Vascular Plants of Ladd Canyon's Journal

Ladd Canyon is an intriguing area of the Santa Ana Mountains to study. There are no official trails into the canyon. The old Ladd Canyon Spring Trail is no longer maintained, and the so-called Smashmouth on Pleasants Peak’s south ridge is an unofficial route following SCE power lines installed in the early 2000s. Most past botanizing has been along Main Divide, although there are some old records from the short Ladd Canyon Spring Trail in upper East Fork. Reason enough to get into the canyon to see what is there! But there is more to consider here. The area at the north of Ladd around Pleasants Peak has the only serpentine soil in the Santa Ana Mountains, and serpentine is an important source of endemic species in California. It has also been suggested that moist marine air is funneled by the local topography up through Ladd Canyon, increasing moisture levels. The knobcone pine stands near Pleasants Peak are said to be associated with the serpentine soil and to rely on fog drip from the wet marine air. Their needles really do collect an impressive amount of water in morning fog. Finally, the canyon has been largely untouched by fire since the Green River Fire in 1948.

These abiotic factors could make a difference in the plant community in this part of the mountains. This project is an effort to document all the vascular plant species in Ladd Canyon, and many of the iNat observations here are associated with voucher specimens that will be preserved at the herbarium at California State University, Long Beach.

Forgot to post this from the first week of June:

Months before I started the master’s program at CSULB and before I had a permit to collect in the national forest, I started looking for off-trail routes into Ladd Canyon, first by hiking up the Silverado Trail to Main Divide on the east, then by biking up Black Star and along Main Divide from the west. It’s an absolute joy to get into places few others have and see the grandest old trees and lilies upon lilies. But the bushwhacking is also the bane of my research. It just takes time, and I worry that I’m less observant when I’m tired out or simply looking for my way. This is why I tried to get a good jump on route finding before the collecting season began.

From the beginning, I have been concerned about the time it takes to get to the lower canyon from public access points. I got permission from CNF to backpack a couple of nights in the canyon for this reason. So it was a huge help when CNPS’s Ron Vanderhoff put me in touch with Scott Breeden and through him Susan and Anthony Mack, who have allowed me to access the lower canyon from Ladd Canyon Road. I can’t thank them all enough! On May 10 and 11, I backpacked with Mike McDermott and was able to explore halfway up West Fork. There’s a beautiful little falls up there, and a plant or two (perhaps most worth mentioning is a population of Monardella hypoleuca, 1B.3, also found in the main canyon). Having already backpacked down the main fork of the canyon and up East Fork, I felt like I had covered most of the area. All of which brings us to recent goings-on in Ladd Canyon.

When spring finally came, there was a bit of easy collecting in easy-to-get-to places. Perhaps there could have been a bit more, but yeah, it’s been pretty dry. In the last couple of weeks, I’ve poked around ravines and ridges along Main Divide, as well as the lower canyon riparian area. I was also thinking about how to get to the middle section of West Fork that I still hadn’t seen. Down and back from Main Divide would be a long day. I explored a ravine halfway down the south ridge of Pleasants Peak (the Smashmouth use trail following SCE power lines is on this ridge) hoping for a short route, but I was stopped by the largest dry fall I’ve seen in Ladd Canyon, probably 40 to 50 feet -- not sure because safety first! I didn’t get too close. This week, after looking at topos and satellite images, I decided I would head down West Fork from Main Divide and try going up a different ravine to Smashmouth. If it worked, I’d have a good day, and if it didn’t, I’d have a good, long day retracing my steps.

The middle section was beautiful, with some huge big-leaf maples and white alders, as well as some year-round pools with four big groups of horsetails, Equisetum telmateia. My route up to the ridgetop worked, but I can’t say that I’m eager to repeat it. It involved a scree slope (there’s been Phacelia imbricata on every scree slope I’ve scrambled -- love those shapely leaves), and some stubborn chamise and manzanita. I collected some Collinsia heterophylla -- not a rarity in the Santa Anas but a plant I hadn’t seen yet. It reminded me again to pray for rain next year. The going got easier when I reached the large stand of knobcone pines near the top. It was a steep 1,000 feet and getting late, so I had a little lie-down and the last of my water. My last observation of the day involved those pines. Vogl (1973) said the knobcones in the area were all associated with serpentine soil, but I had doubted that because it didn’t look to be the case along the Smashmouth trail. Climbing up through these trees, though, I came upon yet another outcrop of friable white rock with rusty red streaks that I think is serpentine-associated silica-carbonate. I still have to confirm that, but I feel guilty for ever doubting Vogl. Asking questions, though, that’s just science, right?

Soon to come: exploring the east fork of East Fork and revisiting summer bloomers in the mint and aster families.

June 4: I had a relatively short hike in lower Ladd Canyon, and I climbed a south-facing ridge. Everything was very dry on the ridge. It was pretty horrible for collecting, but I did find Bebbia juncea in flower, a new plant to me, and got a look at a new corner of the area. There are some small, permanent pools in the lower canyon, and I spotted some Western pond turtles again.

June 7: A much better day collecting. This hike started on Main Divide, headed down the east fork of East Fork Ladd Canyon, where I had never been, and ended up back on Main Divide on the north side of Bedford Peak by climbing a ravine. The sun only came out for maybe an hour all day. New collections included Madia gracilis, Rosa californica, and Allium peninsulara. Opening the newspaper on the rose at home perfumed my living room/botany lab. The onion has some of the prettiest flowers. Is that magenta? It's quite the color, anyway. The ravine where the onion was growing has some of the richest soil in the area. It drops to the northwest and is very shady. Dropping down the ravine halfway on an early exploration had turned up some woodland-star, Lithophragma affine. It's a neat spot. One regret for the day is that I thought I had collected Daucus pusillus in the area already and took only pictures, but it turns out I have never collected it. I always forget how bad my memory is.

June 16: I spent much of the day along Main Divide. Here's another story about learning by doing and making mistakes: One main goal was to collect some wavy-leafed soap plant, Chlorogalum pomeridianum, which I had noticed before and had been checking for blooms. When I checked June 7, there were lots of buds and some spent flowers, so I didn't collect it, figuring the buds would bloom and I'd have a better specimen. On this day, there were a few buds and lots of spent flowers, and I did collect it. Had a done a little research, I would have known that the plant is a night-bloomer! I should have made a plan to be around in the late afternoon/evening just after the buds open. I ended up dissecting some buds before pressing. I dropped down into the main fork of Ladd Canyon for a little bit, and found not too much in bloom. The Pycnanthemum californicum there was growing well but had no buds yet. The highlight of the day was the flower show in the area's largest Lepechinia cardiophylla population. There were plenty of pollinators, including Osmia bees and syrphid flies. Opening the field press at home was another sweet experience. I sat breathing in the minty smell for a good minute before getting to work. The day was extremely hot, upper 90s, and I never strayed too far from the truck's AC. In fact, when I was taking pollinator pictures at the end of the day, including some video, my phone had a heat stroke and shut down. I took it back to the truck and held it up to the vent as I blasted the AC, and it was able to return to life and take a few more shots. Sheesh.

June 21: A good day collecting in lower Ladd Canyon, with a good side trip up to a rock outcrop on the south side of the canyon. New collections for the checklist included several riparian plants: Erythranthe cardinalis (scarlet monkeyflower), Hoita macrostachya, Datisca glomerata, and Rumex conglomeratus. The Rumex (aka clustered dock) is a nonnative that doesn't seem to be terribly common in the mountains. Before turning around, I ventured south up a side canyon that seems relatively long and manageable, but I soon got distracted by a scree slope below a stone outcrop. It looked like an interesting change from riparian habitat, and it was. I had spotted some Weed's intermediate mariposa lily early in the day, a species of concern. There were only five plants, so I had no collection. Here, I found more than 45 plants among the scree and spikemoss. All the lilies are nice, and this batch made a pleasant scene. I made a few other collections here, including some Eriogonum fasciculatum (buckwheat) that was blooming like crazy. I haven't paid enough attention to it since it is super common, but I want to make sure to get all subspecies in the area. These seemed to be ssp. polifolium. I'll have to look more closely.