San Diego Natural History Museum Botany Department

Observations of the Month: Coville’s and Cleveland’s Lip Ferns (Pteridaceae) Coville’s Lip Fern (Myriopteris covillei) https://www.inaturalist.org/observations/37466571 by acorncap Cleveland’s Lip Fern (Myriopteris clevelandii) https://www.inaturalist.org/observations/71342268 by chloe_and_trevor Ferns are primitive plants. So you might think that you don’t need to take as many photos of a fern as you do of a flowering plant to capture important identifying characteristics.... But that’s not usually the case. Ideally, when you create an observation for iNaturalist, you would take 4 or 5 photos of a fern, just as you would of a flowering plant. With no flowers or fruits to focus on, you may be wondering what parts of a fern you should photograph. Take a photo of the fern as a whole to show its habit (growth form and general appearance). A photo of the upper surface of a leaf (blade or frond) showing its overall shape and arrangement and shape of leaflets (segments) and presence or absence of hairs or other structures. A photo of the lower surface of a leaf to show the color of the lower surface (it’s helpful to have the upper surface of an adjacent leaf in the same photo to give contrast). A second photo of the lower surface as close-up as needed to clearly show the structures found there (e.g., sori, hairs, scales). Be sure to have a finger, ruler, or other object in at least one photo to show scale. Coville’s Lip Fern and Cleveland’s Lip Fern look similar from a distance. With only one photo taken at a distance, it will likely be impossible to decide which of these species is represented. The location in our county can help since there is only a little overlap in the distributional range. Cleveland’s is found closer to the coast and inland up into the mountains where Coville’s is also found. Coville’s continues down the eastern slopes of the mountains and into some parts of our desert. Both species are often found growing in rocky areas. The upper surfaces of the fronds in both species are green and have no hairs although often the scales from the underside are readily visible on the upper side especially in Coville’s. Both have scales on the underside, but a close-up view of the scales will make all the difference in helping to determine which species it is. The scales on the underside of Coville’s are wider, obscure the surface, and exceed the margins. The scales on the underside of Cleveland’s are not as wide or as dense and are less likely to exceed the margins. By the way, if you look for the sori on the underside of a Myriopteris fern blade as I did and can’t find any, it’s because they are usually hidden under the recurved margins in this genus. Taking multiple photos of ferns to show different characteristics will make it more likely that the species in your iNat observation can be determined. Visit http://www.sdplantatlas.org/ for resources to help you identify ferns and other plants. See more

Observations of the Month: Stinging Nettles (Urticaceae) Dwarf Nettle (Urtica urens) https://www.inaturalist.org/observations/70230358 by andyjones1... Hoary Nettle (Urtica dioica ssp. holosericea) https://www.inaturalist.org/observations/54278783 by docprt Western Nettle (Hesperocnide tenella) https://www.inaturalist.org/observations/42434757 by kmerrill The plants featured this month are armed with specialized hairs filled with an irritating chemical solution which can be injected into the skin of unsuspecting observers who touch the stems or leaves. This group of plants have opposite leaves that are toothed. Their flowers are not showy: they have no petals and are small. All three plants prefer moist soils and can be found in much of the county, excluding the desert. Despite their similarities, you can tell these nettles apart by several characteristics. Unlike the other two, Dwarf Nettle is an introduced species from Europe. It is an annual which is often found in disturbed areas, parks, and gardens, and grows only to about 2 feet in height. Dwarf Nettle has clustered flowers arising from leaf axils, projecting only a short distance away from the stem (usually less than the length of the leaf’s petiole) which may appear as early as January until about April. It is the most common of the three and can be found from the coast inland to an elevation of about 3,200 feet. Hoary Nettle is a native perennial found in moist meadows and along the edges of streams, lakes, and other waterways. In addition to its stinging hairs, Hoary Nettle may have dense soft non-stinging hairs on its stems and the underside of leaves. It is a much larger plant than the other two nettles, growing from about 3 to 10 feet tall. Its leaves are larger and often folded along the midvein. The flowers of Hoary Nettle are more loosely arranged as a spike or panicle, extending from the stem often as far as the leaf tips, and are usually present from about June to September. Although it can be found in coastal San Diego, Hoary Nettle is more common in our mountains, and is the only one of the three to regularly occur above 3,500 feet. Western Nettle is the least common of the three and perhaps the most distinctive, with stems that are often red and leaves that are adorned with black dots at the base of the stinging hairs and rounded teeth. Its flowers are arranged in spherical clusters close to the stem and are present from about February to June. This native annual is the smallest of the three, growing to about 18 inches tall. It is often found in shaded areas, such as at the base of rocks or shrubs. It is found from the coast to the foothills, including at elevations somewhat higher than Dwarf Nettle, but not as high as Hoary Nettle. Be sure to visit the San Diego County Plant Atlas website (www.sdplantatlas.org) to find additional resources to help you identify the Stinging Nettles and other plants.

Our SDNHM Curator of Botany, Dr. Jon Rebman, is giving a general talk tomorrow for the Cactus & Succulent Society of America entitled "Baja California: botanical research and succulent diversity" that is open to the public. Feel free to join if you have the time and interest in this topic!

The man, the myth, the botanical legend. You hear from him all the time and this week we celebrate his 25th anniversary at The Nat. Hop over to San Diego Natural History Museum at noon for a special live stream with Curator of Botany Jon Rebman.

Tree Tobacco (Nicotiana glauca) Potato/Nighshade Family (Solanaceae) Family info: Solanaceae: The family Solanaceae includes approximately 75 genera and 3000 species with a worldwide distribution, especially diverse in tropical regions of South America. Members of the Solanaceae are herbs, shrubs, trees, or vines with usually alternate, simple or compound leaves, and typically small, whitish flowers arranged in a panicle that produce a capsule or drupe. The family contains ma...ny economically important members, including edible species such as peppers (Capsicum), tomatoes (Lycopersicon), and potatoes (Solanum); species with drugs like tobacco (Nicotiana) with nicotine or Belladonna (Atropa belladonna) with atropine; and garden ornamentals such as petunias (Petunia). Alkaloids are present in many species in this family and some species are deadly poisonous or contain known carcinogens. Genus info: The genus Nicotiana contains approximately 60 species, mostly in the Americas, of annual or perennial herbs or shrubs to small trees with alternate, mostly simple leaves. The flowers have funnel-shaped to salverform corollas with 5 stamens and produce dehiscent (splitting) capsules that contain many small, angled seeds. Most species have ill-smelling herbage and indigenous peoples reportedly smoked some species. The entire genus is poisonous to some degree and contains economically important species such as the tobaccos of commerce (N. tabacum and N. rusticum) and various garden ornamentals. Six species of Nicotiana are known to occur in San Diego County. The genus name is from J. Nicot, who supposedly introduced tobacco to Europe. Species info: Tree Tobacco is an introduced weed from northwestern Argentina and southern Bolivia that has naturalized in many habitats throughout our region and in other warm regions of the world. It is a glabrous, erect, sparsely branched shrub or small tree to 5 m tall with 516 cm long ovate, bluish-green, glaucous leaves. The tubular, cylindric, yellow to yellow-green flowers are 34 cm long and bloom throughout the year. The fruit is an ovoid capsule, that dehisces with 4 valves releasing many reddish-brown seeds. It is sometimes seen planted around houses, furnishing meager shade but requiring little care or water. Tree Tobacco attracts hummingbirds but repels livestock and is deadly to insects. This species has been used to treat rheumatism. The entire plant, especially the leaves, contains anabasine, a close relative of nicotine, and has caused poisonings and even deaths to humans. The specific epithet glauca is from Greek and means "bluish-gray," and refers to the thin waxy layer or whitish powder (bloom) that is found on some plant parts, especially the leaves. This species is native to South America, but has naturalized extensively in the southwestern and southeastern USA, Mexico, Africa, and the Mediterranean region.

Here are some pics taken by SDNHM Curator of Botany, J. Rebman, in January 2021 in a couple of our local urban canyons in San Diego. There is a lot of native botanical diversity in these canyons between neighborhoods and also many non-native plants that have naturalized there.

Crystalline Iceplant (Mesembryanthemum crystallinum) Fig-Marigold Family (Aizoaceae) Family info: Aizoaceae: The well-known leaf-succulent family Aizoaceae is represented in our region primarily by exotics known as iceplants (Mesembryanthemum and Carpobrotus spp.). However, a few native species, such as in the genera Sesuvium and Trianthema can be found in San Diego County. The large and diverse Fig-Marigold family contains 130 genera and approximately 2500 species worldwide,... but in our County only 17 species have been documented and most of these have escaped from cultivation and are native to southern Africa. The dry, dehiscent fruits of many species in this family respond to moisture and are closed when dry, but during wet conditions they open to release the seeds. The showy, linear, petal-like structures found in the flower of many members of this family are actually staminodes (modified and sterile stamens of the flower). Genus info: According to Michael Charters website (http://www.calflora.net/botanicalnames/pageMA-ME.html) on plant names for California the genus name is either derived from (1) two words: mesos, "middle," and embryon, "fruit," indicating a flower with its fruit in the middle, and/or (2) afternoon-blooming. The original name was Mesembrianthemum, from mesembria or "mid-day" alluding to the belief that the species only bloomed in the sunlight. After night-blooming species were discovered, the spelling of the name was changed to its current form. Some of these naturalized exotics are very aggressive weeds, such as the widespread, annual species of Mesembryanthemum, which can take over large tracts of disturbed habitat and accumulate and release salts into the soil, thus eliminating other plants from growing in the area. Species info: Crystalline Iceplant is a nonnative, low-growing annual or biennial with succulent, ovate to spatulate leaves to 20 cm long that are covered with large bladdery cells. These inflated cells give the plant a glistening appearance, like ice covering its surface, hence the common name iceplant. When stressed or with age, the whole plant commonly turns reddish in coloration; this can be seen easily in some coastal flats or beaches in our County where this species has invaded en masse. Crystalline Iceplant occurs mostly on the immediate coast in our region, but occasionally it occurs further inland in disturbed, saline habitats.

Here are some plant photos taken by J. Rebman in December 2020 at Horsethief Canyon in San Diego County. This area was burned in the Valley Fire in September 2020 and many of the plants are starting to regenerate after this wildfire.

Observation of the Month: Alligatorweed (Alternanthera philoxeroides) Amaranthaceae https://www.inaturalist.org/observations/58476888 by chrysaetos It’s on the official list of California noxious weeds, so the discovery of Alligatorweed (Alternanthera philoxeroides) in San Diego County was not welcome news. The observation posted by Jorge Ayon (@chrysaetos) a few months ago brought the plant to the attention of Jon Rebman and with Jorge’s assistance, he obtained a voucher spe...cimen to confirm the identification and document the plant’s presence in our county. Early detection of invasive species such as Alligatorweed is important to allow land managers to gain control of the population before it grows to the point where it cannot be eradicated locally and before it spreads to other locations. Alligatorweed can form dense floating mats when it invades lakes, ponds, streams, and irrigation ditches. It is native to South America. According to Cal-IPC, it was introduced in California when it was previously used in the aquarium trade. Efforts are underway to eradicate it in the San Joaquin Valley and Sacramento Delta areas. The leaves of Alligatorweed are elliptic, less than an inch wide and 5 inches long, and are opposite with entire margins. The inflorescence is spherical about inch in diameter with papery white flowers. Outside its native range, Alligatorweed is not known to produce seeds, but it still reproduces and spreads very easily by vegetative fragments.

Join Dr. Jon Rebman, SDNHM Curator of Botany, tomorrow evening for a virtual presentation entitled "Plant Rediscoveries in Baja California and Discoveries in San Diego" hosted by the San Diego Chapter of the California Native Plant Society (CNPS). Here is the link and info on how to listen in: https://www.facebook.com/events/391201835475760?active_tab=about

Here are a few plant pics taken in December 2020 by J. Rebman, SDNHM Curator of Botany, in San Diego County.

Puncture Vine (Tribulus terrestris) Caltrop Family (Zygophyllaceae) Species info: This uncommon non-native prefers disturbed habitats like vacant lots, along roads, sidewalks, etc. and is especially common in urban habitats. The species is native to the Mediterranean region, but has been introduced and has naturalized in much of the USA, Canada, Mexico, and Central & South Americas. It has many various common names such as Puncture Vine, Caltrop, and Goathead, all referring t...o the very spiny fruits that break apart into individual nutlets that easily puncture a bike tire or painfully penetrate a bare foot or hand. The specific epithet terrestris means on land and it is one of those weedy species you should be wary of when crossing any land. Genus info: According to M. Charters (http://www.calflora.net/botanicalnames/pageSI-SY.html), the genus name Tribulus is derived from the Greek tribeles or tribolos and Latin tribulus because of the three-spiked shape of the fruit which is similar to a caltrop, an ancient military weapon composed of an iron ball with projecting spikes that could be put on the battlefield to slow cavalry or soldiers. Family info: Zygophyllaceae: The Caltrop family includes 22 genera and 285 species in tropical semiarid and desert regions of the Old and New Worlds. Most members are herbs or shrubs, rarely trees, with branches jointed at the nodes and opposite or alternate leaves with well-developed stipules and often compound leaves with paired or even-pinnately arranged leaflets. In ours, the flowers are usually solitary in leaf axils and have 5 sepals, 5 petals, and a nectary disk. The fruits are variable in this family, but most of our species usually have a dehiscent (splitting) capsule or a schizocarp that splits into separate nutlets. In San Diego County, the family Zygophyllaceae is represented by 4 genera and 6 species. Probably the best known member of this family in our region is Creosote Bush (Larrea tridentata), which is a dominant shrub in desert areas such as the Anza-Borrego Desert State Park.

Common Catchfly (Silene gallica) Pink Family (Caryophyllaceae) Species info: The specific epithet gallica means of or from or referring to France. This species is native to Europe, but has naturalized in the western and southeastern USA and in northwestern Baja California, Mexico. It is most commonly found in our region in disturbed substrates along roads, trails, ditches, or in vacant lots. This non-native species is an annual, has opposite leaves, and white to pink flowers.... Genus info: The genus Silene is the most diverse genus in the Caryophyllaceae in San Diego County and is represented with eight species including the very attractive and rather common Southern Pink (Silene laciniata ssp. laciniata), which has bright red flowers. Many of the members in this genus have sticky, glandular hairs on their upper stems and sepals or glandular patches on the stem internodes, and because small insects frequently get stuck in these glandular areas they are sometimes called catchflies. According to M. Charters (http://www.calflora.net/botanicalnames/pageSI-SY.html), the genus name is derived from the Greek sialon, meaning "saliva" and refers to the sticky material on the stems, but it might be also named for Silenus, who was the drunken father of the god of wine and he was covered with foam, which resembles the glandular exudate found in many species of this genus. Family info: Caryophyllaceae: The Pink family has a worldwide distribution and includes 87 genera and 2300 species. In San Diego County, this family is represented with 19 genera and 42 species, but 22 of these species are non-native to our region. Members of this family are mostly annuals and herbaceous perennials with simple, opposite leaves, often swollen nodes, and flowers with 5 petals (sometimes deeply lobed or fringed) and a superior ovary that develops into a dehiscent (splitting) capsule. Ornamental pinks and carnations (of the genus Dianthus) are in this plant family; hence the common name for the entire family. See more

Castor Bean (Ricinus communis) Spurge Family (Euphorbiaceae) Species info: Castor Bean is a non-native shrub or small tree that has large, peltate leaves that can be colorful and attractive, and can cause contact dermatitis on some people. The name Castor Bean refers to the seed, (not a true bean as in the Fabaceae) and is the source of castor oil, which has a wide variety of uses. The seeds contain between 40% and 60% oil that is rich in triglycerides, mainly ricinolein. How...ever, the seed also contains ricin, a water soluble toxin that is present in lower concentrations throughout the plant, and should be avoided at all times because this poison is one of the most toxic compounds known. The specific epithet communis is Latin and refers to "common or general" and also means growing in communities. Native to northeastern Africa, introduced and widespread in the southern USA and Mexico; a pan-tropical weed. This weedy species has naturalized in our region and occurs sporadically in disturbed or wetland areas such as ditches, roadsides, vacant lots, and many riparian areas of our county. Genus info: The genus name Ricinus is Latin and comes from the fact that the seed of this plant closely resembles that of a Mediterranean sheep tick of the same name. Ricinus a monotypic genus meaning there is only one species in the genus. The species is monoecious with separate male (staminate) and female (pistillate) flowers occurring on the same individual, usually with the male flowers arranged below the female flowers. The fruit is spiny and produces rather large, smooth, shiny seeds that are mottled and resemble an engorged tick. Family info: Euphorbiaceae: The Spurge family is quite diversified with over 200 genera and 5700 species distributed almost worldwide. Some of the species, especially in Africa, look very similar to the Cactaceae of the New World and are good examples of convergent evolution (similar in look and form, but unrelated as plant groups). Some species are economically important and include the Rubber Tree (Hevea brasiliensis), Castor Bean (Ricinus communis), and Cassava (Manihot esculenta). Many members of the family have toxic, milky white sap that can cause strong reactions, i.e., dermatitis, in people with latex sensitivities. See more

Species info: Creeping Spurge (Euphorbia serpens) is in the Spurge Family (Euphorbiaceae). This species is native to South America, but has naturalized as a weed in disturbed habitats like gardens, roadsides, and sidewalks throughout much of the world. Genus info: The genus name Euphorbia honors Euphorbus who was a Greek physician to Juba II, King of Mauretania. However, his name is derived from eu meaning "good" and phorbe for "pasture" and literally means "well fed." Thus, ...it is a very appropriate name for a genus that has a lot of succulent members with fattened stems. Euphorbia species have a specialized, flower-like inflorescence called a cyathium (pl. cyathia) that consists of a single pistillate (female) flower surrounded by several reduced staminate (male) flowers that are all in a cup-like involucre that may have glands and petal-like appendages. Family info: Euphorbiaceae: The Spurge family is quite diversified with over 200 genera and 5700 species distributed almost worldwide. Some of the species, especially in Africa, look very similar to the Cactaceae of the New World and are good examples of convergent evolution (similar in look and form, but unrelated as plant groups). Some species are economically important and include the Rubber Tree (Hevea brasiliensis), Castor Bean (Ricinus communis), and Cassava (Manihot esculenta). Many members of the family have toxic, milky white sap that can cause strong reactions, i.e., dermatitis, in people with latex sensitivities. See more

Today, we are starting a new plant series on our website called "Urban Plants of San Diego" that will focus on plants that are commonly found in the urban areas of San Diego County. Of course, many of these species can be found in other urban and disturbed areas worldwide. This series will address both native and non-native species commonly called "weeds" that surround us where we live, but often go unnoticed. We will be using various photos of each plant's parts, map distributions in the County, and also general text on the plant family, genus, and species in which they are recognized. We hope that you enjoy this new series.

In honor of Mexico's National Cactus Day which was last Saturday, 10 October, here are a bunch of cactus photos from the Baja California region. Enjoy!

If you are a member of the San Diego Natural History Museum and want to join in for an informal coffee and convo discussion with our Botany Curator, Dr. Jon Rebman, it is tomorrow (Friday) morning. It is only for members (of course you can easily join the Museum) and it is a free event, but you need to register to get the Zoom link. Hope to see (virtually) you there!

Member Meetup: Dr. Jon Rebman, Botany Boss Friday, October 9, 2020 9:00 AM Want to be buddies with a botanist? Now’s your chance to meet the man, the myth, the legend, and the guy who often discovers lost plants: Curator of Botany Jon Rebman. ... This casual, 30-minute Q&A will take place live on Zoom, and is exclusively for members. This event requires advance registration and you can RSVP at https://www.sdnhm.org/join-and-gi/membership/member-events/ For questions, please email [email protected]. Not a member? Join or renew today by visiting us at www.sdnhm.org/membership.

Observations of the Month: Matilija Poppies (Romneya) Papaveraceae Hairy Matilija Poppy (Romneya trichocalyx) https://www.inaturalist.org/observations/6573028 by johnmartin...Continue reading

Observation of the Month: Southern Mule’s Ears (Agnorhiza ovata) Asteraceae https://www.inaturalist.org/observations/48989713 by lagoondon They all may have fuzzy leaves resembling the ears of America’s favorite pack animal, but the group of plants commonly known as mule’s ears belong to at least 3 different genera, with multiple species, only one of which is native to San Diego County. Southern Mule’s Ears (Agnorhiza ovata) is found in our upper foothills and mountains. Th...ey are conspicuous, but not common. The herbarium at the San Diego Natural History Museum holds only 53 voucher specimens of this species collected from our county. Observations from San Diego County of this species on iNaturalist which have been verified by Jon Rebman total only 46. All too often observations of Southern Mule’s Ears are incorrectly identified as Woolly Mule’s Ears (Wyethia mollis) on iNaturalist. Unfortunately, when photos of Southern Mule’s Ears are uploaded to iNat, Wyethia mollis usually appears as the top suggestion given by iNat’s computer vision model. (Agnorhiza ovata did not appear in the list of suggested species at all when I tested the system with multiple photos of Southern Mule’s Ears probably because of the small number of observations of the plant.) Young leaves of both plants are typically fuzzy or woolly making it easy to be led astray by the Woolly Mule’s Ears common name of the top computer vision suggestion. The issue is compounded by the fact that Agnorhiza ovata is still listed under its synonym, Wyethia ovata, by several sources, including Jepson eFlora and Checklist of Vascular Plants of San Diego County, so that Wyethia mollis may sound right even though it is not. Wyethia mollis is found in the central Sierra Nevada Mountains and farther north, not in Southern California. In addition to distributional range, the plants have other differences. The flower heads of A. ovata are smaller with fewer ray flowers compared to W. mollis. In general, the leaves of A. ovata are ovate and have a distinct petiole; W. mollis’s leaves are lanceolate and may not have a distinct petiole. Agnorhiza ovata lacks basal leaves, while W. mollis has more basal leaves than cauline (distributed along the stem) leaves. The outer phyllaries of A. ovata are leaf-like but those of W. mollis are narrow and barely, if at all, leaf-like. Our local species of mule’s ears is assigned to a genus that was apparently given its name from the Greek agnostos (unknown) and rhiza (root), due to initial uncertainty about the plants’ roots. Despite its name, don’t be agnostic when you identify mule’s ears! Be confident that mule’s ears observed in San Diego County are Agnorhiza ovata.

Some local botanists just brought us in a specimen of this new plant record to San Diego County. Unfortunately, it is a non-native annual composite species named Pulicaria arabica ssp. arabica that we do not want to spread throughout our County or California. This species was found in vernal pool habitats in the Miramar/Kearney Mesa area. It is just now coming into flower and has not yet set fruits this year. If you see this plant in the field anywhere in our region, please let us know! You can post it on iNaturalist and tag jrebman or send an email to [email protected]. Thanks and please be on the look out for it!

Here are some plant pics taken by J. Rebman, SDNHM Curator of Botany, in western San Diego County within the last week. Enjoy!

Here are some plant pics taken by J. Rebman, SDNHM Curator of Botany, during the holiday weekend in the vicinity of Chihuahua Valley to the north of Warner Springs in northern San Diego County.

Another week and another plant photo album! Here are some plant pics taken by J. Rebman, SDNHM Curator of Botany, during botanical fieldwork this last week.

Here are some plant pics taken by J. Rebman, SDNHM Curator of Botany, during botanical fieldwork this last week.