This document discusses native plants from the Sonoran Desert that can be used in gardens in Western Los Angeles County. It provides background on the different deserts in California, focusing on the Sonoran Desert and its Colorado Desert subdivision. The Colorado Desert has a diversity of plant life due to variable precipitation patterns, though it is hotter and drier than other parts of the Sonoran Desert. One highlighted plant is Indian Mallow, which thrives in local gardens because it is tolerant of some summer watering, unlike plants strictly adapted to desert conditions. By understanding the environmental needs of native plants, gardeners can select species suitable for the region's Mediterranean climate.

1. © Project SOUND
Out of the Wilds and Into Your Garden
Gardening with California Native Plants in Western L.A. County
Project SOUND – 2018 (our 14th year)

2. © Project SOUND
Plants of the Sonoran
Desert: their use in local
gardens
C.M. Vadheim, K. Dawdy (and T. Drake)
CSUDH (emeritus), CSUDH & City of Torrance
Madrona Marsh Preserve
February 3 & 6, 2018

3. 2018 Season – Gardens that sooth
© Project SOUND
Gardens that heal

4. So why are we talking about the Sonoran Desert?
© Project SOUND

5. Like it or not, our climate’s changing…
© Project SOUND
… and we need to learn how to cope without over-stressing

6. The Sonoran Desert is one of three
California deserts
© Project SOUND
 Great Basin Desert – ‘cold desert’
‘shrub steppe’ [Owens Valley]
 Mojave Desert – ‘high desert’
[Joshua Tree; I15 to Las Vegas]
 Sonoran (Colorado) Desert – ‘low
desert’ [Anza-Borrego]
http://www.mbgnet.net/sets/desert/ofworld.htm

7. The three deserts share some characteristics
– because they are hot, dry deserts
© Project SOUND
Hot summers
Dry
Sparse vegetation
https://en.wikipedia.org/wiki/Mojave_Desert

8. What are deserts? It’s all about water.
 Many types of definitions.
 Precipitation: ‘Receive less than 10
inches (250 mm) of average annual
precipitation’ (semi-deserts receive 10-
20 in. year).
 Aridity - high rates of water loss from
the ground (evaporation) and through
plants (transpiration); may actually
exceed precipitation
 "A biological community in which most
of the indigenous plants and animals are
adapted to chronic aridity and periodic,
extreme droughts, and in which these
conditions are necessary to maintain
the community's structure.’
© Project SOUND
https://www.pinterest.com/pin/476044623083723828/?lp=tr
ue

9. What are deserts? Aridity produces many
other climatic features of deserts.
 Uneven and unpredictable nature of the
little precipitation that occurs
 Wide temperature range (both high and
low) due low humidity
 Windy – due temperature extremes
 Intense sunlight due low humidity
© Project SOUND
https://www.pinterest.com/pin/476044623083723828/?lp=tr
ue

10. How many types of deserts are there?
 There are almost as many
definitions of deserts and
classification systems as there
are deserts in the world.
 Deserts are often classified by:
 Temperature: hot vs. cold
 Amount of precipitation: dry vs.
semi-arid
 Etiology (cause):
 Coastal deserts
 Mid-latitude deserts
 Rain-shadow deserts
© Project SOUND
Hot deserts
https://en.wikipedia.org/wiki/Desert_climate
It turns out our California deserts can be explained by several etiologies

11. Precipitation and the atmosphere are closely
linked: on both macro & micro- levels
 Atmospheric thermodynamics is extremely
complicated, but the basic rules are simple.
 First, hot air rises and cool air sinks.
 Second, rising air expands and cools, while
sinking air compresses and becomes warmer.
 Third, warmer air can hold more water
vapor than cooler air.
© Project SOUND
http://dougrobbins.blogspot.com/2014/05/hadley-cells-global-distribution-of.html
 These three natural phenomena, plus the sun's heat,
determine where rain falls on the planet.

12. Why most warm dry lands are at mid-latitudes
 The tropical atmospheric convection cell is
known as the Hadley cell (Hadley circulation).
 Warm air rises near the equator, spreads
laterally, becomes cool and falls at around 30
degrees latitude, north and south.
 As the warm air rises at the equator, it
cools, dropping its moisture as rain. Tropical
rainforests are the result, circling the
globe near the equator.
 The air moves north and south to about 30
degrees of latitude and falls. As the high-
altitude cool air becomes warmer in the
lower atmosphere, its relative humidity falls.
The descending air-mass is dry, and deserts
circle the globe between 25 degrees and
30 degrees of latitude.
© Project SOUND
http://dougrobbins.blogspot.com/2014/05/hadley-cells-
global-distribution-of.html

13. Why do deserts occur? Location, location,
location
 Mid-latitude deserts: are
also far enough from the
coast that even less
moisture remains
[example: Sonoran Desert;
Great Basin Desert]
 Rain-shadow deserts:
blocked from coast by
mountain range; moisture
dropped on the ocean side
of the mountains [Mojave
Desert]
© Project SOUND
http://chanelo.co/sonoran-desert-on-us-map/sonoran-desert-wryheat

14. California’s deserts are due to a unique
combination of factors
 Latitude (in the ‘dry’ part of the
Hadley Cell)
 Location on West Coast is
influenced by ocean temperature
patterns California Current
 Distance from the wetter coast
 Mountain ranges (Sierra Nevada,
Transverse and Coastal Ranges)
create a rain shadow to their east
© Project SOUND
https://en.wikipedia.org/wiki/Geography_of_California

15. Not surprising that our three deserts are
also different in significant ways
© Project SOUND
Sonoran Desert
http://geography5ecosystem.blogspot.com/
Great Basin Desert
http://archive.bio.ed.ac.uk/jdeacon/desbiome/basin.htm
Mojave Desert
https://www.beautifulworld.com/north-america/united-
states/mojave-desert/

16. Comparing our three CA deserts
Temperature Ave. Rainfall Elevation Vegetation
Great
Basin
[north]
Cold winter/
warm summer
Varies with
elevation;
some 10-20
inches
Highest: to
11,000 feet
Cold-temperature
limited; Sagebrush
Mojave
[central]
Cool winter/
hot summer
3 to 10 inches
Mostly winter
Mid-range;
includes dry
mountains >
7000 ft.
Cold/hot temperature
and winter
precipitation limited;
Joshua trees and
scrublands
California
Sonoran
(Colorado)
[south]
Mild winter/
hottest
summer
2 to 6 inches
Winter &
Summer
Lowest: < 1000
ft.; peaks <
3000 ft
Precipitation limited;
legume trees, more
varied plant
communties
© Project SOUND

17. The Sonoran Desert (as a whole)
© Project SOUND
 Approximately 100,000 square miles –
mostly in AZ, Baja, Sonora Mexico
 One of the wettest of the world’s
deserts: annual precipitation averages
from 76 to 500 mm (3–20 in)
 Substantial inter- and intra-annual
variability in timing and quantity of
precipitation.
 Precipitation is typically much higher with
elevation, (the sky islands), with a sizable
proportion occurring as snowfall.
 Most areas experience both gentle winter
& more dramatic summer precipitation
https://www.desertmuseum.org/desert/sonora.php

18. Why summer monsoons: Sonoran Desert?
 The Sonoran is hot: summer air
temperatures routinely exceed 40°C
(104°F), often reach 48°C (118°F).
 High near-surface temperatures
cause an area of surface low
pressure. This sucks in moisture-
laden air from the Gulf of Mexico
 The hot air interacts with cool,
moist air in the atmosphere to
produce the violent thunderstorms
of the summer monsoons.
 As moisture on the soil surface and
near-surface air evaporate following
a storm, temperatures may drop
10°C (50°F) or more, often within a
matter of minutes.
© Project SOUND
https://tjsgardendotcom1.wordpress.com/tag/weather-in-the-sonoran-desert/

19. Summer moisture defines the Sonoran Desert
 Makes it more tropical (at
least further South)
 Makes the flora more
complex; trees to annuals,
many unique endemics
 Increases plant
biodiversity: > 2000 plant
species (high for a
desert). Most biodiverse
N. American desert
© Project SOUND
 Many of the perennial plants and animals are derived from
ancestors in the tropical thornscrub to the south, their life
cycles attuned to the brief summer rainy season.
http://geography5ecosystem.blogspot.com/2012/11/historical-state-of-sonoran-desert.html
Legume trees Columnar cacti

20. Many other species depend on the winter rains
© Project SOUND
https://coastsideslacking.com/2017/03/30/super-bloom-part-1-anza-borrego-wildflowers-defy-expectations-but-we-are-
impressed-anyway/

21. Annuals make up half the Sonoran Desert plant
species: most are winter rain-dependent
© Project SOUND
http://blog.sandiego.org/2013/03/wildflowers-east-county/

22. California’s part of the Sonoran Desert is small…
© Project SOUND
…and, as it turn out, not that typical

23. California’s part of the Sonoran Desert is
called the ‘Colorado Desert’
 ~ 7 million acres (2,800,000 ha).
 Imperial County, parts of San Diego County,
Riverside County, and a small part of San
Bernardino County.
 Coachella Valley area:
Palm Springs
Palm Desert
Indio
Indian Wells
Rancho Mirage
Cathedral City
Borrego Springs
 Imperial Valley area
El Centro
Calexico
Brawley
© Project SOUND
http://mojavedesert.net/plants/vegetation/01.html
Lower Colorado River Valley
area
Blythe
Palo Verde
Winterhaven

24. The Lower Colorado River Valley sub-
division of the Sonoran Desert: hot & dry
 Largest, hottest, and driest subdivision of
the Sonoran Desert (challenges the
Mohave Desert's Death Valley as the
hottest and driest place in North America).
 Summer highs may exceed 120°F (49°C),
with surface temperatures approaching
180°F (82°C).
 Annual rainfall in the driest sites averages
less than three inches (76 mm), and some
localities have gone thirty-six months with
no rain. Even so, life exists here,
abundantly in the rare wet years.
© Project SOUND
https://www.desertmuseum.org/books/nhsd_biomes_.php

25. The Colorado Desert has interesting
topography & geology
 Most lies at a relatively low elevation,
below 1,000 feet (300 m) (lowest
point at the Salton Sea).
 Although the highest peaks of the
Peninsular Ranges reach elevations of
nearly 10,000 feet (3,000 m), most of
the region's mountains do not exceed
3,000 feet (910 m).
 Geology is dominated by the transition
of the tectonic plate boundary from
rift to fault. The southernmost
strands of the San Andreas Fault
connect to the northernmost
extensions of the East Pacific Rise.
© Project SOUND
 The region is subject to
earthquakes, and the crust
is being stretched, which
will result in a sinking of
the terrain over time.

26. Landforms of the Colorado Desert
 Reflect ancient history of
volcanos and ancient seas
 Volcanic rocks exposed in some
places (mountain ranges)
 Sedimentary rocks from
ancient shallow sea beds
 Soils and landforms shaped by:
 Water erosion
 Wind erosion
 Temperature extremes
© Project SOUND
https://www.desertmuseum.org/books/nhsd_geologic_origin.php

27. Mountains ring the central lowlands
 The terrain consists mostly of
broad, flat valleys with widely-
scattered, small mountain ranges of
almost barren rock.
 Mountain ranges:
 Around the east side of Joshua Tree
NP in the north (the Orocopia
Mountains, the Chuckwalla Mountains,
the Coxcomb Mountains)
 In Anza-Borrego Desert State Park
 The Colorado River ranges
(Chemehuevis, Whipples, Big Marias).
© Project SOUND
https://commons.wikimedia.org/wiki/File:Wpdms_shdrlfi020l
_little_san_bernardino_mountains.jpg

28. The Colorado Desert flora is determined
by its dry conditions
 Home to many unique flora and fauna. But
overall plant biodiversity lower than in other
parts of the Sonoran Desert
 Valleys are dominated by low shrubs.
 Trees grow only along the larger washes and
at higher elevations.
 Mountains support a wider variety of shrubs
and cacti, but density is still very sparse.
 Columnar cacti, one of the indicators of the
Sonoran Desert, are virtually absent in
California
 Annual species comprise over half the flora,
and up to 90% at the driest sites
© Project SOUND
http://www.americansouthwest.net/california/anza_borreg
o_desert/yellow-agave_l.html

29. Might not seem to be a good place to look for
candidates for Western L.A. County Gardens
© Project SOUND

30. In fact, the Colorado Desert’s diversity means that
some plants are good candidates
© Project SOUND

31. But we need to understand their needs
and then choose wisely
© Project SOUND

32. Plant communities important for Los
Angeles Co. gardens
 Which desert plants are
appropriate?
 What will the future hold?
© Project SOUND
http://www.ethnoherbalist.com/southern-california-native-plants-medicinal/

33. © Project SOUND
* Indian Mallow – Abutilon palmeri

34. © Project SOUND
* Indian Mallow – Abutilon palmeri
 Low desert of S. California (Colorado
Desert) and on the eastern slopes of the
peninsular range & San Jacinto Mtns
 Dry east-facing mountain slopes, washes,
creosote bush scrub, elevation: 1800-2400'
http://cabezaprieta.org/plant_page.php?id=1054
http://www.slingshotforums.com/threads/saturday-june-4th-san-diego-laguna-
mountain-classic.12849/

35. © Project SOUND
Indian Mallow adds interest
to many gardens
 As a specimen shrub – color, texture
 In a habitat garden
 Along a hot wall; with other water-
wise native like Salvias, Penstemons,
Eriorgonums, Ceanothus
 Anywhere you need a nice shrub –
very shapeable
https://queenofthedirt.blog/2017/04/04/tpfnpgt-saturday-part-deux/
http://www.plantmaster.com/gardens/eplant.php?plantnum=24577

36. Why does Abutilon palmeri do so well in
local gardens? Why a good fit?
© Project SOUND

37. Desert vs Mediterranean Climate
Desert - Extremes
 Precipitation: < 10 inches
 Aridity: high almost all year
 Precipitation pattern:
 Highly unpredictable year-to-
year;
 May fall in either winter or
summer
 Temperatures: extreme highs
and lows
 Windy most of year
 Intense sunlight
Mediterranean Climate -
moderation
 Precipitation: > 10 inches
 Aridity: high only in late
summer/fall
 Precipitation pattern:
 Somewhat unpredictable
 Falls as rain in winter
 Temperatures: moderated by
proximity to ocean
 Seasonal winds
 Less intense sunlight; clouds and
humidity moderate
© Project SOUND

38. Desert plants that might succeed
 Better if had some tolerance
of yearly precipitation
extremes – particularly on the
‘wet’ side
 Better choices might be able
to take some summer water
(because they might look
better than those that can’t)
© Project SOUND
https://www.houzz.com/photo/53631956-abutilon-palmeri-palmers-indian-mallow-
landscape-los-angeles
Sonoran Desert plants meet at least one of these criteria

39. The Sonoran Desert looks more complex
than the Mojave Desert
© Project SOUNDhttps://cactiguide.com/article/?article=article5.php
http://granite.ucnrs.net/?page_id=869

40. © Project SOUND

41. The Colorado Desert has a range of biozones,
most strongly defined by elevation and drainage
© Project SOUND
https://www.nps.gov/im/sodn/ecosystems.htm
https://en.wikipedia.org/wiki/Lower_Colorado_River_Valley
Plants from some Colorado Desert communities are
better suited than those from others

42. Plant Communities: Colorado Desert
 Pinyon-Juniper Woodland
 Mixed Scrub
 Creosote Bush Scrub
 Saltbush Scrub
 Alkali Sink
 Psamnophytic Scrub
 Microphyll Woodland
 Palm (Desert Woodland) Oasis
© Project SOUND
https://www.nps.gov/im/sodn/ecosystems.htm
https://en.wikipedia.org/wiki/Lower
_Colorado_River_Valley

43. Let’s take a road trip to explore the most
important communities
© Project SOUNDhttp://gotbooks.miracosta.edu/geology/regions/colorado_desert.html

44. A good start is
© Project SOUND
classic Mojave Desert
http://www.hiking-in-ps.com/joshua-tree-national-park/
http://www-
personal.umich.edu/~alanford/nancyford/photoalbums/califor
niamarch2002/page4.htm
Colorado Desert

45. Joshua Tree National Park is a good
place to compare/contrast deserts
© Project SOUND
http://mojavedesert.net/plants/vegetation/01.html

46. Pinyon-Juniper
woodland
 Desert side of the mountains,
generally the eastern slopes of
north-south trending ranges and the
northern slopes of east-west
trending ranges
 Elevations from about 5000' to
8000'-9000', extending from the
Tehachapi Mountains southward and
including the higher mountains of
the Colorado Desert.
 1070 to 1680 m (3500 to 5500 ft)
in the San Jacinto and Santa Rosa
Mountains
© Project SOUND
http://mojavedesert.net/habitat/pjn.html
http://www.highonadventure.com/hoa17nov/lee/joshua-tree.htm

47. Pinyon-Juniper
Woodland is a
pleasant surprise
 Found in ‘Sky Islands’ throughout
the Southwest
 Remnants of woodlands that were
far more extensive in wetter past
 We’ll come back to the Pinyon-
Juniper Woodland next month
© Project SOUND
https://www.cheersnature.com/exploring-santa-rosa-and-san-jacinto-mountains-
national-monument-southern-ca/
Joshua Tree National Monument
• Hidden Valley Nature Walk
Santa Rosa & San Jacinto Mountains
National Monument

48. Santa Rosa & San Jacinto Mountains
National Monument
© Project SOUNDhttps://commons.wikimedia.org/wiki/File:Santa_Rosa_and_San_Jacinto_Mountains_283.jpg

49. Santa Rosa & San Jacinto
Mountains National
Monument
© Project SOUND
https://media-cdn.tripadvisor.com/media/photo-s/09/47/16/e0/san-jacinto-national.jpg
https://it.pinterest.com/pin/57420963980602482/
• Jointly managed by the BLM and the U.S.
Forest Service
• The Monument includes two Federal
wilderness areas -- the Santa Rosa and the
San Jacinto.

50. Santa Rosa & San Jacinto Mountains
National Monument
 Established by an Act of Congress on October 24, 2000, "in
order to preserve the nationally significant biological, cultural,
recreational, geological, educational, and scientific values found
in the Santa Rosa and San Jacinto Mountains"
© Project SOUND

51. The Santa Rosa & San Jacinto Mountains
National Monument is an ecological gem
 Large elevation range: sea level to nearly
11,000 feet (3,400 m).
 San Jacinto Peak is the highest point in
the Peninsular Range Province and has
one of the steepest fault-block
escarpments in North America
 The differences in elevation,
temperature, and moisture give rise to
diverse vegetation
 Pine Forest
 Woodlands
 Riparian
 Desert Oasis Woodland
 Chaparral
 Desert Scrub
© Project SOUND
https://www.blm.gov/programs/national-conservation-
lands/california/santa-rosa-and-san-jacinto-mountains-national-
monument

52. We’ll visit the Palm Oases next month:
they contain plants useful in gardens
© Project SOUND
https://en.wikipedia.org/wiki/Washingtonia_filifera

53. Mixed desert scrub plant community
 Plant community of rocky desert
slopes between 500-5000 ft
elevation.
 Both Mojave and Sonoran Deserts.
 Varies floristically with latitude,
rainfall, and substrata.
 Although it intergrades below with
creosote bush scrub, cactus scrub,
desert wash scrub, or microphyll
woodland and above with blackbush
scrub and pinyonjuniper woodland it is
distinct from these.
 There are no obvious dominants,
 Little studied – needs work.
© Project SOUND
https://califlorana.wordpress.com/2015/05/01/the-untapped-
potential-of-deserts-my-field-botany-trip-to-the-mojave-and-colorado-
deserts/
http://range.altervista.org/Shrublands/sonorandesert.html

54. Mixed desert scrub: complex mixture
 Impressive mixture of species
displaying most of the various
desert growth habits:
 Stem-succulent cacti
 Leaf semisucculents like Agave
and Yucca spp.
 Leaf-succulents of the genus
Dudleya, the ocotillo, Fouquieria
splendens
 Many shrubby desert species
 Perennial herbs
 Perennial grasses
 Ferns
 Many annuals, especially of the
genera Eriogonum, Gilia, and
Phacelia.
© Project SOUND
https://www.fs.fed.us/wildflowers/beauty/Sky_Islands/communities/desertscrub.shtml
 More developed in AZ, NM but also
found in Colorado Desert
 Examples: Santa Rosa & San
Jacinto Mountains National
Monument; Anza-Borrego

55. © Project SOUND
*Emory’s rock daisy – Perityle emoryi
©2013 Debra L. Cook

56. © Project SOUND
*Emory’s rock daisy – Perityle emoryi
http://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=4303
http://www.smmflowers.org/bloom/species/Perityle_emoryi.htm
http://www.birdandhike.com/Veg/Species/Forbs-A/Perity_emo/_Per_emo.htm
 Coastal bluffs, desert plains, slopes, washes; 10-
1500 m; Ariz., Calif., Nev., Utah; Mexico; South
America (Chile, Peru).
 Widespread polyploid of diverse habitats. The
range of appears to be gradually expanding.
 Collected by just about everyone: Leroy Abrams,
Brandegees, Parish

57. © Project SOUND
Cute little rock daisy : garden sized
 Size:
 1-2 ft tall
 1-2 ft wide
 Growth form:
 Annual or short-lived herbaceous
perennial
 Highly variable characteristics;
may be simple or many-branched
 May be hairy or not
 Foliage:
 Small round or triangular leaves;
toothed or lobed
 Color: medium green
Gerald and Buff Corsi © California Academy of Sciences.

58. © Project SOUND
Daisy-like flowers
 Blooms: mostly after
spring/summer rain but may be
almost all year
 Flowers:
 Petite daisy heads; ½ to 1
inch (at most)
 Small number of ray flowers
are pure white
 Disk flowers yellow
 Good pollinator flowers
 Seeds:
 Typical sunflower – easy to
start from seed
 Gather dry seed and save – or
let plants re-seed
©2012 Neal Kramer

59. © Project SOUND
Plant Requirements  Soils:
 Texture: well-drained sandy soil
best; likely accepts other
 pH: any local
 Light:
 Full sun to part-shade; OK with
dappled shade or afternoon
shade
 Water:
 Winter: need good winter water;
supplement if needed
 Summer: 1-2 times/mo. in
ground (more often in pots) –
Water Zone 1-2 to 2
 Fertilizer: none; likes poor soils
 Other: gravel or no mulch to insure
re-seeding
©2015 Wynn Anderson

60. © Project SOUND
Rock daisy in Garden
 Perfect plant for an accent
container – takes a little water
 Nice in rock garden, drystone
wall, desert garden – takes heat
 Dry edges of vegetable garden
 Under trees; as a filler (will
naturalize)
©2013 Robert Sikora
https://www.naturesfinestseed.com/desert-daisy
http://www.smmflowers.org/bloom/species/Perityle_emoryi.htm

61. Characteristics of CA Deserts important
for gardeners
 Yearly precipitation: generally low, but varies with elevation
 Precipitation distribution: winter, summer or both
 Temperature extremes
 Humidity
 Soil texture: generally sandy, rocky, well-drained
 Soil pH: generally neutral to alkali
 Soil fertility/organic content: generally low
 Water table/soil moisture: generally dry but depends on
drainage
 Organic mulch: generally none to very little
© Project SOUND

62. Getting around the difference in temperature
extremes between desert & coast
 Plants from intermediate
elevations don’t experience
as extreme highs
 Use plants that tolerate a
little shade – likely will
appreciate cooler
temperatures as well
 Climate change may be
making the coast more like
the inland anyway.
© Project SOUND©2015 Wynn Anderson

63. Why more diversity/large shrubs in mixed
scrubland community?
 More water overall (higher elevation or other)
 Concentrated in places that naturally conserve water:
 North-facing slopes
 Canyons
 Rocky places
 Bottoms of slopes
© Project SOUND
https://guideofus.com/california/joshua-tree-national-park

64. © Project SOUND
*Woolly bluestar – Amsonia tomentosa
©2004 Brent Miller

65. © Project SOUND
*Woolly bluestar – Amsonia tomentosa
©2000 Carol Bruce ©2000 Carol Bruce
 CA, s. NV, UT, AZ, NM, w. TX and northern
Mexico (Chihuahua); Mojave & Colorado
(Sonoran) Deserts
 Dry slopes, washes and flats, 2000'-5500',
often sandy or gravelly, in Creosote Bush Scrub,
Pinyon-Juniper Woodland & Joshua Tree
Woodland communities
 Collected by S. B. Parish
http://ucjeps.berkeley.edu/cgi-bin/get_cpn.pl?AMTO2

66. © Project SOUND
Wooly bluestar: herbaceous perennial
 Size:
 1-2 ft tall
 2-5 ft wide
 Growth form:
 Herbaceous or delicate sub-shrub
 Slender stems from woody stalk;
adds new stems each year
 Some plants are white-wooly
 Foliage:
 Green or more gray-green
 Leaves simple, lance-shaped with
pointed tip
 Looks very much like a garden
plant
©2004 Brent Miller

67. © Project SOUND
Flowers like small
Stephanotis
 Blooms: after winter-spring
rains – usually March-May
 Flowers:
 Clusters of flowers, mostly
at ends of stalks
 Flowers tubular with open
petals
 Flowers usually white with
yellow; may be pastel purple
or pink
 Very attractive; nice cut
flower
 Seeds: in a pod
©2006 Steve Matson
http://www.americansouthwest.net/plants/wildflowers/amsonia-tomentosa.html

68. What’s the deal with
pods & deserts?
 Benefits in dry climate:
 Allows seeds more time to
grow before drying out
 Larger seed has longer ‘shelf-
life’ – can wait until
conditions are right to
germinate
 Pod provides some protection
against predators
© Project SOUND
http://www.birdandhike.com/Veg/Species/Forbs-P/Amsoni_tom/_Ams_tom.htm
http://www.hazmac.biz/051212/051212AmsoniaTomentosa03.html

69. © Project SOUND
Plant Requirements
 Soils:
 Texture: sandy or rocky best;
well-drained
 pH: any local
 Light:
 Full sun to part-shade
 Water:
 Winter: needs good
winter/spring rains; supplement
if needed
 Summer: occasional water ok –
Water Zone 1-2 to 2
 Fertilizer: none; likes poor soils. In
containers, dose of ½ strength as
stems start to grow.
 Other: prune back old stems as
needed
©2004 Brent Miller

70. © Project SOUND
Adds interest to garden
 Well suited for a pot plant; even
on part-shady porch
 In desert themed garden or
mixed water-wise bed
 Contrast for evergreen shrubs
 Interesting in rock garden or
with bulbs, annuals
©2010 Neal Kramer
https://www.inaturalist.org/taxa/75427-Amsonia-tomentosa

71. Anza-Borrego Desert State Park
© Project SOUND
http://www.theabf.org/wildflowers

72. Anza-Borrego
Desert State Park
 The largest state park in California (>
600,000 acres).
 Eastern side of San Diego County, with
portions extending east into Imperial
County and north into Riverside County
© Project SOUND
http://www.travelcaffeine.com/anza-borrego-desert-state-park-
wildflower-super-bloom/

73. Be sure to visit the Desert Garden at the
Visitor Center
 Great example of
desert-type
garden
 May inspire you to
look ‘outside the
box’ in terms of
garden design
© Project SOUND
https://russbishop.photoshelter.com/image/I0000G2xxf8QCQcg

74. Complex topography/geology of Anza-
Borrego
 Framed by, and includes many
rugged mountain ranges:
 The Bucksnorts and the Santa
Rosas on the north, the
Jacumba Mountains on the south
and the Vallecito and Pinyon
Mountains on the west.
 To the east, the Borrego
Mountains taper into the Carrizo
Badlands before falling away
into the Salton Trough.
© Project SOUND
https://en.wikipedia.org/wiki/Anza-Borrego_Desert_State_Park
 The park contains bajadas and desert washes; rock formations
and colorful badlands, large arid landscapes, and mountains

75. Mixed Desert Scrub is common at Anza-
Borrego
© Project SOUND
https://www.fs.fed.us/wildflowers/beauty/Sky_Islands/commu
nities/desertscrub.shtml
https://www.travel-experience-live.com/anza-borrego-desert-wildflowers-superbloom-
photos/
Some of the plants are perfectly suited for home gardens

76. CA Encelia is pretty drought tolerant
© Project SOUND

77. © Project SOUND
*Acton brittlebush – Encelia actoni
Robb Hannawacker

78.  Native to CA, NV and Baja California
Locally N. slopes of San Gabriels
 Mountains of Mojave, Sonoran & Great
Basin Deserts; rocky slopes in desert,
chaparral, and grassland communities
from 2,500 to 6,000 feet elevation.
 Sometimes AKA Encelia actonii; collected
July 1, 1885 M.K. Curren [Brandegee]
© Project SOUND
*Acton brittlebush – Encelia actoni
©1999 Larry Blakely ©2007 Steve Matson
https://www.cpp.edu/~jcclark/encelia/act-m.html

79. © Project SOUND
Brittle Bush – Encelia farinosa
https://en.wikipedia.org/wiki/Encelia_farinosa

80. © Project SOUND
Brittle Bush – Encelia farinosa
 Interior valleys of S. CA, AZ and s. into
Mexico; Sonoran and Mojave deserts
 Dry, rocky slopes (bajadas); brushy areas;
flats and desert washes ; can dominate S-
facing Sonoran Desert slopes
 Many communities: open oak woodlands, semi-
desert and desert grasslands, desert scrub,
and coastal sage scrub
http://www.graniteseed.com/seeds/seed.php/Encelia_farinosa
http://www.laspilitas.com/nature-of-california/plants/261--encelia-farinosa
Anza-Borrego
http://www.natureathand.com/Main/Gallery/Encelia_farinosa_57712.htm

81. © Project SOUND
Brittle Bush: a mounded desert sub-shrub
 Size:
 3-5 ft tall
 3-5 ft wide
 Growth form:
 Mounded sub-shrub with woody,
succulent base
 Evergreen or drought-deciduous
 Fast growth; relatively short lived
(5-10 years)
 Foliage:
 Young spring leaves are greenish
 Summer set of leaves wooly & very
white –dramatic looking
 Allelopathy – prevents competition
 Roots: taproot with many shallow
laterals; resents being moved

82. © Project SOUND
Plant Requirements
 Soils:
 Texture: should be well-drained;
sandy/gravelly best
 pH: any local, including alkali (7.0-
9.00)
 Light: full sun, including reflected
heat.
 Water:
 Winter: may ‘drown’ in poorly
drained soils in wet years
 Summer: very drought tolerant
(Zone 1); perhaps best Zone 1-2
(very occasional water
 Too much water causes fast,
brittle growth
 Fertilizer: none; likes poor soil
 Cut back in fall/winter to promote
new growth

83. © Project SOUND
Sunflower heads above the foliage
 Blooms:
 Primarily in spring (Mar-May)
 May bloom sporadically at other
times in response to rain
 Flowers:
 Typical yellow & brown sunflower
heads
 Heads held on slender stalks above
the foliage – quite unique and
showy
 Sweet-scented
 Attracts insect pollinators
 Seeds:
 Typical for Sunflowers; birds love
them
 May be many seedlings in response
to heavy winter rains

84. © Project SOUND
Desert gardeners love
Brittle Bush
 Popular in desert landscaping
 Good choice for mixed dry
borders and rock gardens
 Does well on dry slopes
 Good choice for habitat gardens
 Good for ‘Evening Garden’
 Don’t plant: choose CA Encelia
instead
 Near coast
 Any area near natural populations
of CA Encelia
 Common name ‘Incienso’ refers to
scented stem resin which is dried
and used for incense.
http://www.plantmaster.com/gardens/eplant.php?plantnum=1391

85. Plant families common in the Sonoran
(Colorado) Desert
 Asteraceae – Sunflower family
 Cactaceae – Cactus family
 Fabaceae – Pea family
 Malvaceae – Mallow family
 Rosaceae – Rose family
© Project SOUND
https://www.yelp.com/biz/anza-borrego-desert-state-park-borrego-
springs-3

86. How do plants in the Sunflower family
survive in the Sonoran Desert?
 Grow in places with a little extra
water
 Along waterways/drainage
 Higher elevations
 Summer dormancy
 Drought-deciduous leaves – or two
set of leaves
© Project SOUND

87. © Project SOUND
Conserving water: 2
sets of leaves
 Plants react to seasonal increase
in water stress at the end of
the rainy season by replacing
the larger, less hairy leaves
produced earlier in the growing
season with hairy leaves that
are smaller and thicker.
 This reduces water loss and
regulates leaf temperature, but
it also decreases photosynthetic
capacity.
 Prolonged drought leads to
dormancy and leaf drop.

88. Plants of the bajadas & washes…
© Project SOUND
https://borregohiking.com/hiking/coyote_mountain_loop.html
… can be good candidates for the S. CA garden

89. Anza-Borrego Desert State Park is a good
place to observe bajada plants
 The bajadas are predominantly
creosote bush-bur sage with
creosote bush (Larrea
tridentata) and the palo verde-
cactus shrub ecosystems with
the palo verde tree
(Parkinsonia microphylla), cacti,
and ocotillo.
 They often also include other
shrubs and annual wildflowers
© Project SOUND
http://calebgolston.blogspot.com/2013/11/anza-borrego-desert-state-park.html

90. © Project SOUND
*Paper flower – Psilostrophe coorpei
©2016 Richard Spellenberg

91. © Project SOUND
*Paper flower – Psilostrophe cooperi
http://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=4503
©2010 Jean Pawek
©2010 Neal Kramer
 Southwest United States (California, Nevada,
Utah, Arizona, and New Mexico) and northern
Mexico. In CA: Mojave & Colorado (Sonoran)
Deserts
 In washes and gravely hillsides, at 2,000 to
5,000 feet in elevation
 Leroy Abrams, the Brandegees, S.B. Parish and
others all collected it

92. © Project SOUND
Paper flower: sunflower desert sub-shrub
 Size:
 1-2 ft tall
 1-2 ft wide
 Growth form:
 Mounded sub-shrub; nice natural
form & fast-growing
 Many slender branches
 Drought-deciduous or nearly
evergreen w/ water
 Foliage:
 Pale green, hairy foliage
 Thin almost linear grayish leaves
to 2 inches long
 Young plants somewhat toxic
to browsing livestock
©2012 Jean Pawek

93. © Project SOUND
Flowers keep on giving…
 Blooms: after rains – mainly spring
but also summer (Mar-Jul; Aug-Oct)
 Flowers:
 Pretty yellow sunflower heads;
like yellow Coreopsis
 Relatively few, broad ray
flowers with notched tips; dry
and become pale, but stay on
plant – ‘paper flowers’
 Yellow disk flowers
 Excellent habitat for pollinators
and birds
 Seeds: sunflower-type; easy to
grow from seed
©2010 Neal Kramer
©2008 Steve Matson

94. © Project SOUND
Easy plant for
our area
 Soils:
 Texture: most well-drained –
tolerant, but needs drainage
 pH: any local
 Light:
 Full sun to very light shade; this
is a sun-lover that can take heat
 Water:
 Winter: adequate (6-8 inches);
supplement as needed
 Summer: once or twice a month
from June-Aug (Water Zone 1-2
to 2 for best appearance
 Fertilizer: none; likes poor soils.
containers need ½ strength in late
winter
 Other: lightly head back in fall
©2010 Jean Pawek

95. © Project SOUND
Easy to love shrub
 Massed or as accent plant
 In habitat garden
 Fronts of beds; lining walkways
 As an attractive pot plant
 Even around the vegetable garden
©2011 Neal Kramer
©2003 Michael Charters
http://gardenoracle.com/images/psilostrophe-cooperi.html

96. How do plants in the Sunflower family
survive in the Sonoran Desert?
 Grow in places with a little extra
water
 Along waterways
 Higher elevations
 Summer dormancy
 Drought-deciduous leaves
 Annual life-style; get everything
over with before the summer
drought
 Produce lots of seed; take full
advantage of ‘good years’
© Project SOUND

97. What are those desert shrubs?
© Project SOUND
©2012 Jean Pawek

98. Throughout much if the Mojave and
Colorado Deserts, Creosote bush is king
© Project SOUND
http://map-state.bid/map-of-colorado-desert-in-california.html

99. Creosote bush scrub
 Common: ~ 70 of area of
Mojave/Colorado Deserts
 Lower slopes to about 3500‘
 Well-drained soils
 Very high summer temperatures and
winter temperatures rarely
approaching freezing
 Some rainfall in the form of summer
showers; many shrubs and annual
species bloom either in the summer
or in the fall
© Project SOUND
https://en.wikipedia.org/wiki/Anza-Borrego_Desert_State_Park
http://geogypsytraveler.com/category/places-ive-been/united-
states/california/anza-borrego-california/page/2/

100. Creosote bush
scrub
 Low species diversity
 Characteristic species: Larrea
tridentata (Creosote bush) and
Ambrosia dumosa (Burrobush)
 While dominated by woody
shrubs, both herbaceous annuals
and perennials are well
represented
 Well-spaced shrubs [due
combination of factors: moisture;
root characteristics; vegetative
reproduction; phytotoxins]
 Shrub size dependent on available
moisture
© Project SOUND
http://www.marriedtoplants.com/hodgepodge/visit-anza-borrego-desert-see-wildflower-
super-bloom/
http://home.sandiego.edu/~pkemp/Bio112-Desert.html

101. Creosote-bursage flats: CA/NV
 A vast expanse of seemingly uniform-
height shrubs on desert flats.
 Low: below 4,000 feet
 Gentle slopes, bajadas
 annual precipitation is 6 inches or
less and unreliable
 Temperature extremes: > 110ºF
during summer, 25ºF during winter.
© Project SOUND
http://www.birdandhike.com/Veg/HabType/Creo-Bur/_Creo-Bur.htm

102. © Project SOUND
*Creosote bush – Larrea tridentata
©2005 Steve Matson

103. © Project SOUND
*Creosote bush – Larrea tridentata
http://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=30255
Charles Webber © California Academy of Sciences
©1995 Saint Mary's College of California
 Throughout the Mojave, Sonoran, and Chihuahuan
deserts - the most characteristic species of the
hot deserts of North America.
 Commonly grows on bajadas, gentle slopes, valley
floors, sand dunes, and in arroyos to 5,000 feet
 Occurs on calcareous, sandy, and alluvial soils that
are often underlain by a caliche hardpan

104. © Project SOUND
Creosotebush reflects its surroundings
 Size:
 3-8+ ft tall (size depends on
available water)
 3-8 ft wide
 Growth form:
 Evergreen woody shrub; slow to
moderate growth rate
 Many slender, irregular branches
 Form: irregularly mounded
 Foliage:
 Leaves simple, small, sticky leaves
 Foliage very aromatic when wet –
the ‘smell of a desert storm’
 Allelopathy?
 Roots: shallow taproot and laterals
©1992 Gary A. Monroe
©2008 Thomas Stoughton

105. Creostebush adaptations to harsh desert
conditions: many
 Size/growth:
 Take advantage of cool, moist years for
growth, germination
 Can be near-dormant
 Foliage:
 Small leaves
 Thick, with waxy, protective coating
 Can dry down significantly
 Root:
 Taproot can go as far as possible
 Laterals; take advantage of any rain
 Plant spacing: root and leaf-derived
allopathy & germination inhibition
© Project SOUND
Not the first choice for insect
& other herbivores

106. © Project SOUND
Flowers attract pollinators
 Blooms: after rains – Mar-Apr and
then again Aug-Sep with summer
monsoons/irrigation.
 Flowers:
 Small (1/4-1/2 in) – but many;
plants appear yellow in good
bloom season
 Bright yellow petals and
prominent stamen/pistils
 Excellent pollinator plant
 Seeds: in fuzzy capsule; important
food source for desert birds and
animals
 Vegetative reproduction:
important for longevity
©2002 Charles E. Jones
©2005 Steve Matson

107. © Project SOUND
One tough shrub!!!
 Soils:
 Texture: well-drained; if not, berm
 pH: any local
 Can tolerate soils with hardpan
 Light: full sun; tolerates heat
 Water:
 Winter: adequate (6-8 inches)
 Summer: extremely drought
tolerant; looks better with
occasional summer water (once a
month; Water Zone 1-2 probably
optimal) – active even in drought
 Fertilizer: none; likes poor soils
 Other:
 Don’t over-water; needs some
stress for good shape
 Prune as needed/desired
©2008 Neal Kramer
This plant can be kept ‘natural’
or shaped extensively (if
desired) – even used as a
small ‘tree’

108. © Project SOUND
Adaptable shrub
 Foundation or background shrub
 ‘Tree’ or pruned hedge/hedgerow
 Excellent all-round habitat plant;
shelter, food, perches, even nesting
 Scented garden; desert garden
http://www.public.asu.edu/~camartin/plants/Plant%20html%20files/larreatride
ntata.html
http://www.plantmaster.com/gardens/reverse.php?plantnum=254

109. The medicinal side of
Creosotebush
 Known commonly as ‘chaparral’ (nothing to
do with CA Chaparral plant community)
 Long history of medicinal use:
 Twigs and leaves may be boiled as tea,
steamed, pounded into a powder, pressed
into a poultice, or heated into an infusion.
 Used mostly to cause vomiting and
externally to treat wounds, sores, skin
ailments or rheumatism
 Sometimes touted as a ‘cure-all’
 The United States Food and Drug
Administration has issued warnings about
the health hazards of ingesting
chaparral or using it as an internal
medicine, and discourages its use. In
2005, Health Canada issued a warning to
consumers to avoid using the leaves of
Larrea species because of the risk of
damage to the liver and kidneys.
© Project SOUNDhttps://www.amazon.com/Arizona-Natural-Chaparral-Tridentata-
Capsules/dp/B0001OP4JC
https://thebalmlady.com/listing/248553903/creosote-skin-salve-chaparral-healing

110. Traveling south, we notice mountains
ringing the central lowlands
 The terrain consists mostly of
broad, flat valleys with widely-
scattered, small mountain ranges of
almost barren rock.
 Mountain ranges:
 Around the east side of Joshua Tree
NP in the north (the Orocopia
Mountains, the Chuckwalla Mountains,
the Coxcomb Mountains)
 In Anza-Borrego Desert State Park
 The Colorado River ranges
(Chemehuevis, Whipples, Big Marias).
© Project SOUND
https://commons.wikimedia.org/wiki/File:Wpdms_shdrlfi020l
_little_san_bernardino_mountains.jpg

111. Orocopia Mountains
Wilderness Area
 To the east of the Salton Sea
 Used area to train astronauts for moon landings there
© Project SOUND
https://www.wikiloc.com/hiking-trails/california-orocopia-mountains-red-canyon-wash-
loop-2-2466351/photo-956522

112. Orocopia Mountains
Wilderness Area
 Designated 1994; BLM managed
 51,289 acres
 Despite the harshness of the
climate, you can see a wide
variety of plants and animals
adapted to life in the desert
 Some endemic plant species
 fossilized remains of prehistoric
animals resembling horses,
camels, and deer
© Project SOUND
http://michaeldorausch.com/orocopia-mountains-wilderness-wildflowers/

113. Chuckwalla Mountains & Valley
 Just east of the Oricopa Mountains
 Have some interesting reptile species
© Project SOUND
https://eagleviewlotsandland.com/chuckwalla/

114. Little Chuckwalla
Mountains Wilderness
 Ocotillo, cholla, yucca,
nolina, and barrel cactus
cloak the landscape;
Ironwood line the washes.
 The occurrence of Munz
cholla (the largest known
cholla), found only here and
in the Chocolate Mountains,
is only one of a number of
rare plants found in this
wilderness area.
© Project SOUND
http://rvsueandcrew.net/a-boondock-in-the-chuckwalla-mountains-wilderness/
https://www.summitpost.org/black-butte-chuckwalla-mountains/994130

115. Why visit the Orocopa & Chuckwalla
Mountains
 Wonderful spring wildflowers in a
good year
 Interesting (including rare) plants
adapted to a very harsh environment
 Traces of fossil and Native
Californian life
© Project SOUND
http://www.basinandrangewatch.org/ChuckwallaValley1.html
http://www.basinandrangewatch.org/ChuckwallaValley1.html

116. Desert wildflowers are a sight to behold
© Project SOUND

117. Unfortunately, seeds are not available for
many desert annuals
 I’ve updated the Plants &
Seed Source list to include
some Desert resources
 List available on Mother
Nature’s Backyard blog
© Project SOUND
https://shop.nativeseeds.org/products/sc009

118. © Project SOUND
*Jones’ blazingstar – Mentzelia jonesii

119.  Desert Mountains, White and Inyo Mountains,
Sierra Nevada East, Mojave Desert, Sonoran
Desert to AZ, NV
 Sandy to rocky washes, fans, or flats,
creosote-bush scrub, Joshua-tree or saguaro
woodlands to about 5000 ft.
© Project SOUND
*Jones’ blazingstar – Mentzelia jonesii
http://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=33248

120. The Loasa family (Loasaceae)
 Family of 15–20 genera and about 200–
260 species
 Unusual floral morphology –most quite
beautiful
 Many have painful stinging hairs
 Native to the Americas and Africa;
most are tropical
 Mentzelia is one of three genera native
to CA – some w/ no stinging hairs!
 Difficult to classify, even with DNA
© Project SOUND

121. California Mentzelias
 32 CA native species
 15% are perennials – rest annuals
 60% are strictly desert species;
mostly to Creosote bush scub
 Many of the rest are from
higher elevations – a few from
local mountains or coastal
 Some are very rare and locally
endemic
 Seeds available for very few
© Project SOUND
©2012 Aaron Arthur
©2010 Jasmine J. Watts

122. © Project SOUND
Jones’ blazingstar is a desert annual
 Size:
 1-2 ft tall
 1-2 ft wide
 Growth form:
 Annual wildflower
 Erect, branching form
 Slender stems often pink-
tinged, hairless
 Foliage:
 Leaves basal & a few on stems
 Deeply lobed, usually hairy
 Leaf shape linear to lanceolate

123. © Project SOUND
Satiny yellow flowers
 Blooms: after winter rains
(Mar-May)
 Flowers:
 Mostly at tips of sender
branches – appear to float
 Five bright yellow, satiny
petals, often with orange at
base
 Many slender stamens
 Sweet, charming, lovely
 Seeds: in S-shaped, dry
capsule; easy to collect & save
http://www.answers.com/topic/dudleya

124. © Project SOUND
Plant Requirements  Soils:
 Texture: adaptable; sandy or
rocky soils in desert
 pH: any local
 Light:
 Full sun to light shade
 Water:
 Winter: adequate for growth
and development
 Summer: taper off water as
blooming slows
 Fertilizer: none; likes poor soils
 Other: inorganic (gravel) mulch –
or none at all

125. © Project SOUND
Gardening with annual
Mentzelias
 Accent plant; place where people
can enjoy it
 Desert gardens – or just about
any other garden with flowers
 As an attractive pot plant
http://swbiodiversity.org/seinet/taxa/index.php?taxon=2514
https://alchetron.com/Mentzelia
https://www.pinterest.com/pin/719450109193192347/

126. Desert playas present some unique
challenges to Sonoran Desert plants
© Project SOUND
http://www.rediscoveringthegoldenstate.com/colorado-desert/

127. Characteristics of CA Deserts playas
important for gardeners
 Soil texture: heavy clay; slower draining often with hardpan
 Soil pH: alkali; often salty
 Soil moisture: extremes
© Project SOUND

128. Saltbush/Alkalai
(Shadscale) Scrub
 Occurs in California throughout the
Mojave Desert and parts of the
Colorado & Great Basin Deserts
 Common in California deserts, but
are scattered and usually associated
with dry lakes, playas and flood
plains of rivers. Playa edge plants.
 Predominence of shrubby saltbushes
(allscale, desert holly, fourwing
saltbush, other saltbushes),
shadscale, & limited others
 Some too specialized for common
garden use: we’ll consider a few later
this year.
© Project SOUND
https://www.laspilitas.com/nature-of-california/plants/108--atriplex-polycarpa

129. Alkali Sink community
 Dry lakebed margins, hummocks,
playas perched above current
drainages, seeps
 Adapted to high alkalinity and salinity
 Not an easy or attractive plant
community for our area (except for
old brackish wetland areas)
© Project SOUND

130. Colorado Desert dunes also create a
unique habitat and flora
© Project SOUND
Not every native plant can succeed in sand!
https://www.trover.com/discoveries/wall?d=1CEmg

131. Some local gardens have sandy soils
© Project SOUND
So some dune plants might work, if other conditions are met

132. North Algodones Dunes Wilderness
(Imperial Sand Dunes Recreation Area)
© Project SOUND
https://www.trover.com/d/1CEmg-north-algodones-dunes-wilderness-area-imperial-county-california

133. North Algodones Dunes Wilderness
(Imperial Sand Dunes Recreation Area)
 Designated 1994
 25,895 acres; one of the largest dune
complexes in North America.
 managed by the Bureau of Land
Management.
 Primary dunes (west): larger, coarse
sands, more stationary
 Secondary dunes (east): shorter dunes,
finer texture, mobile, intersperse with
other habitats (basins, flats, arroyos)
© Project SOUND
http://www.wilderness.net/NWPS/enlargeAndDetails?id=3401
http://sand.xboltz.net/algodones.html

134. The secondary dunes are more
interesting from a gardening standpoint
 Interspersed with basins or flats, with mesquite, smoke
tree, ironwood, paloverde, and desert willows.
© Project SOUND

135. Colorado Desert plant communities you
can see at Algodones Dunes
 Creosote Bush Scrub
 Psammophytic scrub
 Microphyll woodland
 Open Dunes
© Project SOUND
Microphyll woodland Open Dunes
https://sites.google.com/a/ucdavis.edu/algodones/database/plants
Psammophytic scrub

136. Desert Psammophytic Scrub (Desert
Dune Sand Plant)
 Plants restricted entirely/largely to active
dune areas: Ammobroma sonorae, Astragalus
magdalenae peirsonii, Croton wigginsii,
Ephedra trifurca, Eriogonum deserticola,
Helianthus niveus tephrodes, and Palafoxia
arida gigantea (M. E. Jones) Turner & Morris
(P. linearis gigantea) on the Algodones Dunes.
 Other more widely distributed but
characteristic psammophytes include
Abronia villosa, Astragalus lentiginosus
borreganus, Croton californicus mohavensis,
Dicoria canescens, Geraea canescens,
Hesperocallis undulata, Oenothera
deltoides, Mentzelia longiloba, Peta/onyx
thurberi, Rumex hymenosepalus, and Tiquilia
Pers. (Coldenia) spp.
 In years with good precipitation some dune
areas resemble a desert grassland
© Project SOUND
http://granite.ucnrs.net/?page_id=877

137. Coping with shifting
sands
 Annuals and perennials: settle in
areas with less movement (arroyos,
depressions, areas outside active dunes)
[pink sand verbena (Abronia villosa),
white dune evening-primrose (Oenothera
deltoides) and yellow sunflower (Geraea
canescens)]
 Deep-rooted shrubs anchor the
dunes and create habitat for reptiles
and birds [mesquite (Prosopis
glandulosa), creosote bush (Larrea
tridentata) and desert buckwheat
(Eriogonum deserticola)]
 Larger shrubs grow in basins or flats
[mesquite, smoke tree, ironwood, palo
verde and desert willow trees]
© Project SOUND
https://en.wikipedia.org/wiki/Algodones_Dunes
https://www.desertusa.com/OHV/du_algodones.html

138. Dune scrub annuals, perennials and bulbs
can work well in local gardens
© Project SOUND
https://www.laspilitas.com/nature-of-california/plants/6--abronia-villosa-villosa
Sand verbena (Abrona villosa) thrives in sandy coastal gardens

139. © Project SOUND
*Leafy prickly poppy – Argemone corymbosa
© by Curtis Clark

140.  Desert mountains, Mojave and Sonoran
Deserts of CA, AZ;
 Dry flats and slopes, stabilized dunes,
washes, sandy or granitic soil in Creosote
Bush Scrub, 1000-4000 ft. elevation.
 Katharine Brandegee,
© Project SOUND
*Leafy prickly poppy – Argemone corymbosa
©2006 J. G. Riend ©2006 J. G. Riend
http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=233500128

141. © Project SOUND
Prickly poppy: comes well-armed
 Size:
 1-3 ft tall
 1-2 ft wide (adds new stems)
 Growth form:
 Herbaceous perennial
 Upright habit; stout stem is
armed
 Foliage:
 Leaves pale to blue-green
 Succulent, lance=shaped to
oval and well-armed
(particularly beneath)
 Margins toothed
 Orange sap (don’t ingest)
©2014 Neal Kramer

142. © Project SOUND
Flowers are fantastic
 Blooms: in spring - usually April-May
 Flowers:
 Fairly large: ~ 2-4 inches
 Looks like Matilija Poppy
 4 overlapping, crinkled white
petals
 Lots of yellow-orange stamens
 Very showy – be the envy of your
friends
 Seeds:
 Spiky seedpod – really unique
 Vegetative reproduction: adds new
shoots each year
©2014 Neal Kramer
©2010 Michelle Cloud-Hughes

143. © Project SOUND
Plant Requirements  Soils:
 Texture: any well-drained;
less particular than some
desert species
 pH: any local
 Light: full sun
 Water:
 Winter: at least 6-8 inches
 Summer: little to no water
once established (Water
Zone 1 or 1-2)
 Fertilizer: none; likes poor soils;
inorganic or no mulch
 Other: cut back very carefully
(wear gloves) after flowering or
seed set
©2017 Jean Pawek

144. © Project SOUND
Prickly poppy
 In a pollinator garden
 As an accent in a desert-themed
or rock garden
 In a large container
 Be sure to plant away from
traffic (unless you mean to do so)
©2014 Neal Kramer
http://www.laspilitas.com/nature-of-california/plants/3446--argemone-corymbosa https://www.flickr.com/photos/128459319@N04/17156276159

145. Characteristics of CA Desert Dune plants
important for gardeners
 Soil texture: generally sandy, well-drained
 Soil fertility/organic content: generally vary low
 Water table/soil moisture: generally dry but depends on
drainage
© Project SOUND

146. Thus far we haven’t even talked about cacti
© Project SOUND
Cholla Cactus Garden – Joshua Tree National Monument

147. Stem-succulent
(Cactus) Scrub
 Open, spinescent, succulent-
stemmed scrub; small to tree-like
 Far better developed in AZ and
Baja; can be seen from Pinto and
Eagle Mtns. of Joshua Tree National
Monument south
 On bajadas and other gentle slopes,
with fine soil texture and mostly
facing south, and in well-watered
sandy arroyos
 Colorado Desert species are limited:
Opuntia bigelovii and other chollas,
various species of Echinocereus,
Mammillaria, and Coryphantha
clearly dominant; other shrubs may
be present.
© Project SOUND
https://modernhiker.com/hike/blue-angels-peak/
Cholla Cactus Garden - Pinto Basin,
Joshua Tree

148. Stem-succulents present drainage challenges in
local gardens – particularly in el Niño years
© Project SOUND

149. But they can make glorious accent plants…
© Project SOUND

150. © Project SOUND
*Ocatillo – Fouquieria splendens
http://tucson.com/lifestyles/things-to-know-about-ocotillos/collection_c8ef74d8-276d-
11e6-b9ba-134c84ea28aa.html#1

151. © Project SOUND
*Ocatillo – Fouquieria splendens
©2004 Heath McAllister
©2008 Gary A. Monroe
http://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=77256
 Sonoran (Colorado) Desert from CA to Texas,
central Mexico, Baja California
 In CA: Anza-Borrego and south; Chuckwalla and
Chocolate Mountains
 Dry, generally rocky soils, < 700 m.
 Creosote bush scrub

152. We’ll consider some strategies for using
stem-succulent accents in November
© Project SOUND
https://www.springspreserve.org/explore/botanical-garden.html

153. Chocolate Mountains
© Project SOUND
https://southwestphotojournal.com/2012/01/24/little-picacho-wilderness-opens-door-to-
california-chocolate-mountains-and-winter-adventure/

154. Chocolate Mountains: Little Picacho
Wilderness; Indian Pass Wilderness
 Riverside & Imperial
Counties
 Form the northeast
boundary of the Salton
Trough, extending from the
Orocopia Mountains to the
Colorado River valley
 Warm & dry : typically 4-6
in.; mean annual temperature
is about 60 °F to 75 °F
© Project SOUND
https://en.wikipedia.org/wiki/Chocolate_Mountains
 Plant communities of note:
 Creosote bush–white bursage community
 Stem-succulent (Cactus) Scrub
 Desert Microphyll Woodland

155. Desert riparian woodland (Colorado Desert)
 Along permanent water sources
(mostly rivers); look similar to local
riparian woodlands
 May include typical riparan tree
species (Willows/Cottonwoods;
Baccharis; ) as well as other large
shrubs and trees.
 Often a well-developed understory:
 Riparian species: cattails; rushes
 Other perennials & grass-like
plants
 Trees and larger shrubs remain green
except in winter (winter deciduous
types) or very bad drought
© Project SOUND
http://tommysbirdingexpeditions.blogspot.com/2014/03/two-
location-lifers-in-one-day.html
http://onthegrapevine.blogspot.com/2006/11/

156. Desert Microphyll Woodland
 Along seasonal desert waterways, arroyos
of the Colorado Desert [Sonoran Desert in
general]
 Stored runoff water stored under and along
the sandy or gravelly beds supports a rich
shrubby flora
 Larger trees/shrubs may be dormant in dry
years – but they’re still access ground
water
 Warmer round-the-year temperatures and
perhaps other factors support an open to
sometimes dense woodland of small (to 5 m),
microphyllous trees, especially Fabaceae.
 Smaller shrubs or perennials also
conspicuous along the arroyo margins
© Project SOUND
http://home.sandiego.edu/~pkemp/Bio112-Desert.html

157. Desert Microphyll
Woodland
 Very important animal habitat;
supports diverse array of
insects, birds, animals
 Supports interesting group of
plants that cope with extremes
of soil moisture
 May become an increasingly
important source of garden
trees and shrubs for L.A. Basin
– much more next month
© Project SOUND
http://www.basinandrangewatch.org/Blythe-Sep.html

158. © Project SOUND
*Desert senna – Senna armata
©1992 Gary A. Monroe

159.  Desert Mountains, Mojave & Sonoran
Deserts of CA, AZ, NV & Baja CA
 Common in sandy and gravelly washes and
open flats in Creosote bush scrub, Desert
microphyll woodland, below 3000'.
© Project SOUND
*Desert senna – Senna armata
http://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=44131
©2014 Neal Kramer
https://www.laspilitas.com/nature-of-california/plants/135--cassia-armata

160. © Project SOUND
Desert senna: medium Sonoran pea-shrub
 Size:
 3-5 ft tall
 4-6 ft wide
 Growth form:
 Mounded to sprawling sub-shrub
 Densely branched
 Drought deciduous;
stems/branches can
photosynthesize or become
dormant
 Foliage:
 Leaves small and simple; often no
leaves
 Roots: deep & shallow
©2004 Heath McAllister
©2017 Jean Pawek

161. © Project SOUND
Flowers are fantastic
 Blooms: in spring - usually April-
May in S. CA
 Flowers:
 Golden yellow or slightly
orange
 Small clusters of flowers at
ends of branches (mostly)
 Flowers typical shape for
Senna (Cassia); 5 petals with
somewhat pea-like shape
 Vegetative reproduction:
 Sprouting from stem
http://www.answers.com/topic/dudleya©1992 Gary A. Monroe
©2010 Michelle Cloud-Hughes

162. Seed starting: desert legumes
 Let seeds mature on the plant (need
dry heat); use relatively new seed if
possible
 Soften hard seed coat (may also have
waxy coating) by one of following:
 Pouring boiling water over seeds – let
cool and sit overnight
 Soaking 24 hours; change water 3 times
 Nicking seeds
 May need to germinate in wet paper
towel or coffee filter in sealed plastic
bag (room temp)
 Plant several seeds in 1-gal pot with
well-drained medium;
© Project SOUND
https://seedsofsuccess.smugmug.com/Bureau-of-Land-
Management/BLM-NV052B/i-c7hzjtr
perhaps 30% will grow

163. © Project SOUND
Plant Requirements  Soils:
 Texture: very well-drained –
sandy or rocky; may be able to
get by with berming
 pH: any local
 Light: full sun
 Water:
 Winter: needs at least 6 inches
 Summer: no to very occasional –
Water Zone 1 to 1-2 – after
first year
 Fertilizer: none; likes poor soils;
no mulch or inorganic mulch
 Other: tip-prune or prune lightly in
fall for fuller shape
©2004 Michelle Cloud-Hughes

164. © Project SOUND
Interesting drought
tolerant habitat
Gerald and Buff Corsi © California Academy of Sciences
http://benkolstad.net/?p=7779
 Desert and other water-wise
gardens; good accent plant
 Larval habitat for Cloudless
Sulphur
 Medicinal: laxative

165. Why all the Peas in the Sonoran Desert?
Come next month to find out
© Project SOUND
http://www.plantmaster.com/gardens/eplant.php?plantnum=265

166. Why visit the Colorado Desert (when
we’re focusing on ‘Gardens that Heal’)?
© Project SOUND
https://borregohiking.com/hiking/2011_fish_creek_wash_north_fork.html

167. Deserts/desert plants can play an
important role in nature healing
 Getting out in quiet, remote places
– even for a day trip – can be very
therapeutic
 In our gardens, desert plants can:
 Add just enough novelty to hit the
sweet-spot between too much and
too little stimulation
 Inspire us to learn more about our
California home
 Force us to try a new challenge
 Stimulate us to take positive
action: mental and physical
© Project SOUND

168. Challenges to the unique Colorado Desert
flora/fauna: the same as for all California habitats
 Human effects
 Growth & development/
habitat loss
 Agriculture
 Invasive species
 Ground water issues
 Recreation/OHV
 Climate change
© Project SOUND
https://www.alltrails.com/parks/us/california/north-algodones-dunes-wilderness
Taking action to better our environment is healthy for us
as well (yes – that’s evidence-based)

169. Check the wildflower hotlines and go visit a
local desert area – for your health!
© Project SOUND
http://www.theabf.org/wildflowers