Their beauty adds seasonal.
character to the landscape and a serene refuge from the demands of .
daily living.
Australia suffers greatly from salinity and rapidly rising water tables. .
The primary cause of dry land salinity is the clearing of native bush.
Unless re-vegetation occurs, much land will eventually become .
useless for farming. .
In the process, it won't only be the farmers who suffer. Hundreds of .
rural communities and our economy will be badly affected as well. .
Salinity is one of the biggest problems we face in Australia. .
Needing to grow food for a growing population, white settlers cleared .
billions of trees and much of the supporting vegetation. Little did they .
know that their actions would cause water tables started to rise, .
bringing salt to the surface. The consequences have been enormous. .
Salinity costs us around $270 million a year in lost agricultural .
production, damage to property and environmental destruction. And .
it's growing.
So, Why Trees.
During evolution, the individual plants and animals with the best .
"fit" in an ecosystem thrive, because they are the ones whose.
offspring are most likely to survive to maturity and pass their genes .
on to future generations. .
In the plant world, being "fit" doesn't mean being strong. It means .
being able to a) compete for resources (like light, space, and .
nutrients); b) avoid predation (by both mammals, such as deer and .
porcupines, and by insects); and c) resist the impacts of disease and .
severe weather. .
Being taller gives a plant an obvious advantage in the competition for.
light. But that advantage comes at a cost. Very tall plants (like trees) .
need to be strong enough to withstand the tremendous forces from.
both summer winds and winter snow and ice, forces from which .
shorter plants are protected. The buds of our taller trees and shrubs,.
for instance, are exposed to the sometimes Arctic temperatures of our .
winters, while smaller plants that pass the winter as bulbs or seeds.
