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Imagine you are just minding your own business, doing your Opuntia basilaris thing, feeling safe and protected by growing next to an Agave deserti, with its super-sharp spiny leaf tips. Then the Agave flowers, and suddenly, one day later, the whole plant falls over, spearing one of your pads, yanking it from the rest of the plant, and then lifting it high in the air.

In the last two pix, Don Rideout created the "before" scenario by restoring the Agave stalk to its upright position, which restored the base of the Opuntia pad to its former connection with the rest of its plant.

Some people might draw a "lesson" from this example. (;-)

The purpose of these observations is to record the fruit of Arctostaphylos glandulosa along this section of the Pacific Crest Trail. There are two subspecies of glandulosa here. We sampled several fruit to see if they are helpful in differentiating the two. Specifically, we looked at whether the stones (seeds) remain intact or separate into individual propagules.

This observation is plant #5. Some stones remained intact while others readily separated into several propagules.

Our original objective was to see this lily which was originally found by Paulette Donnelon. She called it a "monster lily" because it is so densely packed with buds. It turns out to be more than one stem, and most likely more than one bulb. As the stalk elongates it may become easier to see how many stems there are. Photo 6 was taken at 5:37 pm with the moon rising behind it.

I happened upon this shrub in a patch of intact sage scrub back in September while doing butterfly survey at the Bernard Field Station. At the time, I thought it was Brickellia nevinii, which had once been on our plant list but was removed because we could not confirm its presence.

I have been waiting for it to bloom and now it has. But looking at the flowers, I no longer think this is B. nevinii because the phyllaries don't have recurved tips (Jepson Brickellia key).

We had Brickellia californica elsewhere on site, and this shrub looks quite different. The foliage is much grayer, and the leaves are smaller. Also, the known B. californica bloomed in July, not November. Could this possibly be B. desertorum?

Adjacent vegetation consisted mostly Artemisia californica, but also included Eriodictyon trichocalyx, Cylindropuntia californica, Opuntia littoralis, and a couple of very large Rhus integrifolia. (You can also see a woodrat nest in the background.)

This tree was knocked or blown down one year ago. See:

https://www.inaturalist.org/observations/88736033

On this trip, I couldn't believe it wasn't dead! It has the thinnest possible connection left to its roots, yet it still manages to have a good amount of foliage, mostly on the side of the trunk that still has that tenuous contact with its roots.

Plants do make noises too. Perhaps not the proverbial growth of grass, but exploding seed capsules are part of the soundscape in the Santa Monica Mountains this time of the year. I noticed it first when I tried to locate a Wing-tapping Cicada and realized that the Vetches fooled me, https://www.inaturalist.org/observations/48232169.

Bigpod Ceanothus trees are even noisier than Vetches because they carry many more fruits per cubic meter. If you wait and listen close to one, you’ll be bombarded with seeds from the exploding, ripe fruits.

Wikipedia notes about the fruit of these trees: “The inside of the capsule is divided into 3 valves, each valve holding a seed. The capsule dehisces neatly in three at the central band to release the seeds.” And, “Dehiscence is the splitting, at maturity, along a built-in line of weakness in a plant structure in order to release its contents, and is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part. Structures that open in this way are said to be dehiscent. Structures that do not open in this way are called indehiscent, and rely on other mechanisms such as decay or predation to release the contents.”

Dehiscence doesn’t mean there’s necessarily a hiss. In this case it’s a sharp ticking sound. In the background of the recording are a Common Raven and a Northern Mockingbird.

To celebrate the quieter times, I petitioned @finatic, the creator of https://www.inaturalist.org/projects/audio-observations-from-around-the-world, to include maybe a few plants in his project that is animalia only.

A huge number of barrel cacti were eaten at the base in this area surrounding the lower part of the wash from Glorietta Canyon. There was a lot of rabbit poop surrounding at least some of them, implying that rabbits were the main predators here.

The stems got eaten more and more during my hike, so I ended up taking pix of six plants. The last ones in this series were completely girdled, yet the tops looked fine. The cacti were saved by having vascular tissue in the center of the barrel, instead of at the edges.

A huge number of barrel cacti were eaten at the base in this area surrounding the lower part of the wash from Glorietta Canyon. There was a lot of rabbit poop surrounding at least some of them, implying that rabbits were the main predators here.

The stems got eaten more and more during my hike, so I ended up taking pix of six plants. The last ones in this series were completely girdled, yet the tops looked fine. The cacti were saved by having vascular tissue in the center of the barrel, instead of at the edges.