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HaciendaRustica.Com only uses cut by conservation programs regulated by the U.S. Department of Forestry U.S. kiln dried pine .06 h. f. from Washington and Oregon since 1980
Pine
V.3
Alternative Management Systems of
Termites in
Forestry
Current chemical control A number of chemical control methods are currently used to protect trees against attack by termites. These methods have remained largely the same over the years, although the chemicals used have changed to reduce the environmental impact of these treatments. Many, or all, of the organochlorines, which are persistent organic pollutants, are no longer registered for use in most countries. Current chemical control methods employed are soil treatment, treatment of seedlings before transplanting and baiting techniques. Soil
treatment
Soil treatment to protect trees from
attack by termites
involves the application of chemicals to the soil surrounding the base
of the tree. This may be done at the time of transplanting seedlings
from the nurseries into the field, or it can be done to trees already
in-ground. In the former, granular formulations of insecticides (e.g.
fipronil) are usually used, since they are easy to carry into the field,
and they are applied into the planting hole. In the latter, the soil at
the base of the tree is removed to form a cavity or trench around the
tree, and liquid-based chemicals are poured in and allowed to seep into
the ground by gravity and capillary action. The cavity or trench is
then filled over with the soil originally excavated from around the
tree, and treated as well. Chemicals currently used include
chlorpyrifos, imidacloprid and fipronil.
Treatment of seedlings before transplanting
Treating seedlings before
transplanting reduces the labor involved in field-based treatments, but
provides less protection to the seedlings. The seedlings are usually
prepared with granular insecticide mixed into the soil at the time of
planting in the nursery.
Baiting techniques
Aggregation and baiting techniques,
using the POP chemical mirex as the active ingredient, are used
primarily in Australia as a management measure
for Mastotermes darwiniensis (see Australia,
Termites in
Agroecosystems).
Alternative control: traditional methods Many traditional methods of control of termites in forest plantations have a sound basis in the principles of ecology. They are often simple and cost effective means of minimizing termite problems through silvicultural practices that involve thoughtful planning before establishing a plantation and suitable practices following establishment. These, some of which are inter-related, are listed below:
Selecting low risk sites Termite pest species have their own native habitats in which they are most abundant. For example, in Southeast Asia, the tree-killing termite species, Coptotermes curvignathus, is abundant in peat swamps. The abundance of termite species in particular plantation sites is often, therefore, reflective of the history of the site. Plantations established in areas once occupied by peat swamps in Southeast Asia often have a relatively high incidence of attack by Coptotermes curvignathus. One way of avoiding the problem of termites in forest plantations is not to plant susceptible species of trees on sites known to be high-risk. Use
of species suitable for a region Tree species-site matching is an important aspect of termite management. Trees grown in regions to which they are not suited may be more stressed and, hence, more prone to attack by termites. Acacia mangium for example, which is widely planted in parts of Southeast Asia, does better in a climate with a marked season, such as a wet and dry season. In other areas, it tends to develop a bushy growth form, which requires more pruning and predisposes the trees to attack as a result of mechanical injury to the trees. Terrain, climate and soil properties (physical and chemical) should be suitable for the tree species chosen, bearing in mind its native habitat and its degree of tolerance outside the conditions in which it naturally grows. http://www.chem.unep.ch/pops/termites/termite_ch5.htm
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