Associated Forest Cover
provided by Silvics of North America
As a secondary species, yagrumo hembra frequently invades forest
gaps or openings, roadsides, streamsides, and landslides in
moist, wet, and rain forest life zones of Puerto Rico. In the
Luquillo Mountains in eastern Puerto Rico and in the central
mountains it is widely distributed in the Lower Montane Forest,
Montane Rain Forest, and Elfin Woodland formations of these life
zones (1). In the Elfin Woodland it is short in stature and
gnarled, as are its associated species in this formation.
Yagrumo hembra is frequently associated with other secondary
species such as yagrumo macho (Didymopanax morototoni) and
guano (Ochroma pyramidale). The scattered presence of
this secondary species among species more characteristic of a
mature stand indicates that a disturbance, such as tree fall,
storm damage, or landslide, occurred at some time in the past.
Although initially dependent upon the size of the openings, pure
dense stands of yagrumo hembra, once established, may persist for
several years following the disturbance. The species may also be
found, in a dominant or codominant canopy position, associated
with primary species such as tabonuco (Dacryodes excelsa),
motillo (Sloanea berteriana), and ausubo (Manilkara
bidentata) in the Lower Montane Rain Forest; palo colorado
(Cyrilla racemiflora), caimitillo (Micropholis
chrysophylloides), and camasey jusillo (Calycogonium
squamulosum) in the Montane Rain Forest; and roble de sierra
(Tabebuia rigida) and nemoca (Ocotea spathulata) in
the Elfin Woodland.
Yagrumo hembra is less common in the hotter lowlands of Puerto
Rico. Here it may be an infrequent component of succession
primarily on the wetter sites following cultivation, associated
with the secondary species listed above as well as with many
introduced species. In the mogotes or limestone hills of
northwestern Puerto Rico, yagrumo hembra is associated with those
secondary species described previously as well as others such as
ucar (Bucida buceras), almacigo (Bursera simaruba),
and espino rubial (Zanthoxylum martinicense).
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Climate
provided by Silvics of North America
In Puerto Rico, yagrumo hembra is found most frequently in the
wetter life zones: Subtropical Moist Forest, with 990 to 2010 mm
(39 to 79 in) of precipitation annually; Subtropical Wet Forest,
with 2010 to 3990 mm (79 to 157 in); Subtropical Rain Forest,
with 3810 mm (150 in) and greater; Subtropical Lower Montane Rain
Forest, with 2010 to 3990 mm (79 to 157 in); and Subtropical
Lower Montane Wet Forest, with 3810 mm (150 in) and greater. Mean
annual temperatures in the lower montane life zones range from 12°
to 18° C (54° to 64° F), whereas in the lower
elevation life zones the range is from 18° to 24° C (64°
to 75° F). The species is rare or absent in the Subtropical
Dry Forest life zone.
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Damaging Agents
provided by Silvics of North America
In the seedling and sapling stages a
major cause of mortality is defoliation by the larvae of the
following: Prepodes spp., Gynaecia dirce, Historis odious,
Correbidia terminalis, and Sylepta salicalis (22).
The cotton or melon aphid (Aphis gossypii) is also
commonly observed on leaves of yagrumo hembra.
The above species often cause heavy damage to the leaves of mature
trees. Strangulation by vines, including those of the families
Leguminosae, Convolvulaceae, and Malpighiaceae (27), as well as
many species of Philodendron, is also a major cause of
mortality, particularly during the sapling stage. Mortality of
mature trees may be caused by storm damage to the easily broken
branches, by advancing age, or by environmental changes, such as
shading and root competition, caused by the reestablishment of
the climax forest.
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Flowering and Fruiting
provided by Silvics of North America
Yagrumo hembra is dioecious, with
staminate flowers borne in slender, stalked aments 5 to 6 cm (2.0
to 2.4 in) in length, arranged in clusters of as many as 15, and
pistillate flowers in thicker, stalkless aments grouped in
clusters of only 2 to 5. Both staminate and pistillate trees may
be observed in flower and fruit all year long; however, a peak
flowering and fruiting period occurs in Puerto Rico during the
months of January to March, the drier season. This is also the
period of minimum temperatures and minimum day-length (8,26). A
winter flowering and fruiting peak for yagrumo hembra has also
been noted in San Pedro de Montes de Oca (1200 m or 3,937 ft) in
Costa Rica (9).
The slightly fleshy multiple fruit is at maturity gray-green in
color and may be 10 cm (4 in) in length and 15 mm (0.6 in) in
diameter. It is composed of numerous individual fruits,
pentangular or hexangular in shape, each of which contains one
brown seed of about 2 mm (0.08 in) in length. There are 2,500
seeds per gram (70,875/oz), air dried. The extraction factor for
seeds is about 20 percent, because of the gummy material
surrounding each seed (16). Maturation, from emergence of the
inflorescence from the terminal bud to full ripening, requires
from 3.5 to 4 months. Staminate inflorescences remain on the tree
for only 1.5 months and produce copious amounts of wind-borne
pollen approximately 1 to 1.5 months following emergence from the
terminal bud (26).
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Genetics
provided by Silvics of North America
Vegetative morphology of yagrumo hembra throughout the islands of
the Caribbean differs from that of mainland (Central and South
America) representatives of the same species. On the mainland,
yagrumo hembra maintains a symbiotic relationship with Azteca
ants. The species Azteca constrictor and A.
alfaroi have been reported from Venezuela (27). There the
tree also has adaptations, such as a trichilium or highly
modified petiole bases that produce mullerian bodies or food
bodies rich in glycogen. The stinging, aggressive ants live in
the hollow internodes and feed upon glycogen produced by the
tree. Neither the adaptations nor the ants are present on trees
in Puerto Rico. In the Caribbean islands from Trinidad to Puerto
Rico there is a progressive loss of these ant-related traits
(25). Mainland individuals maintain trichilia in the greenhouse;
these appear to be genetic traits and do not depend on ant
stimulation for development (14,25).
Approximately 80 species of the genus Cecropia have been
described; however, only one species is found on the islands of
the Caribbean. A chromosome number of 2n=28 has been reported
(27). Velazquez (27) consolidated three Venezuelan Cecropia
species into a variety of C. peltata: Cecropia peltata
L. var. candida.
Recently, Howard (14) describes Puerto Rican species as Cecropia
schreberiana rather than C. peltata, stating that the
latter is restricted to mainland Central and South America and
Jamaica. C. schreberiana is mentioned as
occurring throughout the remainder of the Greater and Lesser
Antilles. Some place it in its own family, cecropiaceae, with the
genus Cecropia as the type genus.
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Growth and Yield
provided by Silvics of North America
The sapling life stage begins when
lobing of new leaves increases. Diameter growth of nonsuppressed
saplings is significantly faster than that of seedlings. At an
elevation of 400 m (1,312 ft) in the eastern mountains of Puerto
Rico, saplings grow a maximum of 3.0 cm (1.2 in) and a mean of
6.5 mm. (0.26 in) in diameter per year. Mean growth in d.b.h., as
opposed to maximum d.b.h. growth, is low due to the presence of
numerous suppressed saplings in the dense stands which often
occur following disturbance. These saplings grow as much as 2.16
m (7.1 ft) in height per year (26).
A method has been developed for determining the age of yagrumo
hembra based on past height growth (6). The tree has conspicuous
rings and large triangular leaf scars at each node. Turrialba,
where the study was conducted, has a distinct dry season, and
internodes are arranged in short and long series. Short
internodes represent growth during the drier season and long
internodes growth during the wetter season. Annual height growth
was found to be faster in wetter (5.9 m or 19.3 ft and 7.6 m or
24.9 ft) than in drier (1.9 in or 6.2 ft and 2.4 m or 7.9 ft)
regions. It should be stressed that this method is only reliable
for trees less than 5 years in age as height growth slows
significantly later in life (6). Another method for aging yagrumo
hembra is based on regressions of height and diameter on age.
Since this method was developed for young trees and uses mean
d.b.h. and mean height of a stand, it may more accurately
estimate stand than individual age (26).
-Estimation of age of yagrumo hembra from diameter adn height.
A = regression of age of disturbed area on mean height (solid
dot). Y = 0.91 + 1.3X, r² = 0.8. B = regression of
age of disturbed area on mean d.b.h. (open dot). Y = 0.90 +
0.86X, r² = 0.9 (26).
Periodic diameter growth of 4.6 to 5.1 mm. (0.18 and 0.20 in) was
measured for yagrumo hembra (5). Growth rates were among the
slowest measured in the Luquillo Mountains. A mean annual growth
rate in d.b.h. of 2.0 mm (0.08 in) has been reported for mature
yagrumo hembra trees (23) and an annual diameter growth rate of
6.4 mm (0.25 in) was measured in mature dominant trees (26). Once
yagrumo hembra trees reach maturity, diameter growth appears to
decrease. Growth is greatly improved by a dominant crown
position, but little difference is found among codominant,
intermediate, and suppressed trees. Trees in plantations reach a
diameter of 25.0 cm (9.8 in) and a height of 14.0 m (45.9 ft) in
21 years (25). Height growth in yagrumo hembra predominates over
diameter growth (23). This pattern fits well the ecological role
of yagrumo hembra as a gap species.
In the Luquillo Mountains, the density of yagrumo hembra in the
tabonuco forest association (Subtropical Wet) is 83 trees per
hectare (34/acre), and at a higher elevation in the Colorado
forest association (Lower Montane Wet) it is 17 trees/ha (7
trees/acre) (28). Yagrumo hembra had a mean basal area of 18.3 to
22.9 m² /ha (79.7 to 99.7 ft²/acre) in the tabonuco
forest (16). In a 2-ha (4.9-acre) sample of tabonuco forest,
approximately 25 percent of the trees were 10 to 15 cm (3.9 to
5.9 in) in d.b.h, 26 percent were 15 to 20 cm (5.9 to 7.9 in), 20
percent were 20 to 25 cm (7.9 to 9.8 in), and 13 percent were 25
to 30 cm (9.8 to 11.8 in). Only 6 percent had diameters of
greater than 50 cm (19.7 in).
Trees reach canopy height at about 10 years of age and thereafter
survive in the canopy for approximately 20 years. Mean further
life expectancy, 10.25 years, is greatest as the tree approaches
the canopy. High mortality occurs between the production of seed
and the establishment of seedlings (fig. 2).
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Reaction to Competition
provided by Silvics of North America
Yagrumo hembra is most accurately
classed as intolerant of shade. This is especially true during
the seedling and sapling stages. Competition for light and space
during these stages may be the principal factor influencing
growth and survival.
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Rooting Habit
provided by Silvics of North America
The root system of yagrumo hembra tends to
be superficial, and therefore the tree is easily uprooted,
particularly when immature. Prop or stilt roots are a prominent
feature and are often as much as 1.0 m (3.3 ft) in height.
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Seed Production and Dissemination
provided by Silvics of North America
Although as many as
15,000 flowers may be produced per inflorescence, the number of
seeds that mature fully may be as low as 18 percent, or 2,725
viable seeds per inflorescence. Seed production by a mature tree
during one reproductive year has been estimated to be as high as
I million (13,26). Seed production is size or age specific,
however, and increases throughout the lifetime of the tree. In an
estimated life span of 30 years, as many as 6 to 7 million seeds
may be produced by a single tree. Reproductive maturity is
reached at an earlier age, 3 or 4 years by pistillate than by
staminate trees, which mature at 4 to 5 years. Reproductive age
may depend upon need for allocation of resources to rapid initial
height growth and therefore the height and proximity to
surrounding vegetation. Roadside trees, in a more open
environment, reached reproductive maturity sooner (3 to 4 years)
than forest gap trees (5 to 6 years) (26). Seed production
probably decreases as a tree approaches the senescent state. In
this stage there appears to be an increase in branch loss.
Seeds are dispersed primarily by bats and birds (3,7,11,18,24);
seeds pass through the digestive tracts unharmed (24). In Puerto
Rico, 15 species of birds and bats have been reported to feed on
mature yagrumo hembra fruit. Some of the more common species
include the Jamaican fruit eating bat, the banana quit, the
pearly-eyed thrasher, the red-legged thrush, and the reina mora
(18,26).
These species frequent both open and forested areas, so that seeds
are dispersed widely and are available in forest soil in the
event of a disturbance (12). As many as 398 seeds per square
meter (37/ft²) have been reported to be present in
undisturbed lower montane rain forest soil (2,26). Blum (3)
reported that yagrumo hembra seedlings grew in 4 to 10 soil
samples taken from mature forests in Panama. Other secondary
species such as yagrumo macho, cachimbo comun (Psychotria
berteriana), and guano were also present in these soils.
Seeds may also be dispersed when the entire fruit cluster falls to
the ground upon ripening, but these seeds show a reduced
viability as the embryos are damaged by fungi and insects of the
family Nitidulidae. Laboratory- stored seeds retained viability
for a minimum of 6 months, whereas seeds stored on the forest
floor retained viability for only 2 to 3 months. This reduced
viability under natural conditions indicates that a constant
addition of seeds to the seed bank of the forest floor is
necessary for rapid and successful colonization of a forest gap.
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Seedling Development
provided by Silvics of North America
Seeds require full sunlight for
successful germination. Thus, seeds present on the floor of
closed forests germinate only when some type of canopy gap
occurs. Given full light conditions, germination may be as high
as 80 to 90 percent (3,16,26). Germination is epigeal and in an
open field was shown to be reduced by the presence of a layer of
leaf litter. Other factors that may interact with increased light
intensity in promoting germination include higher surface soil
temperatures, fluctuations in air temperature, and changes in
soil moisture. With the decreased light intensity beneath the
closed forest canopy, spectral composition (an increased
proportion of infrared light) may also become critical to
germination (26). A decreased ratio of infrared to red light has
been shown to inhibit germination of successional species. In
open fields there was less yagrumo hembra seed germination than
was observed in light gaps. This may result from the extremely
high and fluctuating surface soil temperatures or to fluctuating
but frequently low soil moisture, or both (table 1).
Table 1- Microclimatic- and physical factors of
selected environments
Item
Environment¹
Open field
Forest
Gap²
Temperature, °C
Mean
25.4
22.7
23.2
Daily variation
8.4
2.4
3.0
Soil surface
30.2
22.3
24.8
Temperature, °F
Mean
77.7
72.9
73.8
Daily variation
47.1
36.3
37.4
Soil surface
86.4
72.1
76.6
Relative humidity, %
Mean
77
94
85
Daily variation
34.0
4.5
10.3
Soil moisture, % dry wt.
47.8
78.3
47.6
¹Values are means for all months, August 1977 to January 1878
(25).
In the nursery, seed is germinated under light shade on a seedbed
prepared from equal parts of clay, sand, and filter press cake.
Light shade is maintained until seedlings shade the germination
media (16).
Seedling leaves are distinct from those of the mature plant. They
are downy on both surfaces, lanceolate, unlobed, and finely
toothed. In the early sapling stage, 0.5 m (1.6 ft) tall, leaves
begin to show signs of lobing. Ultimately, new leaves have 7 to
11 palmate lobes and resemble those of the mature plant, dark
green and scabrous above and covered with a dense surface of
white hairs below. Seedlings grow rapidly in height, reaching
10.0 to 15.0 cm (3.9 to 5.9 in) in 10 weeks (16) and as much as
2.1 m (6.9 ft) in the first year (21). The ratio of
photosynthesis to respiration of yagrumo hembra seedlings has
been reported to be much greater than 1 (20).
Under natural conditions, seedling mortality may be extremely
high. In a forest opening, 99 percent of germinating seedlings
may die within the first year. This is the life stage during
which the greatest mortality occurs. During nursery trials,
volunteer seedlings suffered 45 percent mortality during the
first 9 months (10). However, seedlings transferred when 25.0 to
60.0 cm (9.8 to 23.6 in) in height to the field following a
2-week shaded period and gradual diminishing of shade showed a
survival of as high as 80 percent. In 7 months they had reached
2.0 m (6.6 ft) in height (16).
-Survivorship curve for yagrumo hembra. A is based on
disturbed areas; B is based on life cycle stages (26).
Growth in height is most rapid during the first 4 to 5 years, but
the tree grows relatively little in diameter during the same
period (6). In the Luquillo Mountains of eastern Puerto Rico,
maximum seedling height growth under natural conditions was 1.14
in (3.7 ft) and the mean 0.73 m (2.4 ft) per year. Maximum
diameter growth measured immediately above the root collar was 5
mm (0.20 in) and the mean growth was 3.6 mm (0. 14 in) during an
8 month period (26).
Seedlings which are overtopped and thus shaded for extended
periods of time do not survive for long. Potted seedlings
transferred from a forest gap to closed forest died within
several months and showed little if any growth. Potted seedlings
remaining in the gap exhibited 100 percent survival as well as
diameter and height increases. A disturbed area that is invaded
rapidly by grasses, ferns, or vines shows a decreased density of
yagrumo hembra during the seedling and sapling stages (26).
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Soils and Topography
provided by Silvics of North America
Yagrumo hembra grows on the Ultisols of the central and eastern
mountains of Puerto Rico, the Mollisols and Alfisols of the
limestone hills of the northwest, the Oxisols of the western
mountains underlain by serpentine, and also the Mollisols and
Inceptisols of the northern coastal plain. It is found from 50 to
1300 in (164 to 4,265 ft) in elevation on ridges, slopes, and
flats but appears to be at its optimum in coves or protected
areas. It is often found on steep slopes where landslides or tree
falls have occurred, and in these areas its prop or stilt roots
may be conspicuous. Yagrumo hembra grows on alluvial, colluvial,
and residual soils neutral to acidic in nature. These soils may
be derived from tuffs; volcanic rock, andesitic or dioritic in
composition; limestone; or serpentine. Soil texture may range
from heavy clay to sandy, but a clay-loam soil is optimal.
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Special Uses
provided by Silvics of North America
As a dominant secondary species, yagrumo hembra is invaluable in
regeneration of the forest following disturbance. As it rapidly
forms a dense stand, nutrients may be conserved and the
environment beneath ameliorated sufficiently to allow species
characteristic of a later stage of succession to germinate and
grow. In this manner the soil may be stabilized following a
disturbance such as a landslide. Its broad canopy protects the
soil from excessive erosion and reestablishes shade conditions to
the forest floor.
With a specific gravity of 0.29, the wood of yagrumo hembra is
only slightly heavier than local balsa. The wood is used in the
finish of "puertorrican cuatros," a local guitarlike
musical instrument. Principal uses for wood in Puerto Rico once
included excelsior. The wood also was shredded and mixed with
cement to form a building or insulation board (4). Elsewhere,
yagrumo hembra is used to produce paper pulp. Fiber yield per
cord of fresh material is low, but it cooks rapidly, giving
unbleached pulps that approach the best northern deciduous
neutral sulfite pulps, e.g., aspen, in quality. A yield of 56 kg
(123.5 lb) of pulp per 100 kg (220.5 lb) of wood has been
estimated (17). The wood may be substituted for use in products
made from heavier grades of balsa. It is also used for boxes,
crates, and matchsticks (19). The hollow branches are often split
and used for gutters or troughs, and entire branches are used for
pipe floats, life preservers, and tamborines.
Various substances have been extracted from yagrumo hembra for
medicinal use (19), including one that increases cardiac muscular
contraction and acts upon the kidneys as a diuretic. A substance
extracted from the roots is said to heal wounds, and the leaves
are often used as a poultice to reduce swelling and as an
abrasive (27).
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Vegetative Reproduction
provided by Silvics of North America
Yagrumo hembra sprouts easily.
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Distribution
provided by Silvics of North America
Yagrumo hembra is also native throughout the Greater and Lesser
Antilles and in Central America from Yucatan, Mexico, to Costa
Rica. In South America it has been reported from Venezuela,
Colombia, Brazil, and the Guianas (19).
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Brief Summary
provided by Silvics of North America
Moraceae -- Mulberry family
Susan R. Silander and Ariel E. Lugo
Yagrumo hembra (Cecropia peltata), also called
trumpet-tree, is a rapidly growing neotropical tree, an important
secondary species that is common in Puerto Rico. It is an early
invader of forested areas subject to natural or human
disturbances and is conspicuous due to its spreading crown and
large peltate leaves 30 to 50 cm (12 to 20 in) in diameter, with
silver-white lower surfaces.
- license
- cc-by-nc
- copyright
- USDA, Forest Service
Cecropia peltata
provided by wikipedia EN
Cecropia peltata is a fast-growing tree in the genus Cecropia. Common names include trumpet tree, trumpet-bush, bacano and snakewood.[1] It is listed as one of the world's 100 worst invasive alien species.
Description
Cecropia peltata is a fast-growing tree,[2] normally reaching 15 metres (49 ft), but occasionally growing up to 25 metres (82 ft) tall. The leaves are large – 10–60 centimetres (4–24 in) in length and width, but more commonly about 20 × 20 centimetres (8 in) and palmately divided into 7–11 (but generally 8–10) lobed. The upper surfaces of the leaves are scaled, while the lower surfaces are covered with minute hair, interspersed with longer ones. The petioles are generally 20–50 centimetres (8–20 in) long, while the branches are green and covered with short, stiff hairs.[3]
Like other members of the genus, C. peltata is dioecious – there are separate male and female plants. Male flowers, which are 1–1.5 millimetres (0.039–0.059 in) long, are borne in spikes 10–60 centimetres (4–24 in) long. The male inflorescence is enclosed in a spathe which splits open and drops off once the anthers mature. The female flowers are borne in paired spikes 3–5 centimetres (1.2–2.0 in) long. The fruit, which is about 2 millimetres (0.079 in) long, is an achene which is enclosed in a fleshy jacket which forms from the perianth.[3]
Taxonomy
The species was described by Carl Linnaeus in the 1759 edition of Systema Naturae. It was the first species to be described in the genus and was originally applied to many species of Cecropia. As additional species were described, the usage narrowed. The genus was placed in the family Urticaceae by Adolf Engler in 1889. E. J. H. Corner suggested moving the genus to the Urticaceae in 1962, while Cornelis Berg placed Cecropia in its own family, the Cecropiaceae.[3] Based on molecular data, the Angiosperm Phylogeny Group merged the family back into the Urticaceae.[4]
Distribution
Cecropia peltata ranges from southern Mexico through Central America to northern South America, Guyana, Trinidad and Tobago, and Jamaica, and has been introduced in Africa, Asia and the Pacific.[3] The species has been listed as one of the hundred worst invasive alien species by the Invasive Species Specialist Group.[5] Replacement of its very close ecological analogue, the native African Musanga cecropioides, by C. peltata has been reported along major roads of Cameroon.[6]
References
- license
- cc-by-sa-3.0
- copyright
- Wikipedia authors and editors
Cecropia peltata: Brief Summary
provided by wikipedia EN
Cecropia peltata is a fast-growing tree in the genus Cecropia. Common names include trumpet tree, trumpet-bush, bacano and snakewood. It is listed as one of the world's 100 worst invasive alien species.
- license
- cc-by-sa-3.0
- copyright
- Wikipedia authors and editors