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.
|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.|
|This photograph and the one below were taken in the northern part of the state of Morelos, at nearly 2000 meters above sea level.||
|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|
|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.|
|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.|
||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||
|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|
|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.|
|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|
|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.|
|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.|
|Pittocaulon (Senecio) hintonii|
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
|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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