Astragalus ertterae

Walker pass milkvetch

Fabaceae

There are plants in the Mojave that have very wide distribution, and there are some that have extremely limited ones. One of the later, in fact, one of the most extreme cases, is the Walker Pass Milkvetch, a member of the pea family. The entire known, and confirmed population of this plant is limited to a handful of individuals located on one section of the Pacific Crest Trailnorth of Walker Pass. The original site records only showed 1 plant, but in recent years, there has been some recruitment, and now the population has exploded to 14 plants.

This extreme endemism is an example of how limited in distribution a plant species can be. And the fact that the entire population is located directly adjacent to a regularly traversed hiking trail may seem like a concern. However, the obscurity of the plant is its shield in this case. Yes, there may only be 14 of them, but most people are walking the PCT are not climbing the banks, which is where the plant grows. Still, like all rare plants, there is some degree of danger to it, since it has such a limited known distribution. In all likelihood, there are other populations, which have, thus far, not been identified.

Special status species

In the Mojave, we are blessed/cursed with a large number of plant species, a significant number of which are rare or special status. This means that when we at the BLM are working on implementation of various projects, we have to look very carefully at where the proposals are located.

Special status plants are not uniformly rare, but are all protected by our policy. Some of our species, such as Cymopteris deserticola, the desert cymopteris, have a relatively large population. However, this doesn't mean that they are not rare, because they are only found in very specific habitats, and very few locations. This is like having an island which is the only location you can find the species, yet it is very abundant there. If you bulldoze the island to make houses, you have eliminated the only place that the species is found. So even though it was abundant, you've completely wiped it out. Or consider that with many of these plants, you can actually get a relatively accurate count of how many plants there are in the entire population. Try doing that with something like Larea tridentata, and you come to realize that there is a big difference between the two.

Seeds of Success

There are several projects that I've worked on for the BLM. The one I'm on now is called Seeds of Success. A part of the international seed banking program, SOS has a two-fold goal. The first is long term storage of seeds at the Millennium Seedbank in Kew England. The other is propagation for domestic use through the Bend Seed Extractory in Oregon.

I've found the project itself to be a mixed experience. On one hand, its an interesting task, finding species for the program and going through the process of collecting. I also deeply enjoy spending time in the field, and doing the collections themselves. Yet, the program is not flawless. There are parts of the protocol that are hard to apply to the desert region. One is the size of the population that the seeds are collected from. In many cases, there aren't enough plants to make a proper collection. Other times, there aren't enough seeds to meet the minimum of 10,000 while only taking 20% of the total seed volume. There are other difficulties, but those are two of the most prominent.

Platystemon californicus

Cream Cups - Platystemon californicus

Papaveraceae

A member of the poppy family, cream cups are a wide spread species, found from California all the way up into Oregon, east into Arizona, and south to Baja California. Phenotypicaly diverse, this species can be short and ground hugging, to tall and showy. Petal color can vary as well, from pure white to creamy-yellow. The flower stems, leaves and sepals of these plants are often very hairy, giving them a white, furry look.

These plants are popular in the horticultural scene, often used as a landscaping plant.

Salvia carduacea

Thistle sage - Salvia carduacea

Lamiaceae

Found in the lowlands of the Mojave, this member of the mint family eared its common name through its superficial resemblance to true thistles, members of the sunflower family. The flowers of this plant are typically mint, and are quite showy. This annual species can grow up to a meter tall in the right conditions, but those I've encountered are typically only half that size at most.

One of the most striking aspects of the blossoms are the feathered appearance of the lower lip, and the orange color of the anthers.

Salazaria mexicana

Paper bag bush - Salazaria mexicana

Lamiaceae

Of the Mojave's mints, one of the most visually unique is the Salazaria mexicana, commonly known as paper-bag bush. Twiggy, grey-green and somewhat thorny, this plant is easily recognized out in the field. Its most defining character, and in fact its namesake, is the small paper-bags that form from the plant's sepals during and after flowering. While the plant is in flower, the bags are warm pink, and subtend the flowers, while after flowering is complete, they dry and form a tough, papery "capsule" around the developing nutlets. When the bags eventually fall off, they are blown along the ground by the wind, dispersing them and the seeds.

These plants are typically found in exposed areas and drainages, typically where the plant's sepal-bags can catch and germinate. The plants themselves can become a medium to large bush.

Rafinesquia neomexicana

Chicory - Rafinesquia neomexicana

Asteraceae

One among the nearly 170 species of Asteraceae found in the Mojave desert, chicory is part of the dandelion group, having a resinous sap, no disk flowers, and plumose pappus. This annual plant is often found tangled in the branches of other, perennial plants, which it uses as a support structure in a inquilisticly commensal relationship. This relationship is not obligatory, and chicory can grow independent of a host plant.

The flowers appear in February, and typically persist until May. I often observed small beetles on the flowers, which could be the pollinator, or an opportunist feeding on the flower parts. The seeds are, like most Asteraceae, probably wind dispersed.