White Sage

Compared with the other local sages, white sage (Salvia apiana), has larger, paler leaves and longer, taller stalks of flowers – an imposing plant with an imposing odor.

This sage is truly distinguished by the unusual flower structure. What may appear as the typical two-lipped sage flower, is actually the enlarged and frilled lower lip that folds back and out again, completely obscuring the small upper lip, and blocking the throat of the flower and the nectar source. Only a large insect, such as a carpenter bee or a bumble bee, is heavy enough to depress the lower lip of the petal and open the path to the nectar. Smaller pollinators may visit white sage but rarely do they obtain nectar or contact pollen. Thus, white sage has a private set of pollinators, and this appears to reduce hybridization with nearby sages of different species. This is acknowledged by the scientific species name, apiana, which means “bee”.

Description ^{4,11,23,24,59}

When not in bloom, white sage is a perennial, low-growing, rounded sub-shrub usually less than three feet in height. There are numerous basal branches with dense clusters of pale gray, slightly thickened leaves that have a smooth, almost rubbery feeling. Leaves are paired along the stem with petioles that wrap the stem. They are ovate to broadly lanceolate, tapered at the base, with an acute tip, generally 1½ – 4¾ inches (4-12 cm) long, and with a delicately scalloped margin. Leaves are covered with small white hairs, but these are very difficult to see without magnification. The entire plant, especially the flower clusters, is glandular and excretes a strong-smelling resinous substance that some find unpleasant. White sage often goes dormant during late summer.

Starting in late winter, stems begin elongating into long, straight, sparsely-leafed flower stalks that may reach six feet in height, making white sage our tallest local native sage. Unlike the stems of most sages, white sage stems are cylindrical. Unlike the flowers of most sages, flowers are not in discrete whirls but in small paired clusters along the top of the flowering stalk. The calyx is two-lipped. The calyx and flower stem are more or less tinged with red. Flowers are white, white dotted with lavender or pale lavender, strongly bilateral, about 1/3 inch (0.8 cm) across. The five petals are fused at the base, expanding outward into two lips. Two petals form a very small upper lip. Lower petals form a large, frilled, three-lobed lower lip, initially folded back over the upper lip before bending out and down. In a young flower, the folds of the lower petal close the throat; the folds relax with age. There are two long stamens extending at angles out and away from the flower. Stamens mature before the pistil. The pistil has a superior ovary, and one style with a forked, often purplish tip. The long style extends to the side of the flower. The major bloom time is April to July.¹

Each flower may produce up to four nutlets, which develop within the dry tube of the calyx. The tall, dry flower/seed stalks persist through the winter.

Classification ^43,44,59

White sage is a dicot angiosperm in the mint family (Lamiaceae). Members of this family often contain essential oils that give a strong scent, which may vary from pleasantly minty, to pungent and objectionable. Typically, stems are square in cross-section (white sage is an exception here), and leaves arranged in opposite pairs along the stem. Flowers are usually arranged in whirls; they are strongly bilateral, with both sepals and petals fused into two lips.  Many of our important culinary herbs belong to this family, including oregano, thyme, rosemary, basil, mint and lavender. There are no poisonous plants in the mint family.³⁴

The Salvia is the largest genus in the family and contains the true sages. Species in the genus are distinguished by details of flower structure, especially the staminal lever mechanism,⁴¹ which causes the stamens to pivot downward and deposit pollen on the backs of pollinators. Species often have flowers arranged in distinct whirls. Two other sages are found in the Reserve: Black sage (Salvia mellifera) and Cleveland sage (Salvia clevelandii).

Calflora⁷ currently lists one variety in California, S. apiana compacta, which grows at the edge of the desert. Our plants have no varietal designation but were previously designated variety apiana.

Ecology  

Although white sage seems to prefer hotter, dryer areas, the range of white sage overlaps with that of black sage so that they often grow together. The two species are able to cross-fertilize and produce viable young, but hybrids in the field are far less common than might be expected.^72,414

A part of the explanation may be that white sage and black sage have different pollinators.^{11,43,59,72,414} The complicated structure of a white sage flower serves to restrict nectar access to larger bees – those heavy enough to depress the lower lip and “open” the throat. As the lip is depressed and the insect collects the nectar, the long stamens pivot inward to deposit pollen on the back or side. Since stamens mature before the pistil, a pollen-dusted bee must approach another, more mature flower, before encountering a fertile pistil. The main pollinators of white sage are bumblebees and carpenter bees. Although honey bees are often attracted, and they may be able to reach the nectar, they appear to be ineffective pollinators because they are too small to be reached by the pivoting stamens. At the same time, the large pollinators of white sage are too large to access the nectar supply of the smaller black sage flowers. The two species are isolated by lack of common pollinators.

In the Reserve several years ago, a few hybrid plants were found along the Solana Hills access road. These had the large, pale leaves and tall flower spikes of white sage, but flower clusters were in distinct whirls and the flowers were intermediate in size and structure between white and black sage. At the present time, this area has been closed because of the freeway expansion. Because of the construction in that area, it is not certain that these hybrids will persist.

Human Uses ^{15,16,17,37,219,272,282}

Perhaps the best-known use of white sage by local Native Americans is the use of dried leaves in smudge sticks. Bundles of white sage leaves are dried thoroughly. The tip of the bundle is ignited and then blown out so the leaves continue to smolder, releasing a thick aromatic smoke. Inhaling this smoke, or letting it waft over the body promotes “spiritual harmony and balance”.¹⁵ Modern Kumeyaay often use smudge sticks in ceremonial contexts such as the opening of a community gathering.³⁷² Oddly, there is little mention of similar ceremonial uses in the past,^{15,16,17,272,282} suggesting that the practice is recent.

More traditional uses of white sage were medicinal, such as the use of a tea as an eyewash, and as a decongestant and treatment for colds and coughs. Like seeds of most sages, the tiny white sage seeds were eaten. White sage leaves were carried in the mouth or under the arms to disguise the human scent when hunting.

Interesting Facts ²²

White sage and black sage are hosts to the sage leaf gall midge (Rhopalomyla audibertiae), a tiny, two-winged insect related to flies. The sage leaf gall is a thick-walled, urn-shaped structure that develops on leaves and petioles. Gall are gray-green, occasionally reddish, less than ½ inch (1.3 cm) long, with an apical opening. Sometimes single galls grow together into larger masses. The gall offers protection and nutrition to the developing midge larvae which ultimately emerge from the opening as adults. Galls may also support a small community of midge competitors and predators.