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<br />By PETER FRIED.ERICI
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<br />Tou.gh, prolific, and exclusionarv, the
<br />tamarisk is "planta non grata" in the
<br />Southwest, but-it's a2)>>arentlv here to sta~
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<br />PJi.ml._ f~~1]g!!-!9:":"_ - - - - - - -
<br />a freelance writer specializing
<br />in nature and conservation
<br />topics, writes a quarterly
<br />nature-education leaflet Jor
<br />the Roger Tory Peterson
<br />Institute oj Natllral History.
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<br />t's probably just as well .that the name of the
<br />. first person to plant a saltcedar in the
<br />Southwest is lost to history. He, or she, was
<br />. no doubt praised some 200 years ago for the
<br />inspiration that brought a source of shade and
<br />. wood to the sun-bciked desert. But today's
<br />reaction would be quite.different .
<br />..
<br />In two centuries tlie alien saltcedar Ius established itself along
<br />numerous rivers and reservoirs, where biologists and land managers
<br />regard it as a noxious plant pest. It stands accused of degrading
<br />wildlife habitat, ruining the recreational amenities of riparian areas,
<br />wasting scarce water, and even increasing the severity of Roods. Its
<br />impact has been especially great on riparian woodlands, which sup-
<br />port the greatest quantity and diversity of life-both animal and
<br />human-in the desert landscape, and which are among the most
<br />imperiled ecosystems in North America.
<br />Saltcedar's negative effects are a direct reRection of exactly
<br />those qualities early settlers in the Southwest found so positive. Its
<br />roots stabilize streambanks against the Rooding typical of desert
<br />washes and rivers. Its foliage provides precious shade for poultry
<br />and,livestock. It can be cut for firewood. Its abundant sprays of
<br />white or pink flowers provide some ornamentation in an area
<br />where the vegetation often seemed alien, if not outright hostile, to
<br />new inunigrants.
<br />And it is remarkably hardy. "It'll grow anywhere it can get its
<br />feet in water," says Mary Irish, director of horticulture at the Desert
<br />Botanical Garden in Phoenix. "Its eXtremely tolerant of any soil,
<br />including salty soil, and it doesn't mind the heat at
<br />all."
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<br />The tamarisk family is native to southern
<br />Eurasia, and over time, several species were intro-
<br />duced here. One-the evergreen athel tamarisk or
<br />Tamarix apllyllo----grows at least 50 feet high and is
<br />a'valued shade tree. Beekeepers say its Rowers pro-
<br />duce excellent honey. The other species, which
<br />are deciduous, are referred to as Tmnarix chintllsis,
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<br />T. ram~4sima, and T. parvijlora. Because they appear to hybridize.
<br />and are virtually impossible to tell apart, some botanists consider
<br />them all to be ~embers of the same species.
<br />This is the shnib or tree called saltceclar, a name whose latter
<br />half refers to tiny. scaly leaves that resemble cedar scales.. And it is
<br />sattcedar because the plant exudes. salt from glands on its leaves.
<br />Grab a branch, and you end up with a residue thick enough to
<br />taste. When the leaves drop in the autumn, they pass that salt to the
<br />soil, which may eventually become too saline to support most
<br />native plant species.
<br />Given ample water and space, a saltceclar can become a medi-
<br />um-sized tree--the largest known in the U.S. is a -l-l-foocer in New
<br />Mexico. In the wild, though, it more conullonly forms dense thick-
<br />ets of many-branched shrubs, all growing to a height of J 5 or 20
<br />feet. The foliage is so dense that almost nothing can grow unde:r it.
<br />Saltcedar is not really adapted to aridity. It grows only where
<br />water runs near the surface, and it is spendthrift-a large spc:cimen
<br />uses perhaps 200 gallons a day. It has been estim:lte:d that all the
<br />saltcedar in the Southwest uses, per year, twice as much waCe:r as all
<br />the cities of southern California.
<br />Dense stands of saltcewr trap sediment durin~ floods, narrow-
<br />ing water channels and perhaps increasing the SI:\'e:rity oi subse-
<br />quent Roods. Along the C610r.Jdo River, saltce:d;lf thickets have
<br />overgrown many beaches long favored for campin~ ;md recreation.
<br />Wildlife is far less abundant in saltcei:i.1r thickets than in sup-
<br />planted native woodlands, largely because native plant~ act as host to
<br />many more insect species. A smdy along the: lower Color.Jdo River
<br />showed that during the winter an undisturbed native woodland of
<br />cottonwood and willow supporce:d an average of
<br />154 birds per 100 acres. Only four birds lived in an
<br />equivalent area of saltcedar. Fe:\\' birds nesc in
<br />saltcedar, perhaps because che feathery leaves do
<br />not provide the same prote:ction from ince:nse
<br />summer heat as do che broad leaves of (o([on-
<br />woods and willows.
<br />It is extremdy difficult to descroy an estab-
<br />lished thicket. .. Afte:r any environmencal cJlarnity
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<br />AMERIC^N FORESTS J^NlJ^R y/FEIlRU^RY 1995... 45
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