Tag Archives: rare plants

survey season

This spring I’ve helped out with a couple plant surveys organized by the local CNPS chapter. There are plenty of plants in the county and relatively few people to survey them, so the chapter picks a plant or group of plants for which there’s a compelling need to inventory them. The theme this year was dune plants. I don’t know this group of plants very well, so it’s been a great learning experience.

Surveys in two locations netted five or six rare List 1B species. (See the CNPS definition of the various listings [ here ].) I was there for four to five of them.

At the first location it was hard to miss the rare form of Juncus acutus, towering over my head. Shown here, it’s surrounded by the common but wonderfully perky yellow beach evening primrose (Camissonia cheiranthifolia) and the exotic sea rocket, Cakile maritima.

(A closeup of the dune evening primrose.)

Also nearby, also yellow, common, and perky: telegraph weed, Heteroteca grandiflora.

But enough of these common plants. We came here looking for rare ones!

Here’s one that was pretty hard to miss: Nuttall’s lotus, Lotus nuttallianus. I hope you like yellow. The bright flowers turn orange-red after they’ve been pollinated, encouraging the pollinators to visit the still-not-deflowered yellow blooms.

This snowy plover and least tern preserve was one of the plants’ favored areas. The word “preserve” promised more than was evident here. It was a patch of sand like any other part of the beach, but with just one piece of white string around it. Any dog or small child or group of teens with a cooler could have stepped inside, squashing the plants, scrambling the eggs and nestlings.

We saw several hundred of these, Brand’s phacelia, Phacelia stellaris. Around the edges of this patch you can see the one of invasive species of Erodium.

Another look at the phacelia… Most were about this size, practically belly flowers. But occasionally–as in the semi-shade beneath a picnic bench–you’d find individuals almost a foot tall.

And the last of the rare plants we surveyed the first day, coast wooly-heads, Nemacaulis denudata var. denudata. There were thousands at the first site. They weren’t flowering yet, but the plants were unmistakable with their long accordion-pleated white leaves. In bloom, they’ll have wiry stems floating little creamy balls of bloom over the leaves.

Here’s a final shot, a closeup of the flowering heads of the Juncus acutus. ssp. leopoldii.

It’s a stunning plant out on the sand. And of all of these, the common form of Juncus acutus is something you’ll see offered in various native plant catalogs. If you need a big, architectural, spiky sedge that likes a certain amount of moisture, this might be just your plant.

21,015 tiny little plants

I now have a new appreciation for the work of field botanists.

A couple weekends ago I had a chance to work on a rare plant survey on the slopes of Viejas Mountain in eastern San Diego County. I enjoy seeing plants out in their wild habitat and the description of the task sounded downright idyllic: You go out to trailless edges of the county, enjoy the scenery, and all the while look for rare plants.

San Diego thornmint (Photo: Janet Franklin)

The plant of special interest for this trip was San Diego thornmint, Acanthomintha ilicifolia, a plant found only in a smattering of places in California and bits of northern Baja. And the plant is even more selective than that. It only grows on clay lenses–gently or moderately sloped areas of clay soil that has washed down from nearby areas. The surrounding chaparral plants for the most part don’t care for these soil conditions, so they create openings for this rare annual to colonize.

The project was to get a population count of thornmint from areas where they’d been sighted more than a decade earlier. Comparing today’s numbers against the earlier censuses would give you an idea of how well the plant is doing in the wilds.

Me, looking for thornmint, enjoying the scenery around my feet. (Photo: Janet Franklin)

Our assignment was population 51, a cluster of adjacent stands on the western edge of Cleveland National Forest, just outside the city of Alpine. (Looking back on the suburban sprawl I thought it looked a little like the photos of Area 51 taken from Freedom Ridge.)

Most of the spread had burned in one of the recent major wildfires to go through the county and was in the state of growing back—pretty successfully, since travel got to be tough some of the day. Whenever the chaparral parted and the soil conditions looked right, you scoured the ground for thornmints, which at this point in their lifecycle were mostly 1-4 inches tall, with most of them not yet in bloom.

No thornimint at this one sub-location, but lots of Palmer's grappling hook, Harpagonella palmeri, one of the species that's commonly associated with thornmint. (Photo: Janet Franklin)

One of the three sub-populations we looked at was completely gone. Nada. Zero plants. Maybe the fire wiped them out. Maybe we weren’t observant enough, though we fine-tooth combed the hillside.

Success--thornmints! (Photo: Janet Franklin)

But the other two populations gave us an exercise in counting plants. Lots and lots of plants. Tiny, tiny little plants.

By the middle of the afternoon we had a count, 21,015 plants. It was six hours of open slopes with no shade spent in deep concentration looking for the little plants, counting all the while.

I’ll confess: We did a little estimating when the populations got really large, and so we didn’t actually physically count all 21,015 plants. But 21,015 seemed like a solid estimate.

While it’s good to know that there are more than a handful of plants left in the wild, it’s also a little unnerving to see that they have such a limited distribution, and more disturbing that one of the three populations from earlier seemed to have vanished.

Locally common, but in the grand scheme of things, awfully rare, especially with human encroachment from Area 51 next door.

Hesperoyucca whippleii, one of the stunning garden subjects shown here in the wilds, with thronmint nearby. (Photo: Janet Franklin)

San Diego thornmint probably won’t turn into one of the great garden plants for California native gardens. But along the way we saw plenty of species closely related to those used in home native landscapes: laurel sumac (Malosma laurina), ceanothus (tomentosus and foliosus), stinging lupine (Lupinus hirsutisimmus), manzanita (one of the Arctostaphylos glandulosa subspecies)…

Blue-eyed grass (Sisyrinchium bellum) growing on a clay lens. (Photo: Janet Franklin)

…and one of my favorite flowering natives: blue-eyed grass, growing and blooming among the tiny little thornmints.

Usually my camera is the first thing I pack for one of these outings, but somehow I forgot it at home this time. My thanks to team-leader Janet for the use of her images from the trip!

world’s thorniest rose?

I grew this fiercely thorny rose, Rosa minutifolia, for over a decade. With wild-rose-pink flowers barely two inches across, its petals were crinkled and delicate, but the blooms were never particularly stunning when compared to the buxom, botoxed blooms of typical garden roses. The leaves were tiny to the point of almost being non-existent, and I’ve already mentioned the incredible number of thorns that made this just about the prickliest thing I’ve ever dealt with. (The only similarly thorny roses I can think of are a few heirloom moss roses like Alfred de Dalmas that I grew in my early teen rose-growing years.) So spiny is it that one of its early collectors proposed an alternate name for it: Rosa horrida. (Check out the fascinating tale of its discovery by Barbara Ertter here.)

In the end, I think I grew it partly because of its weirdly cool thorniness and its interesting story, but also because of its artificial, political rarity. In the United States, this rose is found only as a small island population along the Mexican border on Otay Mesa, here in San Diego County. This extreme rarity has placed it on California’s endangered species list. Skip south into Mexico a few dozen miles, however, and the plant begins to become a fairly common member of the chaparral plant community, forming great mounded thickets three to four feet high and many feet across. The notion that the plant is particularly rare is an artifact of national boundaries. Erase the US-Mexico border, and Rosa minutifolia becomes a mainstay of part of the pan-Californian ecosystem.

I find that to be a weird little mental game: Is the plant rare or not? What odd things do political boundaries do to how we understand the natural world that those boundaries are drawn over? Does that mean that it’s crazy to call this an endangered plant?

To that last question, I’ll answer that we really should consider it a plant to protect. We need to preserve what’s left of the diversity that remains in the world. If the plant goes extinct in California, it’s gone from California. Never mind that it has cousins south of the border.

Borderlands, Continental Divide produced by The Cornell Lab of Ornithology from iLCP on Vimeo.

And these days the purely conceptual notion of a national border is turning into a physical reality, as the ginormous border fence project turns the United States into a freakish zoo exhibit behind bars as this video produced by the Cornell Lab of Ornithology shows. (I also did a brief post related to all this recently, on the destruction of Smuggler’s Gulch.) When the only know U.S. population of this plant is further isolated from its southern kin, it becomes all the more desperate to preserve what little we have left.

When we were preparing the back yard for a small room addition we needed to move a few plants out of the way. My Rosa minutifolia was one of them. Used to near-desert conditions, the plant shoots down roots far into the ground, maybe even 20 feet deep. I guess I didn’t get enough of the roots, not to mention the fact that the transplant took place in the high heat of summer. The plant declined and then died over the course of a couple months.

I see the plant here and there. A native plant sale might have a few plants. The Tree of Life Nursery stocks it. Botanical gardens sometimes have a little thicket of it (or a massive thicket of it as is the case at Rancho Santa Ana Botanical Garden where “five rooted cuttings planted…in 1954 had become ‘one large tangled mass’ nearly 30 feet across by 1982” [ source ]). All these photos are from the Huntington’s Desert Garden, where the rose grows alongside cactus and other things that make its spininess look right at home.

I get nostalgic whenever I see it. My little plant, which was set in awful, dense, dry soil in a much too shady spot, never grew or flowered much. Nipping at the dead branches kept it from forming a Rosa horrida thicket. But I continued to coddle it for whatever reasons any of us coddle interesting, under-performing plants. And one of these days I wouldn’t be surprised if I plant another little thicket of it.