is the most important genus in forestry, with
protecting the desert highways,
the coastal housing. Annual plantings were one million seedlings in 1975, four million in 1980, projected at 1015 million in 1990. In South Africa, used for firewood, poles, reclamation, shelterbelts, timer, and windbreaks. Planted as a windbreak, superior to pine, in California. The timber is durable and useful for flooring. The wood is dark, close-grain, and nicely marked. The bark can be used as tanbark. Foliage is liable to be eaten by livestock (Watt and Breyer-Brandwijk, 1962). In Argentina, it is planted on the Pampas as a windbreak and shade tree, along stream banks to protect them from erosion. Because of its importance for protecting stream banks from erosion, it cannot be felled without permit in New South Wales. In Puerto Rico, grown for ornament, shade and windbreak.
Once bioflavonyls were thought restricted to gymnosperms and
but now they have been found in other angiospermous genera, both monocots and dicots, o-coumaric acid has been reported in the genus as well as protocatechuic acid. Asparagine and glutamine accounted for 92% of the total amino acid in the nodules. In root nodules of legumes, infection increases markedly the IAA presents but in
) there is an increase in IAA oxidase and no detectable IAA. Hence the nodule-roots grow upward rather than downward. Hemoglobin levels in the root nodules are said to compare with those in the pea (Postgate, 1971). Bark grown in Natal yields 6.711.3% tannin. The pollen may be allergenic.
Medium sized tree 1520 m or more tall, the trunk straight, to 30 cm in diameter. Closely resembling
but the fruiting cones are much smaller (ca 10 mm long), globular, very regular, with prominent valves. Scale leaves 810, whorled at the nodes, minute. Male flowers crowded in rings equipped with grayish scales, each with one exposed brown stamen, less than 0.5 mm long, with two minute brown scalelike sepals. Seeds pale brown, ca 440,000550,000/kg.
Reported from the Australian Center of Diversity, the river sheoak, or cvs thereof, is reported to tolerate acid soils, alkaline soils, calcareous soils (perhaps chlorotic), drought, muck, sanddunes, salt, weeds, and wind. This species is more cold tolerant than the other Casuarinas grown in Florida (NAS, 1983e). In South Africa, it is said to be hardy to drought and frost. Not as salt tolerant as
Native to eastern and northern Australia, growing from southern New South Wales (latitude 37°S) to northern Queensland (latitude 12°S). It often fringes freshwater streams and rivers on both sides of the Great Dividing Range. A distinct race., possibly a separate species, occurs along larger rivers in higher rainfall areas of the Northern Territory (NRC, 1982). Introduced in Argentina, Arizona, California, Chile, Egypt, Florida, Israel, Mexico, Morocco, South Africa, Zimbabwe.
Ranging from Warm Temperate Dry to Moist through Tropical Thorn to Dry Forest Life Zones, the river sheoak is reported to tolerate annual precipitation of 5 to 15 dm. Has survived temperatures of -8°C with no apparent injury. Said to tolerate up to 50 light frosts per year. Usually occurs in alluvial soils varying from silty loams to sands and gravels.
spp. have been observed as the first higher plant species to populate newly formed coral atolls in the Pacific (Postgate, 1971).
In Hawaii seed are broadcast in spring and covered lightly with less than one cm soil. A seedling density of ca 200325/m
is recommended, but final densities should, of course, be much thinner (Ag. Handbook 450). Molybdenum is necessary for dinitrogen fixation.
In continental U.S., seed bearing age is 45 years and flowering peaks from AprilJune, fruiting from SeptemberDecember. Good seed crops occur annually (Ag. Handbook 450). Timber can be harvested as needed. Litter and firewood is often gathered as the accumulation justifies.
spp. have very dense wood, with specific gravity 0.81.2, calorific value of ca 5,000 kcal/kg, splits easily, and burns slowly with little smoke or ash. It also can be burned when green, an important advantage in fuel short areas. From their fourth year, trees shed ca 4 tons cones/year. These too make good pellet-sized fuel (NAS, 1983e).
spp. are good for charcoal, losing only 2/3 their weight, compared to 3/4 for most woods.
This plant is listed by the U.S. federal government or a state. Common names are from state and federal lists. Click on a place name to get a complete noxious weed list for that location, or click here for a composite list of all
Federal and State Noxious Weeds