BOTANICAL AND ECOLOGICAL CHARACTERISTICS
SPECIES: Casuarina spp. | Australian Pine 



GENERAL BOTANICAL CHARACTERISTICS : 
Australian pine is a medium to tall evergreen tree.  It has a stout
trunk with rough bark and erect or semispreading main branches and
drooping twigs [12].  Its leaves are jointed and scalelike.  Its fruits
are round and warty with winged seeds.  Trees can be dioecious or
monoecious; male flowers are borne at the tips of twigs, while female
flowers form on nonshedding branches [3,14].  Australian pine fixes
nitrogen with the aid of Frankia spp. fungi.

Characteristics of individual species are as follows:

C. cunninghamiana - 80 feet (25 m) in height, 2 feet (6 m) d.b.h.,
                    dioecious, nonsprouter.
C. equisetifolia - 50 to 100 feet (15-30 m) in height, 1.0 to 1.5 feet
                   (3-5 m) d.b.h., monoecious, nonsprouter.
C. glauca - 40 to 50 feet (10-15 m) in height, 1.5 feet (5 m) d.b.h.,
            dioecious, agressive sprouter, in Florida, usually does not
            produce fruit [12].  


RAUNKIAER LIFE FORM : 
   Phanerophyte


REGENERATION PROCESSES : 
Australian pine regenerates by seed as well as vegetatively through
sprouting [3,12,14].  It is fast growing (5 to 10 feet [1.5-3 m] per
year) [14].  Seeds average 300,000 per pound.  No pregermination
treatment is necessary.  Seeds can remain fertile for a few months to a
year and will germinate in moist and porous soil, sometimes within 4 to
8 days of dispersal [14].


SITE CHARACTERISTICS : 
Because of its nitrogen-fixing capability, Australian pine can colonize
nutrient-poor soils [12].  It can grow in sloughs, sawgrass (Cladium
jamaicensis) glades, wet prairies, saltmarshes, pinelands, along rocky
coasts, on sandbars, dunes, and islands, and in water-logged clay or
brackish tidal areas [3,10,14,17,18].  C. equisetifolia is found only in
south Florida because of its cold intolerance.  It is resistant to salt
spray but not to prolonged flooding.  C. cunninghaminana grows along
freshwater streambanks and is not salt tolerant [3].  It is more
resistant to cold temperatures than C. equisetifolia [12].  C. glauca
grows on steep slopes as well as in intermittently flooded or poorly
drained sites.  It is salt tolerant [3].

Some associates of Australian pine include eucalyptus (Eucalyptus spp.),
melaleuca (Melaleuca quinquenervia), lovegrass (Eragrostis spp.), muhly
grasses (Huhlenbergia spp.), beard grasses (Andropogon spp.), plume
grass (Erianthus giganteus), saltbush (Baccharis halimifolia), wax
myrtle (Myrica cerifera), willow (Salix spp.), sweetbay (Magnolia
virginiana), redbay (Persia borbonia), and coco plum (Chrysobalanus
icaco) [18].  Native associates in the Northern Mariana Islands include
Neisosperma, Barringtonia, Terminalia, Heritiera, Cynometia, and Cordia
[5,6].


SUCCESSIONAL STATUS : 
Australian pine is listed as a dominant species in some South Pacific
island's vegetation types [2,5,6].  It is a warm weather species, not
native to North America.  It can be a primary or secondary colonizer in
disturbed areas of Florida [3,10].


SEASONAL DEVELOPMENT : 
Australian pine can flower and fruit year-round in warm climates [3].
Its peak flowering time is between April and June, and its peak fruiting
time is between September and December.  The minimum seed-bearing age is
4 to 5 years, and it produces a good seed crop annually.  C.
equisetifolia usually flowers and fruits two times a year:  between
February and April, and September and October.  It produces fruit in
June and December.  The fastest growth occurs in the first 7 years with
maximum growth reached in 20 years.  The maximum lifespan of Australian
pine is 40 to 50 years [3].

Related categories for Species: Casuarina spp. | Australian Pine