resembling a parasol (plate 7- 20). Leaves are whitish
underneath and frequently insect- damaged. Dried,
shriveled cecropia leaves that have dropped from the
trees are a common roadside feature in the tropics.
Some cecropias have stilt roots, but the trees do not
form buttresses.
Cecropias typically occur in areas of large light gaps
or secondary growth, though some persist in second-
growth forests. Pioneer colonizing species, cecropias
are well adapted to grow quickly when light becomes
abundant.
Seeds remain viable in the soil for about a year and
germinate when a gap is created. Cecropia seeds are
sometimes abundant in the seed bank. An average of 73
seeds per 1 m^2 (10.75 ft^2 ) were present on one study site
in Suriname. Because there are so many viable seeds
present, cecropias sometimes completely cover a newly
abandoned field or open area. They line roadsides and
are abundant along forest edges and stream banks.
Cecropias are effective colonizers because their seeds
have a long residence time in the soil and accumulate
there over time. Once germinated cecropias grow
quickly, up to 2.5 m (8.2 ft) or more in a year. They
are, however, generally short- lived, surviving to about
30 years, though some persist longer if established in
the canopy. One limit to colonization by cecropia is
recruitment from distant seed sources, such as could
occur when there has been much forest fragmentation
(chapter 16). Without nearby adult trees, seed dispersal
is limited.
Cecropias are moderate in size, rarely exceeding 25 m
(80 ft) in height, though some emergent cecropias reach
40 m (130 ft). They are intolerant of shade, their success
hinging on their ability to quickly grow above the myriad
vines and herbs competing with them for space. To this
end, cecropias, like many pioneer tree species, have a very
simple branching pattern and leaves that hang loosely
downward. Vines attempting to grow over a developing
cecropia can easily be blown off by wind and possibly
deterred by Azteca ants (more on these below), though
I have seen many small cecropias that were vine- covered.
Cecropias have hollow stems, a possible adaptation for
rapid growth in response to competition for light, as this
structure permits the tree to devote energy to growing tall
rather than to the production of wood.
Cecropias have separate male and female trees and
are well adapted for mass reproductive efforts. A single
female tree can produce more than 900,000 seeds every
time it fruits, and it can fruit often. The base of eachPlate 7- 21. Large birds such as aracaris (a form of toucan) are
among the many that feed on cecropia fruits. Photo by John
Kricher.Plate 7- 22. This dried cecropia leaf forms habitat for spiders
and insects, which tuck into its curled edges. Photo by John
Kricher.Plate 7- 23. The Worm- eating Warbler, a North American
migrant, specializes in probing dried, fallen cecropia leaves
(as well as large leaves from other species) while on its
Neotropical wintering grounds. Photo by John Kricher.chapter 7 if a tree falls . . . rain forest disturbance dynamics 109