[slow, quiet music fades in]
This is what the land's been waiting for.
Desert organisms seem to herald the arrival of spring wildflowers with great anticipation.
They're a food source for animals, a means of reproduction for plants,
a burst of energy for the normally harsh landscape.
But these blooms are the result of complex environmental mechanisms,
formulated behind the scenes by unique conditions and hidden processes.
[slow music]
The Colorado Desert is an ecosystem on the edge, straddling the borders of two deserts,
the Mojave and the Sonoran.
As such, it shares many features of both, and in doing so, becomes unlike either.
Its low-elevation canyons and basins are shielded from coastal air by Southern California's mountains,
which force precipitation and leave the air warm and dry as it descends into the desert below. The result is very little rainfall, and without this reliable source of water, it's a wonder that the desert can support significant plant life at all, let alone a mass flowering event.
But these spring blooms still occur, which means that the fuel for engineering desert wildflowers
must come from another source.
While the Colorado Desert is blocked from receiving coastal rains,
it's left exposed on another front. Weather approaching from the south has an unimpeded path for reaching the desert,
but the kind of weather that makes this journey is unlike the kind that would enter from the coast.
This reality, along with the geographic placement, sets the stage for extreme environmental conditions,
and ultimately, rare ecological events like the spring wildflower bloom.
The story of each spring wildflower bloom begins the year prior.
In August and September, late summer storms climb up from the south and bring heavy rainfall
to the Colorado Desert.
This is the same time that annual plants will germinate, nearly six months before an expected bloom.
The dramatic, unpredictable nature of the late summer storms means that the wildflower blooms are
equally unpredictable, and may sometimes not emerge as expected.
When the plants' water requirements are satisfied,
temperatures in the winter will dictate the timing of when the flowering plants escape the depths of the desert soil.
Deserts like the Colorado endure huge temperature fluctuations due to heat radiating back into the atmosphere,
and flowers won't emerge as long as the desert remains cold.
Much of the region between the Mojave and the Sonoran lies at a low elevation,
which means warmer temperatures earlier in the year, and earlier yields of wildflowers.
With so many factors in play in determining the emergence of the wildflowers,
It's a near-miracle every time such a bloom takes place.
But this miracle is something that the Colorado Desert has come to rely on,
as the flowers are an important resource for many desert species.
The caterpillars of some butterfly species are only able to feed on specific types of wildflowers,
as thus rely on them exclusively during one of the most critical stages of their life cycle.
[slow music]
The annual plants, of course, must rely on the flowers for pollination in order to
set the stage for another bloom next year.
The color of each flower corresponds to the pollinator with which it's ecologically tied.
The yellow flowers of the Desert Dandelion attract insect pollinators,
while flowers with red hues traditionally share a closer association with birds.
The seeds of desert wildflowers, the result of the plants' brief emergence and pollination,
will lie dormant for months, escaping the harsh summer temperatures, which often exceed 100 degrees Farenheit.
These seeds will begin anew the annual cycle, awaiting storms later in the year and the chance to
emerge the following spring.
The life cycle of desert wildflowers is an utterly delicate process,
but based on tumultuous, dramatic, and unpredictable environmental conditions.
How it continues to perpetuate is an astonishing feat that virtually defies explanation,
yet sustains the enigmatic Colorado Desert year to year as one of western North America's most unique and extraordinary ecosystems.
[slow music]