Bicolor Everlasting

Several similar species of everlasting grow in the Reserve. Bicolor everlasting (Pseudognaphalium biolettii) can be recognized by its leaves, which are green above and pale below, by its white stems, and by its strong aroma, reminiscent of citrus mixed with another substance – somewhat like a lemon cleanser.

Everlastings are relatives of daisies and dandelions. Like them, what appears as one flower is actually a flower head, itself a cluster of minute flowers (called florets). Everlasting gets its name from the dry, papery scale-like phyllaries that surround the base of each flower head. These persist, resembling dried blossoms long after the true flowers have vanished.

Description ^4,26,59

Bicolor everlasting is a small, rounded perennial herb, usually less than three feet (1 m) high, with several branches from the base. Stems and leaves are covered with small glandular hairs that give them a sticky feeling and a characteristic aroma, usually described as “lemony”. To this writer, it resembles the odor of lemon cleanser. Plants go dormant during the summer drought and resprout with the winter rains.

The stems are made pale by long white hairs. Leaves range from oblong to oblanceolate or lanceolate, usually less than 2¾ inches (7 cm) long and ½ inch (0.6 cm) wide. Leaf edges are smooth, often wavy, with the margins partially rolled under. Leaves lack petioles; their bases clasp the stem directly, with two small collars at either side of the attachment point. The upper surface is a clear or grayish green; the lower surface is covered with white woolly hairs, making it distinctly paler. The contrast in leaf color gives the plant many of its common names (e.g. bicolor everlasting, two-color rabbit tobacco, two-tone everlasting). Jepson describes a form with low contrast between leaf top and bottom; this is less common in the Reserve (or less easily distinguished from other species).

Flower heads are born in flat-topped clusters, up to six inches (16 cm) across. Each cluster is composed of 5-18 flower heads, each flower head composed of 60 – 100 tightly packed disk florets, subtended and surrounded by an urn-shaped involucre with several series of lustrous white, papery, scale-like structures (phyllaries) that largely obscure the disk florets. The phyllaries persist on the flower head long after the florets have been lost, resembling straw-colored petals and giving the plant the common name of “everlasting”

Most florets are female, roughly 1/8 inch (0.3-0.4 cm) long. The tubular corolla is greenish or cream-colored with five yellow lobes. The calyx persists as the pappus of several whitish bristles about as long as the corolla. Stamens are absent from female flowers, and the pistil consists of a one-chambered, inferior ovary and a forked style with spreading or recurved branches that extend beyond the corolla. A few central florets are bisexual. These are similar to the female florets but about twice as broad. Bisexual florets have five stamens with yellow anthers that are fused into a cylinder around the forked style. The seeds are small and may be wind-dispersed with help from the pappus. Bicolor everlasting blooms between January and May.¹

Classification

Bicolor everlasting is a dicot angiosperm in the sunflower family, the Asteraceae.^2,11 This is one of the two largest families of vascular plants in the world, second only to the orchid family (Orchidaceae).^44,143 “Flowers” of the sunflower family are made up of one or both of two types of small flowers, called florets: symmetrical disk florets and strapped-shaped ray florets. These are crowded onto a common base (receptacle), and the whole is called a flower head, which is often assumed to be a single flower.^11,49  Although a few plants in this family, such as lettuce and artichokes, are used as food plants,  their main economic value comes from their use as ornamentals: sunflowers, daisies, zinnias, marigolds, chrysanthemums, and many more.¹⁴³ On the other hand, many plants in this family are serious agricultural pests.⁴¹

More than 75 species of Asteraceae have been reported from the Reserve.⁴⁸ Conspicuous species include bush sunflower (Encelia californica), goldenbush (Isocoma menziesii), and coyote brush (Baccharis pilularis).

Plants of the sunflower family are divided into tribes on the basis of flower and fruit morphology.^11,310 The everlasting tribe is one of the more easily recognized; it is distinguished by the lack of ray florets and by the papery phyllaries that surround the base of each flower head and largely conceal the disk florets.

There are six native species of everlasting in the genus Pseudognaphalium reported in the Reserve.⁴⁸ Bicolor everlasting and California everlasting (P. californicum) are the most commonly identified.

Ecology

So far as we can determine, bicolor everlasting has escaped the attention of ecologists. Nevertheless, one can’t help wondering why this little plant spends energy to produce such a strongly scented compound. Does the aroma have a direct benefit – either to attract or discourage certain organisms? Or is the odor an indirect consequence of another function? Perhaps the smelly compounds taste bad, discouraging herbivores, or perhaps it chemically inhibits competing plants (allelopathy).

This is all speculation. Teachers and docents, what do your students think?

Human Uses

Delphina Cuero recalls the Kumeyaay using  bicolor everlasting as a poultice for sores,¹⁶ but most ethnobotanical reports do not distinguish among the species of everlasting, which were made into a tea for relief from colds and stomach pains.^15,282

Modern herbal medicine suggests species of Pseudognaphalium  for sciatica that alternates with numbness.²¹³

Interesting Facts ^59,85

Bicolor everlasting and related species are hosts for the American lady (Vanessa virginiensis), a medium sized orange butterfly similar to the painted lady and the west coast lady. The dark, spiny caterpillar uses the bicolor everlasting for shelter, folding over the upper leaves and securing them into a cozy tent where it rests when not feeding.^53,59,389