Category Archives: ahmanson ranch

Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch) After the 2025 Kenneth Fire

Ahmanson Ranch after the 2025 Kenneth Fire

The Kenneth Fire started at about 2:30 PM on January 9, 2025, near the Victory Trailhead of Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch). The Los Angeles Fire Department issued an alert about the Kenneth Fire at 2:39 PM.

According to the CAL FIRE Kenneth Fire Incident Page, the fire burned 1,052 acres, and was contained on January 12, 2025. The Kenneth Fire is the third significant fire to affect this area in the last 20 years — the other two being the 2005 Topanga Fire and 2018 Woolsey Fire.

At about the time the fire started, a personal weather station near the Victory Trailhead recorded the wind from the ENE at about 11 mph, gusting to 22 mph. At this station, the wind moderated somewhat over the course of the afternoon and early evening, but picked back up overnight.

The vegetation within the burn area is oak savanna — a plant community characterized by grassland and scattered oaks. In the case of Ahmanson Ranch the oaks are valley oaks and coast live oaks. The last known blue oak in the Preserve died in the Winter of 2022-23.

Taking into account their respective populations, the percentage of valley oaks destroyed by the Kenneth Fire far exceeded the percentage of coast live oaks. As the climate has warmed, the mortality rate of valley oaks in the southern part of their range has been increasing and their range retreating northward.

Although the wind was not as strong as it was on January 7-8, it was exceptionally dry. Prior to January 2025, Downtown Los Angeles only recorded 0.16 inch or rain for the Rain Year starting July 1 and  Water Year beginning October 1. As of January 9, the period July 1, 2024 to January 9, 2025 was tied with 1962-63 as the driest on record.

Here are some photos and notes from recent runs in Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch) following the 2025 Kenneth Fire.

Some related posts:
2025 Kenneth Fire Perimeter and Some Area Trails
Very Dry Start to the Downtown Los Angeles 2024-2025 Rain Year
After the Woolsey Fire: Ahmanson Ranch
The Topanga Fire, Part I: Rain, Wind and Fire

Mountain Lion Tracks in Upper Las Virgenes Canyon

Mountain lion tracks on the fire road in upper Las Virgenes Canyon, January 28, 2025.

While doing a run from the Victory Trailhead of Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch) yesterday, I came across the tracks of mountain lion headed (north) up the fire road in Las Virgenes Canyon.

The tracks were on the smaller side for a mountain lion, and probably those of a female or adolescent.

Some related posts:
It’s Raining Mountain Lion Tracks!
Mountain Lion Tracks on Rocky Peak Road
Mountain Lion Saga

2025 Kenneth Fire Perimeter and Some Area Trails

2025 Kenneth Fire Perimeter and Some Area Trails

The information in this post may be incorrect or out of date. For official information, see the Kenneth Fire incident page on the CAL FIRE website. The perimeter is from the Wildland Fire Interagency Geospatial Services (WFIGS) Group and National Interagency Fire Center (NIFC) website. The perimeter shown has a poly_DateCurrent of 1/11/2025 1:34:57 AM UTC.

The Kenneth Fire started Thursday afternoon, January 9, 2025, near the Victory Trailhead of Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch).

Here’s an interactive, 3D terrain view of the 2025 Kenneth Fire perimeter along with GPS tracks of some of the trails in the area.

According to an MRCA post on Instagram, Upper Las Virgenes Canyon Open Space Preserve reopened on Saturday, January 25, 2025.

Very Dry Start to the Downtown Los Angeles 2024-2025 Rain Year

Blooming brittlebush (Encelia farinosa) on the southwest corner of Lasky Mesa at Ahmanson Ranch on December 24, 2024.

The last time Downtown Los Angeles had more than a smattering of rain was mid-April 2024 — more than 250 days ago. To date, the Rain Year beginning July 1, 2024 has been one of the two driest in the 147+ year weather record for Downtown Los Angeles.

Because of the time of year, and lack of rain, not many wildflowers were blooming along Los Angeles area trails at the end of 2024. One exception was this brittlebush (Encelia farinosa) on the southwest corner of Lasky Mesa in Ahmanson Ranch.

If Los Angeles doesn’t see any rain by January 9 — which appears likely — the period July 1, 2024 to January 9, 2025 will be tied with 1962-63 for the driest on record.

Tarantula on Lasky Mesa

Tarantula on Lasky Mesa

It’s always a treat to see a tarantula ambling along a road or trail.

In Upper Las Virgenes Canyon Open Space Preserve (Ahmanson Ranch) the most likely time to see a tarantula is in September or October.

They are generally not aggressive, but can move very quickly if needed.

Some related posts:
September & October are Tarantula Months!
Tarantula Time