Plant Species of San Jacinto Mountain: Fragrant Plants


Fragrant Flowers
Fragrant Leaves
Fragrant Bark or Wood
Fragrant Roots


There are a small number of plants at San Jacinto that have such a lovely smell that we look forward to encountering them, and then delight in their fragrance. This page lists our favorites.

There are other plants with strong smells that are not pleasant, but are still of interest. For example, some scents can help to identify young plants not in bloom. This page lists those odiferous plants as well.

Interestingly, not everyone agrees on whether the smell of a particular plant is fragrant or odiferous! One example most people are familiar with is the smell of the cultivated Easter lily. Some people think it is a wonderful sweet smell; others can't stand it.

For that reason, and for convenience, we'll refer to both good and bad smells as fragrance on this page.

Almost all plants probably are fragrant to some degree, since each contains chemicals designed for numerous purposes, and many chemicals have a detectable odor. Some chemicals are simply part of the make-up of the plant; some attract insects for pollination; some repel insects who want to eat them; some are signals to neighboring plants; and some are even invitations to attract predators to consume insects eating the plant.

If our sense of smell was as good as that of a dog, we would probably be able to smell many more plants than we do. Dogs have such a great sense of smell that they have been trained to detect rare plants by smell, and they can distinguish some rare plants from their look-alike species better than most humans can do using our other senses.

It turns out that humans have essentially the same suite of odor-sensing genes as dogs do, but something like 85% of our odor-sensing genes no longer work due to mutations that have disabled those genes! Which genes still function can vary from person to person, so that some people find some plants intensely fragrant, yet some people cannot smell them at all! That is simply because that particular gene for that molecule still works in some people, but not in others.

One of the best examples of the variance in smell among people is from Phacelia ramosissima, our common branching phacelia. About half of the human population cannot smell its main scent at all, even though the other half find the scent very strong and almost nauseating. If you can't smell this nauseating chemical, count yourself lucky!

Another example from the plant world is cilantro. To most people, it is a delight to smell it, but to some people, it smells like soap.

Humans shouldn't feel bad about losing so much of our sense of smell, since it appears once primates developed color vision, that new sense was so much more powerful that it was no longer as important to have an acute sense of smell.

Plant fragrance can vary tremendously. The flowers of Rhododendron occidentale, western azalea, are so fragrant that both of us can sometimes detect a group of plants in bloom well before we can see them, often from 100 feet away or more. In contrast, some flowers, such as those of Sambucus nigra ssp. caerulea, blue elderberry, require you to push your nose in the group of flowers to detect a faint fragrance. Sometimes an individual flower has only a faint scent, but when there are masses of flowers, the scent is very strong, as for both Deinandra mohavensis, Mojave tarplant, and Penstemon grinnellii, Grinnell's beardtongue.

Flower fragrance can vary tremendously with bloom stage, and/or with the time of day. Plants pollinated by moths often put out their fragrance primarily at dusk, such as Piperia transversa, mountain piperia, or have their strongest fragrance at dusk when they first open, such as Lilium parryi, lemon lily. Flowers that have been pollinated, or older flowers, may cease to produce fragrance.

Plants can be fragrant in many different ways. We usually think of fragrance as coming from flowers, which often is the case, but scents can come from other plant parts, such as:

Onions, Allium sp., are noted for having all parts of the plant fragrant.

The following lists present the San Jacinto Mountain species for which we have personally detected fragrance, or, when our memories are weak for a given species, that are reported to be fragrant. The lists are incomplete, since we've just begun this page in November 2019.

Separate lists are given by where the fragrance comes from flowers, leaves, bark, or roots. Since the involucre is part of the flower head, albeit under the ray and/or disk flowers, those plants are included in the flower list. Within each list, species are presented in alphabetical order by scientific name.

For the flowers and leaves section, we also give a list of our "top four" species for strong, pleasing fragrance, ones we always look forward to smelling.

Fragrant Flowers

Our 'Top Four' species, in alphabetical order by scientific name: Ceanothus leucodermis, Lilium parryi, Philadelphus microphyllus, and Rhododendron occidentale. See their entries below for their common names and details about their fragrance.

Ceanothus species, California lilac. One of our Top Four species for fragrant flowers. As far as we know, all Ceanothus species have fragrant flowers, with at least two types of fragrance. C. leucodermis and C. palmeri have a strong sweet fragrance. We can always get a sweet smell by placing our noses next to the flowers, and sometimes, when there are fields in bloom at once, the entire air is perfumed for some distance. We don't recall C. cuneatus and C. perplexans having a similar strong pleasant fragrance, although they both are fragrant. However, we need to check on the fragrance of these two species to be sure of our recollections.

Chrysolepis sempervirens, chinquapin. These have strongly-scented flowers, that are quite malodorous in large quantities. Tom regularly gets almost nauseated in hiking through fields of chinquapin in full bloom.

Deinandra mohavensis, Mojave tarplant. Tarplants produce a fragrance from their leaves, involucres, and flowers. This particular species can actually be identified from its strong scent detectable from some distance! We think that scent derives primarily from the flowers, since we haven't noticed its fragrance before or after bloom.

Lathyrus vestitus, San Diego or wild sweetpea. Do not expect this to have the heady strong fragrance of the garden sweetpeas! They have only a mild fragrance when you put your nose up to the flowers. They have such a mild fragrance that we can't even remember detecting an odor from them in the field. We'll check the next time we see flowers.

Lessingia glandulifera var. glandulifera, sticky lessingia, valley lessingia, or vinegar weed. This smells even less like vinegar than the other vinegar weed, Trichostema lanceolatum. The fragrance comes from rubbing the phyllaries surrounding the flower head, and is a lovely pungent strong smell.

Lilium parryi, lemon lily. One of our Top Four species for fragrant flowers. Lemon lily flowers have a strong very-pleasant fragrance that is hard to describe, but which is not that of a lemon. The flowers can sometimes be smelled from simply standing next to them in their first few days. The fragrance is most intense when the flowers first bloom at dusk, and fades in older flowers.

Lupinus excubitus var. austromontanus, mountain grape-soda lupine. The scent for most of our plants is faint, a sweet smell detectable only by placing one's nose in the inflorescence. Only very occasionally do any of our plants have a stronger fragrant smell, and even less occasionally do they have a grape soda smell.

The wonderful, but misleading at times, common name for this plant was given to it in the 1980s or so by Tim Krantz, from some very-strong scented plants in the San Bernardino Mountains.

Tom has detected a strong grape-sode odor, almost exactly like opening a can of grape soda under your nose, detectable from almost a block away from a good stand of plants in bloom in the San Gabriel Mountains. However, only about half the plants in the San Gabriel Mountains have that strong grape-soda odor; the other half are like the vast majority of our San Jacinto Mountain plant and lack that strong grape-soda fragrance.

Marah macrocarpa, wild-cucumber. Most of the time we do not detect any fragrance at all from its flowers. However, at dusk, a plant in full bloom sometimes has a very strong sweet fragrance, detectable from ten feet away.

Madia gracilis, slender madia. The phyllaries surrounding the flower head produce a somewhat-faint sweet smell when rubbed.

Penstemon grinnellii var. grinnellii, Grinnell's beardtongue. Most of the time the flowers have a very faint fragrance, detectable only by placing your nose almost inside the flower (watch out for bumblebees!). However, when a field is in full bloom, and there are masses of flowers, the scent is very strong, and can be detected just by walking beside the field.

Philadelphus microphyllus, little-leaf mock orange. This is one of our Top Four species for fragrant flowers. Just like the garden mock orange species, the flowers have a heavenly scent! If there are only a few flowers, you need to put your nose close to a flower to get a strong whiff. But if there are lots of flowers, it is a easy to smell them from some distance.

We discovered an interesting feature of their scent while picking a lunch spot near Cornell Peak one time. We had just found a patch with a large number of blooms, so we thought it would be wonderful to lunch near the plants. We moved over to a good lunch spot, and the odor became that of sewage! It took us a moment to realize the odor was coming from the very same flowers that smelled so nice up close. Fragrances are often due to several different chemicals, and some of the chemicals travel farther from the plant than others.

Piperia transversa, mountain piperia. Because these plants generally have a short inflorescence with small flowers, and have their strongest fragrance at dusk, most people do not realize how incredibly fragrant it is at dusk. (Actually, most people never even notice the flower stalks, and walk right past them.) The fragrance is distinctly clove-like.

Tom only found out what a strong scent it has when he took home a stem from the Ernie Maxwell Trail that he found lying detached on the side of the trail. Tom put it in water to see what flowers would emerge. At dusk, the entire room was filled with a very pleasant clove-like fragrance! The fragrance was much less the next day, but became strong again the next night.

Piperia elongata, dense-flowered rein orchid. We have not smelled this flower at dusk. The Flora of North America reports fragrance when present nocturnal, faint, harsh to honeylike.

Platanthera dilatata var. leucostachys, white bog orchid. We have not smelled this flower at dusk. The Flora of North America reports: An intense clove scent distinguishes Platanthera dilatata from related species across most of its range, but in the far northwest a more complex blend of spicy fragrances predominates..

Rhododendron occidentale, western azalea. This is one of our Top Four species for fragrant flowers. The flowers are so fragrant that both of us can sometimes detect a group of plants in bloom well before we can see them, often from 100 feet away or more. Often when hiking the Devils Slide at full bloom of this species we'll detect the lovely fragrance, and then have to look hard down below the trail to find the plants in bloom some distance away.

Rosa californica, wild rose. Fragrance similar to garden roses, requiring an up-close visit by your nose to smell them. Less pronounced than fragrant garden roses, but more pronounced than many garden roses which have very little scent.

Sambucus nigra ssp. caerulea, blue elderberry. The fragrance is faint enough that it also requires an up-close visit by your nose to smell them.

Fragrant Leaves

Our 'Top Four' genera / species, in alphabetical order by scientific name: Monardella species, Salvia pachyphylla, Stachys species, and Trichostema species. See their entries below for their common names and details about their fragrance.

Page not finished below this point; only list of names given.

Abies concolor
Allium burlewii
Allium campanulatum
Allium cratericola
Allium marvinii
Allium monticola
Allium parryi
Allium peninsulare var. peninsulare
Allophyllum glutinosum
Artemisia douglasiana.  According to Jim Adams they are considered a spirit plant by the Chumash and induce pleasant dreams.
Artemisia ludoviciana
Artemisia ludoviciana ssp. albula
Artemisia ludoviciana ssp. incompta
Artemisia ludoviciana ssp. ludoviciana
Artemisia tridentata 
Brickellia californica
Calocedrus decurrens
Chenopodium species
Corethrogyne filaginifolia
Croton setiger
Datura wrightii
Ericameria species
Mentha spicata

Mimulus fremontii var. fremontii, Fremont's monkeyflower. Harvey Monroe Hall, in his 1902 Flora, called this "a beautiful but malodorous little" plant, and we can confirm that! If you are confused about how to distinguish this species by other means, just rub a leaf and smell it. Shreveport says "foliage with a strong mephitic (=foul-smelling; noxious) odor".

Monardella australis ssp. australis
Monardella breweri ssp. lanceolata
Monardella linoides ssp. linoides
Monardella macrantha ssp. hallii
Monardella nana
Phacelia ramosissima
Pseudognaphalium beneolens
Pseudognaphalium biolettii
Pseudognaphalium californicum
Pseudognaphalium luteoalbum
Pseudognaphalium microcephalum
Pseudognaphalium stramineum
Pseudognaphalium thermale
Salvia pachyphylla
Scutellaria bolanderi ssp. austromontana
Scutellaria siphocampyloides
Stachys ajugoides one of our Top Four genera / species for fragrant leaves
Stachys rigida  Top Four genera / species for fragrant leaves
Stachys rigida var. quercetorum   Top Four genera / species for fragrant leaves

Tanacetum parthenium
Tauschia parishii
Trichostema austromontanum ssp. austromontanum  Top Four genera / species for fragrant leaves
Trichostema austromontanum ssp. compactum  Top Four genera / species for fragrant leaves
Trichostema parishii  Top Four genera / species for fragrant leaves

Fragrant Bark or Wood

Calocedrus decurrens

Pinus jeffreyi, Jeffrey pine. The bark crevices often have a sweet smell described as vanilla, pineapple, banana, and/or butterscotch. The odor is not apparent during low-moisture times of year, or on cold days, or on the shaded part of the trunk. Under most decent conditions, about 70% of the time, if you smell the bark of a Jeffrey, you'll get an odor of vanilla, etc., and ~30% of the time you'll get very little odor. Sometimes, the scent is so strong that it can be smelled just by walking past a grove of Jeffrey pines.

Pinus ponderosa var. pacifica, ponderosa pine. The bark crevices often have a non-sweet smell (turpentine odor), or a sweet smell not described as {pineapple or banana or butterscotch}, but possibly described as vanilla. The odor is not apparent during low-moisture times of year, or on cold days, or on the shaded part of the trunk. About 90% of the time, if you smell the bark of a ponderosa, you'll get a turpentine smell, or no smell, and ~10% of the time you may get a faint sweet smell that might remind you of vanilla, etc.

Fragrant Roots

Lewisia rediviva var. minor??

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Copyright © 2019 by Dave Stith and Tom Chester.
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Comments and feedback: Tom Chester
Updated 27 December 2019.