides insulation for your head on a cold winter day, the air inside an acorn cap may also provide insulation for the acorn.  Now mind you, this is just a hunch, but it's the best I could come up with for now.  I'll keep looking.



Upcoming Outdoor Events:

Saturday, December 19, 8 - 10 AM.  Bird Walk at Towsley Canyon.  It takes some unique birds to stick around in our winters.  Meet at the front entrance to the park.  Beginners are welcome.  For map, click here.

Sunday, December 27, 1-3 PM.  Take a look at Mentryville's Past.   Come share a bit of California history with your out-of-town guests as we explore historic Mentryville.  Meet at the first parking lot after the entrance to Pico Canyon.  For a map, click here.


You can listen to stories like this every Friday morning at 7:10 a.m. on "The Hike Report", brought to you by your hometown radio station KHTS (AM1220) and by the Mountains Recreation and Conservation Authority.

For the complete MRCA hike and activity schedule and for trail maps, click here or go to www.LAMountains.com.