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.. \ ~ t J Ii -' " By PETER FRIEDERICI Tough, prolific, and exclusionary, the tamarisk is "planta non grata" in the Southwest, but-- it's a2Parently hereto sta~ t's probably just as well that the name of the first person to plant a saltcedar in the Southwest is lost to history. He, or she, was no doubt praised some 200 year.; ago for the inspiration that brought a source of shade and wood to the sun-baked desert. But today's reaction would be quite- different. . In two centuries the alien saltcedar has established itself along numerous rivers .and reservoirs. where biologists and land managers reg.ud ir as a noxious plan[ pest. It stands accused of degrading wildlife habitat, ruining the recreatiollal amenities of riparian areas, wasting scarce Mter, and even incre;lS1ng the severicy of Roods. Its impact has been especially great on riparian woodbnds, which sup- port the greatest quantity and diversity of life-both animal and human-in the desert landscape, Jnd which are among the most imperiled ecosystems in North America. Saltcedar's negative effects are a direct reflection of exacdy those qualities early settlers in the Southwest found so positive. Ics roOCS stabilize streambanks against the Aooding typical of desert washes and rivers. Its foliage provides precious shade for pouhry and liveswck. It can be cut for firewood. Its abundant sprJYs of white or pink flowers provide some ornamentation in an area where the veget.ation often seemed alien, if nor outright hostile, w new irrunigr.mts. And it is remarhbly h.ardy. "It'll grow anywhere i[ can get Its feet in YJater," says M.ary Irish, direcwr of horticulture ;H the Desen Bounical Garden in Phoenix. "It's extremely tolerant of .any soli, including salty soil, .and it doesn't mind [he heat at all." The tamarisk family is native to southern Eunsia, and over time, sever.ll species were intro- duced here. One--the evergreen athe! tamarisk or Tamarix apilyllQ---j!,rows at least 50 feet high and IS t v:llued shade tree. Beekeepers say its flowers pro' duce excellent honey. The other species, which .are deciduous, are referred to as 7izmarix chintllsis, T. ramo~4sima, .and T parviflora. Bec.ause they appear W hybridize, and .are Virtually impossible w tell apart, some bQ(;lnists consider them all to be membeJ'5 of the same species. This is the shrub or tree called saltcedar, a name whose latter half refers to tiny, scaly leaves that resemble cedar scales. And it is saltcedar becawe the plant exudes salt &om glands on its leaves. Grab a branch, and you end up with a residue thick <I1ough to raste. When the leaves drop in the autumn, they poss that salt to the soil, which may eventually become too saline to support most mOve plant species. Given ample Wdter and space, a saltcedar can becollle a medi- um-sized tree-the l.argest known in the u.s. i~ a -I-I-foO[~r in New Mexico. In the wild, though, it more conmlOnly torl1l~ dense- thick- ets of many-branched shrubs, .aU growing to a height of 15 or 20 feet. The foliage is so dense that almost nothing call grow ullda it. Saltcedar is not really awpted [Q aridity. It grows only where water runs near the surface, and it is spendthrift-a large specimen uses perhaps 200 gallons a day. It has been e<<illlated that all the saltcedar in the Southwest uses, per year, twice .1~ much watt'[ as all the cities of southern C.alifornia. Dense stands of salt cedar trap sediment during Hoods. narrow- IIlg mter channels and perh;lps IIlcreasing tht' ~l.'\"t'ri[y of subse- quent floods. Along the CdlorJdo River, saltced.lr thickets have overgrown many be.;lches long favored for GlIllplllg ,lI1d recreJtion. Wildlife is far less abund;uH In saltcecbr thickers thall ill sup- planted native woodlands, largely because n.aUve plant<; .lCt as host [0 many more insect species. A study along the lower ColorJdo River ~howed that during the winter In undmurbed native woodland of cottonwood and wiUow sllpportt'd all average of \54 birds per 100 acres. Only 10m blr<\' lived in .n equivalent area of sahcedar. Fe\\' blrd~ nest in saltcedar. perhaps because the fe:nhery leaves do not provide the sallIe proteclion frolll illlense summer heat as do rhe broad leaves of (ot[Qll- woods and willows. It is extremely difficult [Q destroy all est.ab- lished thicket. "After any envlronmemal calamity !'.@,R, f!'!"J?"ll!C;~"."", a frrtlance writer specializing in nature and conservation topiCJ, wntB a quarterly naturt-education leaflet for the Roger Tory Peterson l"s/itute of Natural History. AMF.RICAN FORESTSJANUARY/FElm.UARY 1995..... 45