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A WEED REPORT from the book Weed Control in Natural Areas in the Western United States Saltcedar and tamarisk
<br /> in and climates during the warm season.This occurs because once the roots are within the water table they
<br /> branch profusely into numerous lateral roots to several feet long.
<br /> The inflorescences of Tamarix species consist of racemes,mostly 3 to 5 mm wide,typically simple,but
<br /> occasionally compound and panicle-like.The flowers have a nectar disc at the base which is useful for species
<br /> identification.Flowers of saltcedar,Chinese tamarisk,and French tamarisk are white,pale or dark pink,mostly
<br /> with 5 sepals,petals,and stamens.Flowers of smallflower tamarisk are typically pale to dark pink,mostly with
<br /> 4 sepals,petals,and stamens.Athel tamarisk flowers are white to pale pink,mostly with 5 sepals,petals,and
<br /> stamens.Plants all reproduce by seed,although seed production is not common in athel tamarisk,and
<br /> sometimes vegetatively from root sprouts and stem fragments.Stem fragments can take root when buried in a
<br /> moist substrate,such as might occur with a flooding event.The fruit is a small capsule,often less than 5 mm
<br /> long,with numerous minute seeds.One mature saltcedar plant can produce about 500,000 seeds per year.
<br /> Seeds disperse primarily with wind and water,and germination occurs shortly after seed dispersal in spring
<br /> through summer.Seeds lack a dormancy period,and most germinate within 24 hours after contacting water.
<br /> Seeds typically survive for only 5 weeks.Individual trees can live 75 to 100 years or more.
<br /> Although saltcedar(T.ramosissima)and Chinese tamarisk(T.chinensis)do not hybridize in their native
<br /> range,they appear to hybridize extensively in the United States.This hybrid is the most common invasive
<br /> Tamarix species from Oklahoma to Washington to California.Seed viability is high in the hybrids.Less
<br /> extensively,hybrids between saltcedar and Chinese tamarisk with smallflower tamarisk(T.paraiflora),Canary
<br /> Island tamarisk(T. canariensis)and French tamarisk(T.gallica)also occur.The abundance of invasive hybrids
<br /> may explain the confusion associated with the identification of Tamarix species in the western states.
<br /> NON-CHEMICAL CONTROL
<br /> Mechanical Mechanical control methods include mowing,burning,chopping,chaining,and disking.However,these
<br /> (pulling,cutting, methods usually only suppress saitcedar temporarily and will not eradicate infestations.Saltcedar is also
<br /> disking) able to resprout vigorously from the root crown following mechanical control methods.These methods can
<br /> be labor intensive and expensive and may be more effective on small infestations.
<br /> Hand pulling can be an effective way to control tamarisk in situations where plants are small,where access
<br /> is difficult,or where herbicides cannot be used.Hand pulling is generally used to control new Tamarix
<br /> seedlings and small plants around isolated desert springs in national parks after the larger plants have been
<br /> killed with other techniques.
<br /> Mowing is occasionally useful to reduce the volume of tamarisk before treatment with herbicide,especially
<br /> in relatively level sites where prescribed burning is not feasible.However,a single cutting of tamarisk is
<br /> ineffective,because tamarisks resprout vigorously.By comparison,cutting combined with herbicide
<br /> treatment can be a very effective integrated approach.In addition,cutting tamarisk can reduce
<br /> consumption of ground water,through removal of transpiring leaves.
<br /> Heavy equipment can be used to remove entire plants.However,this is expensive,and any fragments that
<br /> move into the water column may resprout and form new populations.This technique also causes
<br /> considerable soil disturbance and ecosystem disruption.A root plow pulled by a bulldozer has became a
<br /> standard method for saltcedar control,providing good to excellent control.Root plowing is most effective
<br /> when the soil is relatively dry and when combined with follow-up treatments such as hand grubbing
<br /> resprouts or applying herbicides.Root plowing may affect desirable vegetation and could lead to wind
<br /> erosion.Another technique uses site preparation tractors or skid steers equipped with forestry mulching
<br /> attachments,such as a hydro-ax.These are adapted to forestry brush and tree clearing.The hydro-ax can
<br /> mow or chip either living or dead saitcedar at about 1 acre/hr on level terrain.
<br /> Cultural Cattle,goats,and sheep will graze saitcedar plants if desirable vegetation is lacking.Saltcedar has little
<br /> nutritional value and cattle will only graze young seedlings early in the year.Goats might be able to control
<br /> dense stands of tamarisk where little native vegetation is present,particularly if the stands are cut or
<br /> burned first,with goats eating the regrowth.
<br /> As a stand-alone strategy,burning has not been successful.Saltcedar is generally top-killed by burning,but
<br /> plants readily resprout from the remaining root crown and adventitious buds on the lateral roots.Repeated
<br /> yearly burns can suppress saltcedar and kill some of the plants after 3 to 4 years.Furthermore,burning may
<br /> suppress saltcedar infestations by eliminating the closed canopy,slowing the rate of invasion,and allowing
<br /> desirable vegetation to respond,thereby increasing biodiversity,Prescribed burns can be followed up with
<br /> herbicide treatments to control resprouting plants.One strategy is to cut 20 to 25%of the largest tamarisk
<br /> plants in stands several months before burning to create enough dry ground fuel to carry a fire.For greatest
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