Drought, especially prolonged or severe drought, can be a
major stress in forest ecosystems.
Drought can kill trees directly or indirectly through insect attack or
wildfire. Both of which are more likely to occur during drought.
major stress in forest ecosystems.
Drought can kill trees directly or indirectly through insect attack or
wildfire. Both of which are more likely to occur during drought.
Tree mortality impacts most of the ecosystem services
provided by forests, including the amount of wood that grows, how much carbon
is captured and stored, the health of critical wildlife habitat, water yield
and quality, and even whether it’s safe to pursue recreational activities such
as hiking or hunting.
provided by forests, including the amount of wood that grows, how much carbon
is captured and stored, the health of critical wildlife habitat, water yield
and quality, and even whether it’s safe to pursue recreational activities such
as hiking or hunting.
Fortunately, there are forest management practices that can
help land owners and managers continue to supply the goods and services society
needs, even when forests are affected by drought. These practices focus on
actions that reduce stand density (the number of trees on an acre) and adjust
species composition (the species of trees and other vegetation growing on a
site). Fewer trees might not necessarily use less water than more trees, but
they might be healthier and better able to resist drought stress and insect
attack.
help land owners and managers continue to supply the goods and services society
needs, even when forests are affected by drought. These practices focus on
actions that reduce stand density (the number of trees on an acre) and adjust
species composition (the species of trees and other vegetation growing on a
site). Fewer trees might not necessarily use less water than more trees, but
they might be healthier and better able to resist drought stress and insect
attack.
Some tree species are inherently more resistant to drought
and fire than others. So, by managing forest density and composition, land
owners and managers help ensure that resources are available to support the
growth of desired forest vegetation.
and fire than others. So, by managing forest density and composition, land
owners and managers help ensure that resources are available to support the
growth of desired forest vegetation.
Thinning can be used to reduce stand density and adjust
species composition, with the goal of reducing or mitigating drought-related
stress and can improve stand resistance and resilience.
species composition, with the goal of reducing or mitigating drought-related
stress and can improve stand resistance and resilience.
In newly planted stands, seedlings with limited root
development are vulnerable to extreme drying, because their roots are too small
or poorly developed to find scarce soil moisture. When drought is expected
during or following planting, land owners and managers should consider using
seedlings with larger root systems or appropriate “containerized” seedlings
that have a plug of soil already attached to the roots.
development are vulnerable to extreme drying, because their roots are too small
or poorly developed to find scarce soil moisture. When drought is expected
during or following planting, land owners and managers should consider using
seedlings with larger root systems or appropriate “containerized” seedlings
that have a plug of soil already attached to the roots.
Managing understory vegetation or controlling competition
from other plant species during drought is important in established stands as
well as for regeneration. For example,
an open understory of grasses and legumes may better tolerate drought than a
thick midstory of shrubs and small trees.
from other plant species during drought is important in established stands as
well as for regeneration. For example,
an open understory of grasses and legumes may better tolerate drought than a
thick midstory of shrubs and small trees.
Source:USDA
