Learning Nature’s Earth and Water Secrets at the San Dimas Experimental Forest
By Ginny Heringer
May/June 2012

On Saturday, March 24, a group of eight from the Sierra Club’s Pasadena Group and Natural Science Section visited the San Dimas Experimental Forest (SDEF) in the foothills above Glendora for a tour with Forestry Technician Michael Oxford. The forest is not open to the public, and this was a special opportunity arranged by David Czamanske.

Mike met us at the locked gate and we drove to our first overlook point, on the south-facing slope overlooking the drainage of Big Dalton Canyon. There Mike pointed out three sections of visibly different vegetation on the hillsides and told us about the original purpose of the Experimental Forest.

In the 1930’s, city water engineers and the citrus growers in the flatlands below were concerned about the functions of mountain watersheds. How do they work? How does rainfall get from the higher elevations to the reservoirs and fields below? And how can land agencies best manage these important watersheds?

So, foresters, soil scientists and hydrologists began to experiment with type-conversions -- the removing of native plants and replanting of different types of vegetation on selected land areas. Comparable small watersheds were selected; two test sites and one control site. Heavy equipment and chemical defoliants were used to remove the natural vegetation from the test sites and then they were replanted with non-native shallow root grasses. This was to see if they could increase the amount of water flow to the flatland below. Today, after many decades these type-conversion areas have evolved into mostly buckwheat and sumac while the heavy chaparral like chamise and ceanothus have yet to be reestablished fully.

This heavy-handed manipulation of the watershed is hard to imagine today, but at the time, the experiment seemed reasonable and was in fact successful in delivering more water to the fields below. But scientists soon realized that more water runoff meant more erosion and debris flow.

Other studies began after the 1960 Johnston Fire to help address these concerns. Still, experimentation continued on the water usage of different plants.

Our next stop was the Tanbark Flats Research Station, where we saw a giant structure called a lysimeter, consisting of 26 planting plots connected to water collection tanks in a cement tunnel below, three tanks for each planting plot, one to collect rain, one to collect run-off, and one to collect seepage. With different plants in each plot, scientists could compare how water moves through the soil of each plant. This area is no longer in use for its original purpose but has been used in soil studies, and a smaller version of the lysimeter nearby is currently in use by a USC graduate student.

Annually, about 20 undergrad and graduate students and researchers in all are using the SDEF and the facilities at Tanbark Flats to do experiments. The research and monitoring facilities include rain gauges, stream gauges, debris dams, water quality samplers, a weather station, and the historic lysimeter complex.
According to the website, past and present research topics include watershed hydrology, biogeochemical cycling, fire effects, chaparral ecology, water yield, precipitation monitoring, post-fire erosion control treatments, soil non-wetability, hillslope erosion and watershed sediment fluxes, soil nutrient cycling, and bird habitat use.

The facilities were constructed mainly by the Depression-era Civilian Conservation Corps and Work Projects Administration labor programs and have the usual CCC charms of rock and woodwork in a lovely streamside setting. It is recognized as a Biosphere Reserve by UNESCO's Man and the Biosphere program.
This visit was truly a unique and fascinating experience. From now on, when I hike past debris dams and rain gauges in the forest, I’ll have a better understanding of the purpose of these structures and the science behind them. It was clear from the visit that human beings still have a lot to learn about nature. Thanks to Mike Oxford for our tour and to David Czamanske for organizing the trip.

For more information and photos of the San Dimas Experimental Forest, Google “San Dimas Experimental Forest: A Vision,” a publication of the U.S. Department of Agriculture.

Confronted with an adverse court ruling, the U.S. Forest Service has made no immediate move to end the Adventure Pass program that imposes recreation fees on visitors to Angeles National Forest and other federal lands.

Tamara Wilton, Recreation Fee Program Manager for the Forest Service in California, said that her office was continuing the fee program and waiting for developments and legal guidance before making any changes. She called the situation “frustrating.”

A three-judge panel of the U.S. Court of Appeals for the Ninth Circuit, ruling in an Arizona case, wrote in a unanimous opinion on Feb. 9 that the Forest Service cannot charge a fee for visitors who simply park, hike or picnic in a forest without using such amenities as toilets, picnic tables, trash containers and security services. The Ninth Circuit includes California as well as Arizona and seven other western states, Oregon, Washington, Montana, Idaho, Nevada, Hawaii and Alaska.

The appeals court in San Francisco remanded the case to the lower court in Arizona, where a government attorney said that as of mid-April, no further hearing had been scheduled on the matter.

Wilton said Adventure Pass fees totaled $1.237 million in Angeles National Forest in 2010, and $1.1 million in the San Bernardino National Forest. For all of California, the total that year was $7.1 million. Much of the money was used to maintain and improve facilities such as restrooms and trails, to finance visitor services, and for helping to fund partnerships with nonprofit organizations in forest projects.

Getting money to replace Adventure Pass fees would be difficult at a time of budget cutbacks. One potential source would be an estimated $2 million to $4 million annually for the region in National Park Service funds under a proposed National Recreation Area for Angeles National Forest and communities along the San Gabriel River to the south.

It is hard to see how the Adventure Pass can be structured to work if the appeals court’s ruling stands. The appeals court said that the “Forest Service’s fee structure contravenes the plain language” of the Federal Lands Recreation Enhancement Act (REA) enacted in 2004.

To charge a fee, the court said, the REA requires the recreation area to have all of these amenities: 1) designated developed parking; 2) a permanent toilet facility; 3) permanent trash receptacle; 4) interpretive sign, exhibit, or kiosk; 5) picnic tables; and 6) security services.

Campaign Seeks to Reduce Risky Climbs at Eaton Canyon Falls
May/June 2012

The hike to Eaton Canyon Falls is a rewarding stroll along a shaded stream with several boulder crossings to test balance and reflexes, birds and squirrels in the trees and an occasional duck in a calm pool, culminating in a 60-foot waterfall plunging into a pond framed by rugged hillsides.

Many of the estimated 480,000 visitors to Eaton Canyon each year do the trek, making the rocky trail to the falls one of the most popular in the region.

But for a few hikers it suddenly turns dangerous, even deadly. They try to climb the steep slopes near the falls, get stuck and fall trying to find a way down. Last year, emergency teams were called to Eaton Canyon 60 times to rescue stranded or injured hikers. Three were killed when they fell, two of them in one week last August. Both men were in their early twenties.

Hoping to change the picture, authorities have launched a campaign to make hikers more aware of the risks. At an April 17 press conference at the Eaton Canyon Nature Center, officials from several county and Pasadena fire, sheriff’s and parks and recreation agencies, along with the U.S. Forest Service, sounded similar themes: Enjoy the hike along the stream and the falls, but don’t risk your life trying to climb those steep, crumbling hills.

There is no trail on the fragile ridge and cliffs above the falls, they said. Climbers are all too likely to get stuck up there, perhaps suffer an injury, while feeling exhausted, overheated or worried about bees, scorpions or snakes. Of the 60 rescues last year, 35 were injured hikers, and 20 had to be flown out by helicopter.
All of this costs taxpayer money, and puts search and rescue teams at risk as they evacuate hikers using ropes and anchor points for safety.

Officials planned to spread the word with news releases, Facebook and other social media, and a short video on a DVD. And rangers will walk the trail occasionally.

And a sign as hikers leave the county park warns of the danger of climbing at the falls—a half mile or so ahead.

See past conservation articles in archived issues of Arroyo View:
Mar/Apr 2012
Jan/Feb 2012
Nov/Dec 2011

Conservation Resources
Center for Biological Diversity
League of Conservation Voters - Up-to-date headlines
Neighbors for Better Transportation - Issues surrounding the proposed extension of the 710 freeway
Sierra Club Website
The Nature Conservancy
Wild Wilderness - This web site is put up by Scott Silver, an authority on the subject of the Adventure Pass.

Pasadena /Western San Gabriel Valley
Arroyo Seco Foundation - Save Hahamongna Watershed
California Native Plant Society - San Gabriel Mountains Chapter
Eaton Canyon Nature Center - Site of the Pasadena Group monthly meetings
Friends of the Los Angeles River
Pasadena Audubon Society
Urbanwild Network - a coalition to protect urban wilderness