In arid northwestern Yucatan's scrubby forest you do not see the smallish tree shown at the right with its straight, bamboo-like stem and oversized, umbrella-like leaves. That's because this tree likes more rain than falls in the northwest. The farther east and south you travel in the Yucatan, the more of this tree you see, especially in disturbed habitats such as along roadsides.
This is a Cecropia, of which two species occur in the Yucatan: Cecropia peltata, and C. obtusifolia. The one in the picture is C. peltata.
Cecropias come in male or female trees -- they're dioecious. The best way to distinguish C. peltata from C. obtusifolia is by looking at their female flower spikes. The ones shown below are C. peltata and are about four inches long (10cm). If they were longer and more slender they'd be C. obtusifolia.
A cluster of spikes of male flowers of C. peltata is shown below:
Cecropia tree stems are hollow and segmented, with some segments bearing holes serving as doors for ants who live in the stems. If a large herbivore comes eating the tree, the biting ants may drive it away. Not only do Cecropia flowers produce sweet nectar that attracts ants but also the tree's mature female spikes are sweet and succulent, and eaten by birds and mammals. Historically the Maya have considered the spikes an emergency food.
Ceropia peltata enjoys high repute as a medicinal plant. The book Las Plantas Medicinales de México describes it as useful against obesity, asthma, liver ailments and diabetes. The trunk's outer layer contains cecropina, considered to be a powerful heart tonic and diuretic. Once when I was exploring Mexico City's enormous Merced market I asked a big-time medicinal herb dealer which of all the plants he knew he'd take with him if he had to go live on an island with just one medicinal plant. "¡Guarumo!" he replied without batting an eye.