Bosque
Bosque is the name for areas of
riparian forest found along the
flood plains of stream and river banks in the
southwestern United States. It derives its name from the
Spanish word for
woodlands.
In the predominantly arid or semi-arid southwestern United States, the bosque is an
oasis like ribbon of green vegetation, often canopied, that exists near rivers, streams, or other water courses. The most notable bosque is a 200 mile-long ecosystem along the middle
Rio Grande in
New Mexico that extends from
Santa Fe past
Socorro.
Encyclopedia
Bosque is the name for areas of
riparian forest found along the
flood plains of stream and river banks in the
southwestern United States. It derives its name from the
Spanish word for
woodlands.In the predominantly arid or semi-arid southwestern United States, the bosque is an
oasis like ribbon of green vegetation, often canopied, that exists near rivers, streams, or other water courses. The most notable bosque is a 200 mile-long ecosystem along the middle
Rio Grande in
New Mexico that extends from
Santa Fe past
Socorro.
The trees in the bosque habitat are generally smaller species such as
mesquite which rarely exceed 10 meters. Larger
cottonwood trees are also common in some areas. Because there is only a single canopy layer and because the tree species found in the bosque are generally
deciduous, a wide variety of shrubs, grasses, and other understory vegetation is also supported. Desert hackberry, blue palo verde, graythorn, Mexican elder, virgin's bower, and Indian root all flourish in the bosque. The habitat also supports a large variety of
lichens. For a semi-arid region, there is incredible
biodiversity at the interface of the bosque and
desert ecosystems.
The endangered bosque
Currently the bosque is being threatened by increasing human encroachment and the introduction of several harmful
invasive species, most notably the Russian olive tree and
salt cedar tree species, which grows in dense thickets and drops much flammable debris throughout its lifespan. On average, invasive trees consume up to twice as much water as native cottonwoods, adding to the water problems in this already dry region.
Unlike many forest habitats in the western United States which rely on occasional
wildfires to clear debris and promote seed germination, bosque plants were adapted for seasonal flooding to accomplish these tasks. However, the construction of
dams,
levees, and the increasing amount of water siphoned off for residential and agricultural use have lead to a marked drop in the number of floods along bosque sustaining water courses.
The bosque is also threatened by man made fires. For instance, two fires broke out in late June, 2003 along the stretch of the
Rio Grande flowing through
Albuquerque. For a few intense days, frightened citizens agonized as hundreds of acres of bosque went up in smoke literally in the middle of the city. Larger fires which burned many thousands of acres have taken place further south in Valencia and Socorro Counties.
Fires are particularly damaging since several of the invasive species are more fire resistant than native species. Furthermore, the invasive salt cedars help the spread of fires. When a fire comes, it spreads along the brush, climbs up the salt cedars, and leaps into the crowns of the cottonwoods, where breezes carry burning embers to neighboring sections. The salt cedar will quickly regrow in a burnt area, choking out native species and forever altering the bosque.
Hope for the future
Fires and encroachment notwithstanding, recent events have given scientists and local residents alike hope for positive change in the bosque's future. By garnering national attention, funding has been obtained to clear exotic species from large sections of the bosque. Where possible, levees and other flood control devices along the Rio Grande are being removed to allow the river to undergo its natural cycle.
Most importantly, heavy precipitation in the spring and summer of 2005 doubled the flow in the river, scouring invasive species off sandbars, stirring up sediments, and overflowing the banks in many places. Much of the Southwest had experienced upwards of 4 inches of rain above average by June. Scientists hope this may be an early sign of the end of the
drought that has long plagued the region. In the bosque, this trend means moist, nutrient rich soil that the cottonwood seedlings need to take root and more habitat for the endangered silvery minnow and Southwestern willow flycatcher.
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