Pittocaulon
(Senecio) praecox
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This
species has the widest range of the genus, and is photographed here on
the lava surrounding the Instituto de Biología. This photograph
was taken in January.
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Some species of Pittocaulon
are popularly called "palo loco" or "crazy tree",
because
they flower at the very end of the dry season when most other plants
are suffering
the effects of drought. This photograph was taken in March. |
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This
photograph
and the one below were taken in the northern part of the state of
Morelos,
at nearly 2000 meters above sea level. |
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The stems of Pittocaulon
are very thick and fork into two, three, or four branches after flowering, leading to the
strange
architecture that can be seen in this image. |
Pittocaulon
(Senecio)
velatum ssp. velatum |
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After P.
praecox, the most widespread
species
is P. velatum. The subspecies velatum is found in
western and
central Mexico. In this image from Jalisco, a lone individual grows up
above
the edge of a steep cliff. |
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Pittocaulon
praecox
branches after flowering. It seems likely that the other species of Pittocaulon
branch in the same way. Thus this individual of P. velatum velatum
has probably flowered several times. |
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Individuals of P.
velatum ssp. velatum
can become enormous, growing as members of low tropical deciduous
forest.
This large specimen was photographed in northern Oaxaca. A younger
individual
is at left. |
Pittocaulon
(Senecio) velatum ssp. tzimolensis |
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This subspecies
is
restricted to extreme southern Mexico. Like most Pittocaulon, it
grows
on rock, often in very steep situations such as this canyon in
Chiapas. |
Pittocaulon
(Senecio)
filare |
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This species is
known
only from a single small area in the state of Colima. It is smaller
than P. praecox and has densely wooly leaves. Like its larger
cousin, P. filare has
bright yellow flower heads,
of which the bases remain for some time after the seeds are shed. |
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The pith of all Pittocaulon
species is often divided into horizontal strata. These strata
appear to expand when water is abundant and shrink as the stored water
is
used through the dry season. This photo was taken at the end of the dry
season. |
Pittocaulon
(Senecio)
bombycophole |
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Only found in a
few
places in Michoacán and Guerrero states, this species branches
sparingly
and has a relatively thick trunk and branches. The leaves, like those
of P. filare, are covered with white hairs. The population
shown
here, from Michoacán, consisted of less than a dozen
plants. |
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This species
occurs
in a remarkable number of situations: The plants at left are growing on
exposed
bare limestone. The plant at bottom left is shown growing next to a
large
wild fig tree (Ficus petiolaris) in open tropical dry forest.
Finally,
the individuals below center was found growing in the understory of
dense
deciduous forest. The flowers of P. bombycophole are shown at
bottom
right. |
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Pittocaulon
(Senecio) hintonii |
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This
remarkable species is restricted to a few localities in
Michoacán and Colima states. ssp. Pittocaulon hintonii ssp. hintonii, shown here, is only known
from southwestern Michoacán. This species tends to branch
relatively little, forming small treelets in pockets of soil on
boulders. This photo and the next were taken in August, during the
rainy season.
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Pittocaulon hintonii ssp. cerrograndensis is from the Sierra
de Manantlán to the west of the range of the type subspecies.
This subspecies tends to grow in more sheltered areas and is often
shorter and more branched than ssp. hintonii.
With its mop of floppy, somewhat hairy leaves on broomstick like stems,
this species is a striking element of the beautiful mid-elevation
tropical dry forests of the Sierra de Manantlán.
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