沙(sha)棗樹(shu)也(ye)叫作(zuo)桂香(xiang)(xiang)柳,產于內蒙古西(xi)部沙(sha)漠(mo)里,是沙(sha)漠(mo)的(de)(de)守護者。因開花香(xiang)(xiang)味(wei)與江南桂花相似,生命力又(you)非常頑強,故有“飄(piao)香(xiang)(xiang)沙(sha)漠(mo)的(de)(de)桂花”的(de)(de)美稱。沙(sha)棗葉片(pian)低矮,生長速度快。晚(wan)夏,滿樹(shu)花朵芳香(xiang)(xiang),還能為園林提供(gong)罕(han)見的(de)(de)銀白色景(jing)觀,也(ye)可作(zuo)為觀賞樹(shu)及背景(jing)樹(shu)。此外,沙(sha)棗樹(shu)也(ye)是很好的(de)(de)造林、綠化、薪炭、防風、固沙(sha)樹(shu)種(zhong),已成為西(xi)北(bei)地區主要造林樹(shu)種(zhong)之一。
沙棗樹屬落葉喬木(mu)或(huo)(huo)喬木(mu),高5~10米,樹干無刺,枝(zhi)條有(you)刺,刺長(chang)(chang)3~4cm,呈(cheng)紅棕色(se)(se)(se)。幼(you)枝(zhi)密被(bei)銀(yin)(yin)白(bai)(bai)色(se)(se)(se)鱗(lin)片(pian)(pian),老時脫(tuo)落,呈(cheng)栗褐色(se)(se)(se)。單葉互生,具(ju)銀(yin)(yin)白(bai)(bai)色(se)(se)(se)纖細的柄;葉片(pian)(pian)薄紙(zhi)質,長(chang)(chang)圓(yuan)狀(zhuang)披針形(xing),長(chang)(chang)3~7cm,寬(kuan)1~1.3cm,基部楔形(xing),全緣,頂端(duan)鈍尖或(huo)(huo)鈍形(xing),上面(mian)幼(you)時具(ju)銀(yin)(yin)白(bai)(bai)色(se)(se)(se)圓(yuan)形(xing)鱗(lin)片(pian)(pian),后部分脫(tuo)落,下面(mian)灰白(bai)(bai)色(se)(se)(se),密被(bei)銀(yin)(yin)白(bai)(bai)色(se)(se)(se)鱗(lin)片(pian)(pian),有(you)光澤。1~3花(hua)簇(cu)生于小枝(zhi)下部的葉腋,花(hua)萼銀(yin)(yin)白(bai)(bai)色(se)(se)(se),花(hua)瓣為金黃(huang)色(se)(se)(se)。密被(bei)銀(yin)(yin)白(bai)(bai)色(se)(se)(se)鱗(lin)片(pian)(pian),芳香;萼筒(tong)鐘(zhong)形(xing),上端(duan)4裂(lie),裂(lie)片(pian)(pian)寬(kuan)卵形(xing)或(huo)(huo)卵狀(zhuang)長(chang)(chang)圓(yuan)形(xing),內面(mian)被(bei)白(bai)(bai)色(se)(se)(se)星狀(zhuang)柔毛;雄蕊(rui)4株(zhu),幾無花(hua)絲;花(hua)柱上端(duan)彎曲,有(you)圓(yuan)錐形(xing)花(hua)盤包(bao)圍(wei)于花(hua)柱的基部。果(guo)橢(tuo)圓(yuan)形(xing),長(chang)(chang)2~3cm,直徑(jing)1~1.5cm,粉紅色(se)(se)(se)或(huo)(huo)深紅色(se)(se)(se),密被(bei)銀(yin)(yin)白(bai)(bai)色(se)(se)(se)鱗(lin)片(pian)(pian),果(guo)肉粉質,乳白(bai)(bai)或(huo)(huo)淡(dan)黃(huang)色(se)(se)(se)。花(hua)期在5~7月份,果(guo)期8~10月。生于山地、平原、沙灘(tan)、荒漠,栽(zai)培或(huo)(huo)野生。
天然沙(sha)棗只分布在降水(shui)(shui)量低(di)于150毫米(mi)(mi)的(de)(de)荒(huang)漠和半荒(huang)漠地(di)區,與淺的(de)(de)地(di)下水(shui)(shui)位相(xiang)關(guan),地(di)下水(shui)(shui)位低(di)于4米(mi)(mi),則生(sheng)長(chang)不良(liang)。沙(sha)棗側根發(fa)達,根幅很(hen)大,在疏松的(de)(de)土(tu)(tu)(tu)壤(rang)中(zhong),能生(sheng)出很(hen)多根瘤(liu)(liu),其中(zhong)的(de)(de)固氮根瘤(liu)(liu)菌(jun)還(huan)能提(ti)高土(tu)(tu)(tu)壤(rang)肥力(li),改良(liang)土(tu)(tu)(tu)壤(rang)。側枝萌發(fa)力(li)強,頂芽長(chang)勢弱。枝條(tiao)茂密(mi),常(chang)形成(cheng)稠密(mi)株叢(cong)。枝條(tiao)被沙(sha)埋(mai)后,易(yi)生(sheng)長(chang)不定根,有防風、固沙(sha)作用(yong)。
沙棗樹生(sheng)命力極強,具有抗旱、防風沙、耐(nai)鹽堿、耐(nai)貧瘠(ji)等(deng)特點。天(tian)然沙棗樹只分布(bu)在降水量低于(yu)150毫米(mi)的荒漠和(he)半(ban)荒漠地區。
作為一(yi)種喬木(mu),沙棗(zao)樹(shu)并(bing)不(bu)怎么高(gao)大,大多數只有三四(si)米(mi)高(gao),但卻是上好的(de)固沙植(zhi)物,據說(shuo)沙棗(zao)樹(shu)的(de)根系特別(bie)發(fa)達,能(neng)充分吸收沙土深層的(de)點(dian)點(dian)濕潤。因此,它不(bu)僅能(neng)在干旱(han)貧瘠的(de)沙地里生(sheng)(sheng)根發(fa)芽,茁(zhuo)壯(zhuang)成長,還(huan)能(neng)綻(zhan)放生(sheng)(sheng)命的(de)花朵,結(jie)出可愛的(de)果子。
沙(sha)棗(zao)樹果實(沙(sha)棗(zao))于(yu)10月中下旬成(cheng)熱。果實成(cheng)熟后并(bing)不立即脫(tuo)(tuo)落(luo),可用手摘取或以(yi)竿擊落(luo),布(bu)幕收集。采(cai)種(zhong)(zhong)(zhong)要(yao)選(xuan)擇生長(chang)健壯,無病(bing)蟲害、樹干較(jiao)通直、果實品(pin)質好的(de)母(mu)樹。果實采(cai)回后及時攤曬,防(fang)止發(fa)霉,干后用石碾(nian)碾(nian)壓,脫(tuo)(tuo)除果面。100斤(jin)果實,約可出種(zhong)(zhong)(zhong)子(zi)50斤(jin),沙(sha)棗(zao)面50斤(jin)。種(zhong)(zhong)(zhong)子(zi)在干燥通風(feng)處貯藏,堆層厚度(du)不宜超過1米。新鮮(xian)飽(bao)滿(man)的(de)種(zhong)(zhong)(zhong)子(zi)發(fa)芽率(lv)多(duo)在90%以(yi)上,貯存良好的(de)種(zhong)(zhong)(zhong)子(zi),5~6年后,發(fa)芽率(lv)仍達(da)60~70%。種(zhong)(zhong)(zhong)子(zi)的(de)重(zhong)量因(yin)品(pin)種(zhong)(zhong)(zhong)而(er)不同,種(zhong)(zhong)(zhong)子(zi)千粒重(zhong)為(wei)250~380克,每(mei)斤(jin)有種(zhong)(zhong)(zhong)子(zi)1300~2000粒。
播種育苗
播(bo)(bo)(bo)種(zhong)(zhong)(zhong)(zhong)育苗(miao)(miao)多在春(chun)季。春(chun)季育苗(miao)(miao)的(de)(de)要在頭年冬(dong)季12月進行種(zhong)(zhong)(zhong)(zhong)子(zi)處(chu)理(li)。方法(fa)是把種(zhong)(zhong)(zhong)(zhong)子(zi)淘洗(xi)干(gan)凈(jing),摻等量細沙混和均(jun)勻,放(fang)入事(shi)先(xian)挖好的(de)(de)種(zhong)(zhong)(zhong)(zhong)子(zi)處(chu)理(li)坑(深80厘(li)米(mi)(mi)(mi)(mi),寬100厘(li)米(mi)(mi)(mi)(mi),長(chang)隨種(zhong)(zhong)(zhong)(zhong)子(zi)多少而定)內,或(huo)按(an)40~60厘(li)米(mi)(mi)(mi)(mi)厚堆(dui)放(fang)地面,周(zhou)圍用(yong)沙壅埋成埂,灌足水(種(zhong)(zhong)(zhong)(zhong)子(zi)上面積水10~20厘(li)米(mi)(mi)(mi)(mi)),待水滲下或(huo)結冰后,覆(fu)沙20厘(li)米(mi)(mi)(mi)(mi)越冬(dong)。未經冬(dong)藏(zang)的(de)(de)種(zhong)(zhong)(zhong)(zhong)子(zi),播(bo)(bo)(bo)前(qian)可(ke)(ke)用(yong)50~60℃溫水浸泡2~3天,撈出后與馬糞混和放(fang)在向陽處(chu)保濕催(cui)芽,待30~40%種(zhong)(zhong)(zhong)(zhong)子(zi)裂嘴后即可(ke)(ke)播(bo)(bo)(bo)種(zhong)(zhong)(zhong)(zhong)。秋(qiu)播(bo)(bo)(bo)的(de)(de)種(zhong)(zhong)(zhong)(zhong)子(zi)不必催(cui)芽處(chu)理(li)。沙棗樹育苗(miao)(miao)可(ke)(ke)用(yong)大田式(shi)條播(bo)(bo)(bo),行距25厘(li)米(mi)(mi)(mi)(mi),播(bo)(bo)(bo)種(zhong)(zhong)(zhong)(zhong)深度3~5厘(li)米(mi)(mi)(mi)(mi),每(mei)(mei)米(mi)(mi)(mi)(mi)常播(bo)(bo)(bo)種(zhong)(zhong)(zhong)(zhong)溝播(bo)(bo)(bo)種(zhong)(zhong)(zhong)(zhong)100粒左(zuo)右,每(mei)(mei)畝下種(zhong)(zhong)(zhong)(zhong)40斤左(zuo)右,播(bo)(bo)(bo)后覆(fu)土,6月上旬間苗(miao)(miao),苗(miao)(miao)距7厘(li)米(mi)(mi)(mi)(mi),每(mei)(mei)畝保苗(miao)(miao)3~4萬(wan)株(zhu)。當(dang)年生(sheng)苗(miao)(miao)高(gao)50~60厘(li)米(mi)(mi)(mi)(mi),可(ke)(ke)出圃造林。
扦插育苗
沙棗樹扦插育苗(miao)能保持(chi)母株的優良品質(zhi):插條剪取、扦插方法、時間等都與楊樹扦插相同(tong),詳(xiang)見二白楊扦插育苗(miao)。
沙棗樹可用(yong)植苗或插干造(zao)林(lin)
插干造林
在土(tu)壤濕潤、水分條件好(hao)(hao)的地方,可用插(cha)干造(zao)林。選擇2厘米(mi)粗,1.5米(mi)長的枝條,剪去(qu)側(ce)枝后(hou)作為側(ce)穗,直(zhi)接插(cha)于整好(hao)(hao)地的造(zao)林地上,扦插(cha)深度一般應達40厘米(mi)。以春季扦插(cha)為好(hao)(hao)。插(cha)后(hou)要保(bao)持土(tu)壤濕潤。
植苗造林
植(zhi)苗(miao)造林(lin)可在春,秋(qiu)(qiu)兩季進行,春季為“清明”至(zhi)“谷雨”,秋(qiu)(qiu)季為“霜(shuang)降(jiang)”至(zhi)“立(li)冬”,但以春季造林(lin)為好。在地(di)(di)下水位不超過(guo)(guo)2~3米的沙荒灘(tan)地(di)(di)或(huo)丘間(jian)低地(di)(di)上造林(lin),不灌水也(ye)能成活、生長。若地(di)(di)下水位過(guo)(guo)深時,需有(you)灌溉條件方可造林(lin)。土(tu)壤(rang)粘重(zhong)的,要在頭年耕翻整地(di)(di),來年造林(lin),沙壤(rang)土(tu)、壤(rang)質沙土(tu)地(di)(di)、厚覆沙地(di)(di)以及地(di)(di)表(biao)鹽(yan)結皮(pi)較厚的鹽(yan)漬土(tu),都可邊挖穴邊栽(zai)植(zhi),不必事先(xian)整地(di)(di)。每(mei)畝栽(zai)植(zhi)200株左(zuo)右。