 Annual
Precipitation:
5-10 inches of precipitation
Common Animals
Ladder-backed woodpecker, scorpions, lizards, snakes, small
mammals, butterflies and moths
Common Plants
Joshua Tree
(Yucca brevifolia), Buckwheat(Eriogonum
species, E.
fasciculatum var. polifolium), Apache
Plume (Fallugia paradoxa), Desert
Alyssum (Lepidium fremontii), Juniper
(Juniperus spp.),
Soil and climate notes:
Generally sandy to sandy loam soils rapidly being converted by
annual European grasses. pH is near neutral to alkaline(7.2-7.9)
This community is under siege by Bromus species. When Bromus
(small weedy foxtail type grasses) invades, the site is much more
fire prone. 5000-10000 acre fires burn in an area that used to
never see fire. Fire favors more Bromus.
The Joshua Tree Woodland extends along the eastern edge of the
Sierra Nevada, up into south Nevada and Northeastern Arizona and
basically defines the edges of the Mojave Desert.
 The
soils in the Joshua Tree Woodland are usually a slightly acidic
sandy loam. Rainfall is commonly higher than the lower areas of
the Mojave desert and can range from seven to twelve (8-10
commonly) inches annually. The climate is pleasant much of the
year, but because the elevation is 2500-5000 feet, the winter
winds can sometimes blow through you. The lows are not that bad,
in a twenty year period a 0F or even lower may be experienced,
but it is only for a few hours. Then the wind picks up and the
daytime temperature may be in the 50's or even 70's. The wind
chill at 0F and 30 mile per hour winds is dangerous. The ground
doesn't freeze deeper than about an inch. This plant community
will commonly get a dusting of snow, rarely more than an inch or
two. You learn to wait until the sun comes up to wander outside;
pity the poor chump in the light sleeping bag.
 Summer
temperatures can be above 100F for eight months of the year, but
it is generally for only a few hours. It's dry heat, and there is
usually wind or a breeze. Night time temperatures in Joshua tree
areas usually cool off into the 70's or lower.(Unlike Creosote
Bush Scrub that can stay at 100 F all night; yuk!)
Cactus are not common in this plant community; odd shrubs and
wildflowers are. A clean, weed free, Joshua tree woodland is not
adapted to fire. When sheep or other grazing animals are
introduced they bring grasses. Bromus and other grasses spread
like wildfire when grazing is allowed; then this plant community
burns and is completely replaced by small dead (most of the time)
grass. If you live in this plant community, control the grass,
mustards and other flammable weeds.
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Joshua
Tree Woodland has a great deal of associated wildlife that you
might see if you look carefully as you walk either through the
wildflowers in spring, or bare ground the rest of the year. (If
you disturb any Joshua tree branches on the ground, make sure you
return them how you found them. This is usually the only place
for ground dwelling wildlife to hide from the wind, sun, and
predators.) The standing Joshua trees are the only place for
birds who want to nest off the ground except maybe the occasional
cliff.
 The
tightly packed dead leaves that line the trunks of these strange
trees are very important for insects, spider, lizards, and bird
to hide in. They probably also help block the wind that whistles
around them, helping slow desiccation of themselves and the
wildlife they harbor.
There's often a bird in the Joshua tree keeping a watchful eye
on you.

The enclosed areas are commonly Joshua Tree Woodland. Where
the rainfall drops below about seven inches, there is still
extreme summer heat, and the ground freezes in winter you'll find
Blackbrush (Coleogyne sp.). Blackbrush becomes dominant
and Joshua tree a minor element as the rainfall and/or
temperatures drop. Where the rainfall is less and the soil
doesn't freeze you'll move into a Creosote Bush Scrub plant
community. The Blackbrush plant community is fairly minor in
California.
To grow a Joshua Tree Woodland plant community, you need warm
to cool, and dry conditions, some Joshua
trees (Yucca brevifolia), sunny days, and lots of
elbow grease to keep out the weeds! If you are starting a new
garden and your yard is devoid of vegetation: to get started,
plant some California
Buckwheat (Eriogonum fasciculatum var. polifolium),
Gutierrez' Bush (Gutierrezia microcephala), Bur Sage (Ambrosia
dumosa), and Cotton -Thorn (Tetradymia glabrata). When they are
established (after one year), use these as nurse plants, and
plant the Joshua Tree (Yucca brevifolia) right next to
them (on the east side of them). Keep the soil bare of weeds
between the shrubs.
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