金絲(si)柳(學名(ming):Salix alba 'Tristis')是楊(yang)柳科、柳屬(shu)喬(qiao)(qiao)木(mu)(mu),落葉喬(qiao)(qiao)木(mu)(mu),高達可達15米,小枝呈金黃色(se)(se),光(guang)亮,細長下垂(chui)。葉片(pian)狹長披針形,樹皮灰(hui)黑色(se)(se),不規則開(kai)裂;芽(ya)線形,先(xian)端急尖(jian)。上面綠色(se)(se),下面色(se)(se)較(jiao)淡,鋸齒緣;葉柄有短柔(rou)毛;花(hua)序(xu)先(xian)葉開(kai)放,雄(xiong)花(hua)序(xu)有短梗(geng),軸(zhou)有毛;花(hua)絲(si)與(yu)苞片(pian)近等長或較(jiao)長,花(hua)藥紅黃色(se)(se);苞片(pian)披針形,雌花(hua)序(xu)有梗(geng),子房橢圓形,花(hua)柱(zhu)短,蒴果(guo)帶綠黃褐色(se)(se)。3-4月開(kai)花(hua),4-5月結果(guo)。
中國北方城市有(you)引種(zhong)栽培。金絲柳喜光,耐寒、耐濕(shi),也具(ju)有(you)一定的耐旱性(xing),在(zai)多數土(tu)壤條件下都能夠(gou)很(hen)好的生長。對于鹽堿(jian)、水淹都有(you)較強的耐受性(xing),河邊(bian)水岸、湖泊灘涂、鹽堿(jian)地也適合(he)金絲柳的生長。
金(jin)(jin)絲柳(liu)樹(shu)干和枝條(tiao)曲折(zhe)盤旋(xuan),葉(xie)片、枝葉(xie)都為黃色,樹(shu)形(xing)優(you)美,春天不飛花絮,發(fa)芽(ya)較早,落葉(xie)相(xiang)對較晚,是一種極具觀賞性(xing)的(de)樹(shu)種。金(jin)(jin)絲柳(liu)在(zai)有(you)水的(de)地方也能很好的(de)生(sheng)長,萌芽(ya)強(qiang),生(sheng)長快,特(te)別適合在(zai)河(he)岸、湖邊、池畔栽植(zhi),是一種優(you)良(liang)的(de)園(yuan)林綠化樹(shu)種,也是庭院中(zhong)主(zhu)要的(de)觀賞樹(shu)種。
中國(guo)北方城(cheng)市有引種(zhong)栽培(pei)。金絲(si)柳(liu)喜(xi)光,耐寒(han)、耐濕,也具有一(yi)定的(de)(de)(de)耐旱性,在多數(shu)土(tu)壤條(tiao)件(jian)下都(dou)能夠很好(hao)的(de)(de)(de)生(sheng)長(chang),是(shi)一(yi)種(zhong)適(shi)應性較(jiao)強(qiang)的(de)(de)(de)樹種(zhong)。對(dui)于(yu)鹽堿、水(shui)淹都(dou)有較(jiao)強(qiang)的(de)(de)(de)耐受(shou)性,河(he)邊水(shui)岸(an)、湖泊灘涂(tu)、鹽堿地都(dou)可栽植(zhi),特別是(shi)一(yi)些濕潤且排(pai)水(shui)較(jiao)好(hao)的(de)(de)(de)土(tu)壤非常(chang)適(shi)合(he)金絲(si)柳(liu)的(de)(de)(de)生(sheng)長(chang)。
落葉喬木,高達6-15米,小枝(zhi)呈金黃(huang)色(se),光亮(liang),細長(chang)下垂。葉狹(xia)長(chang)披針形(xing),樹冠開展(zhan)而(er)疏散。樹皮灰黑色(se),不規則開裂(lie);無毛(mao)(mao)。芽線形(xing),先端急(ji)尖(jian)。葉片長(chang)9-16厘(li)米,寬0.5-1.5厘(li)米,先端長(chang)漸尖(jian),基(ji)部(bu)楔(xie)形(xing)兩面(mian)無毛(mao)(mao)或微有毛(mao)(mao),上(shang)(shang)面(mian)綠色(se),下面(mian)色(se)較淡,鋸齒緣;葉柄長(chang)(3)5-10毫米,有短柔毛(mao)(mao);托葉僅生(sheng)在萌發枝(zhi)上(shang)(shang),斜(xie)披針形(xing)或卵(luan)圓(yuan)形(xing),邊(bian)緣有齒牙(ya)。
花(hua)序(xu)先葉(xie)開放,或(huo)(huo)(huo)與葉(xie)同時開放;雄花(hua)序(xu)長(chang)1.5-2(3)厘(li)米(mi),有(you)(you)(you)短梗(geng),軸(zhou)有(you)(you)(you)毛(mao);雄蕊2,花(hua)絲與苞(bao)片(pian)近等長(chang)或(huo)(huo)(huo)較長(chang),基(ji)部(bu)(bu)多少有(you)(you)(you)長(chang)毛(mao),花(hua)藥紅黃(huang)色;苞(bao)片(pian)披針形(xing),外面有(you)(you)(you)毛(mao);腺(xian)體2;雌(ci)花(hua)序(xu)長(chang)達2-3(5)厘(li)米(mi),有(you)(you)(you)梗(geng),基(ji)部(bu)(bu)有(you)(you)(you)3-4小葉(xie),軸(zhou)有(you)(you)(you)毛(mao);子房橢圓形(xing),無毛(mao)或(huo)(huo)(huo)下部(bu)(bu)稍(shao)有(you)(you)(you)毛(mao),無柄或(huo)(huo)(huo)近無柄,花(hua)柱短,柱頭2-4深裂(lie);苞(bao)片(pian)披針形(xing),長(chang)約1.8-2(2.5)毫米(mi),外面有(you)(you)(you)毛(mao);腺(xian)體1。蒴果長(chang)3-4毫米(mi),帶綠黃(huang)褐色。花(hua)期3-4月(yue),果期4-5月(yue)。
金(jin)絲種植(zhi)(zhi)要(yao)通(tong)過移(yi)(yi)(yi)植(zhi)(zhi)苗(miao)木(mu)進行(xing)(xing)(xing),移(yi)(yi)(yi)植(zhi)(zhi)要(yao)選擇合適的(de)苗(miao)木(mu)進行(xing)(xing)(xing)定植(zhi)(zhi),地塊宜(yi)選擇在濕潤(run)、土(tu)(tu)壤(rang)肥(fei)(fei)沃的(de)地方(fang)。移(yi)(yi)(yi)植(zhi)(zhi)前(qian)要(yao)施足(zu)基肥(fei)(fei),密度控制在250株(zhu)/畝,植(zhi)(zhi)行(xing)(xing)(xing)距可以為2米,也可以為1.5米。移(yi)(yi)(yi)植(zhi)(zhi)宜(yi)早不宜(yi)遲,一般以休眠期移(yi)(yi)(yi)植(zhi)(zhi)好(hao),基本(ben)在每年的(de)春季(ji)化凍之(zhi)前(qian),苗(miao)木(mu)尚未(wei)萌(meng)動(dong)時移(yi)(yi)(yi)植(zhi)(zhi),先挖好(hao)移(yi)(yi)(yi)植(zhi)(zhi)穴,大苗(miao)要(yao)帶土(tu)(tu)移(yi)(yi)(yi)植(zhi)(zhi),入(ru)穴后蓋(gai)好(hao)土(tu)(tu),同(tong)時要(yao)澆足(zu)定根(gen)水(shui),在管理期要(yao)做好(hao)清溝和(he)培(pei)土(tu)(tu)工作(zuo)。
除(chu)草(cao)(cao)是(shi)(shi)金絲(si)柳種植管理中重要(yao)(yao)的(de)(de)一項工(gong)作,由于(yu)初期金絲(si)柳的(de)(de)長(chang)勢不強,很容易受到雜草(cao)(cao)的(de)(de)影(ying)響,在(zai)水分(fen)和(he)養分(fen)等(deng)方(fang)面進行(xing)(xing)(xing)(xing)(xing)(xing)爭奪,所以(yi)(yi)要(yao)(yao)及時進行(xing)(xing)(xing)(xing)(xing)(xing)雜草(cao)(cao)清除(chu),結合松(song)土(tu),一般在(zai)灌溉和(he)降雨后(hou)(hou)進行(xing)(xing)(xing)(xing)(xing)(xing),成林要(yao)(yao)連續3-5年(nian)(nian)(nian)(nian)進行(xing)(xing)(xing)(xing)(xing)(xing)除(chu)草(cao)(cao)松(song)土(tu),每(mei)(mei)(mei)年(nian)(nian)(nian)(nian)要(yao)(yao)進行(xing)(xing)(xing)(xing)(xing)(xing)2-3次,在(zai)松(song)土(tu)和(he)除(chu)草(cao)(cao)的(de)(de)過(guo)程中,要(yao)(yao)注意尺度(du),避免傷(shang)(shang)到樹(shu)(shu)木根(gen)部。施(shi)(shi)(shi)(shi)肥(fei)(fei)(fei)(fei)可(ke)(ke)以(yi)(yi)分(fen)基(ji)肥(fei)(fei)(fei)(fei)和(he)追肥(fei)(fei)(fei)(fei)兩種形(xing)式(shi)進行(xing)(xing)(xing)(xing)(xing)(xing),基(ji)肥(fei)(fei)(fei)(fei)主要(yao)(yao)是(shi)(shi)以(yi)(yi)有(you)機肥(fei)(fei)(fei)(fei)為主,春秋都可(ke)(ke)以(yi)(yi)施(shi)(shi)(shi)(shi)用(yong)(yong)(yong)(yong)(yong),一般以(yi)(yi)秋施(shi)(shi)(shi)(shi)效果較好(hao),幼樹(shu)(shu)期每(mei)(mei)(mei)年(nian)(nian)(nian)(nian)畝用(yong)(yong)(yong)(yong)(yong)3600千克(ke)的(de)(de)基(ji)肥(fei)(fei)(fei)(fei),隨(sui)著樹(shu)(shu)的(de)(de)長(chang)大(da),三年(nian)(nian)(nian)(nian)以(yi)(yi)后(hou)(hou)每(mei)(mei)(mei)年(nian)(nian)(nian)(nian)要(yao)(yao)增加到每(mei)(mei)(mei)畝5000千克(ke)基(ji)肥(fei)(fei)(fei)(fei),可(ke)(ke)以(yi)(yi)采用(yong)(yong)(yong)(yong)(yong)行(xing)(xing)(xing)(xing)(xing)(xing)間溝(gou)(gou)(gou)施(shi)(shi)(shi)(shi)入的(de)(de)方(fang)法進行(xing)(xing)(xing)(xing)(xing)(xing)施(shi)(shi)(shi)(shi)用(yong)(yong)(yong)(yong)(yong)基(ji)肥(fei)(fei)(fei)(fei)。追肥(fei)(fei)(fei)(fei)則(ze)以(yi)(yi)化肥(fei)(fei)(fei)(fei)和(he)復合肥(fei)(fei)(fei)(fei)為主,每(mei)(mei)(mei)年(nian)(nian)(nian)(nian)施(shi)(shi)(shi)(shi)肥(fei)(fei)(fei)(fei)2-3次,宜在(zai)每(mei)(mei)(mei)年(nian)(nian)(nian)(nian)樹(shu)(shu)木生(sheng)長(chang)期前(5月)和(he)生(sheng)長(chang)高峰(feng)期(6月、7月)進行(xing)(xing)(xing)(xing)(xing)(xing)。以(yi)(yi)尿素為例,前三年(nian)(nian)(nian)(nian),每(mei)(mei)(mei)年(nian)(nian)(nian)(nian)每(mei)(mei)(mei)株施(shi)(shi)(shi)(shi)用(yong)(yong)(yong)(yong)(yong)量150-400克(ke),第四年(nian)(nian)(nian)(nian)后(hou)(hou),每(mei)(mei)(mei)年(nian)(nian)(nian)(nian)每(mei)(mei)(mei)株施(shi)(shi)(shi)(shi)用(yong)(yong)(yong)(yong)(yong)500-1000克(ke),對于(yu)幼樹(shu)(shu)使用(yong)(yong)(yong)(yong)(yong)環狀溝(gou)(gou)(gou)施(shi)(shi)(shi)(shi),在(zai)樹(shu)(shu)冠垂(chui)(chui)直投(tou)影(ying)外(wai)圍(wei)稍(shao)遠處挖環狀施(shi)(shi)(shi)(shi)肥(fei)(fei)(fei)(fei)溝(gou)(gou)(gou),進行(xing)(xing)(xing)(xing)(xing)(xing)施(shi)(shi)(shi)(shi)肥(fei)(fei)(fei)(fei)。大(da)樹(shu)(shu)多用(yong)(yong)(yong)(yong)(yong)放(fang)射(she)溝(gou)(gou)(gou)施(shi)(shi)(shi)(shi),即(ji)以(yi)(yi)樹(shu)(shu)干為中心,在(zai)樹(shu)(shu)干至樹(shu)(shu)冠垂(chui)(chui)直投(tou)影(ying)外(wai)圍(wei)1/2處為起點(dian)向外(wai)開挖放(fang)射(she)狀溝(gou)(gou)(gou),溝(gou)(gou)(gou)長(chang)超過(guo)樹(shu)(shu)冠垂(chui)(chui)直投(tou)影(ying)外(wai)圍(wei),要(yao)(yao)里淺外(wai)深,避免傷(shang)(shang)根(gen)。
金絲柳是喜光喜水(shui)的樹(shu)(shu)(shu)種(zhong)(zhong),一(yi)(yi)般苗(miao)木栽植(zhi)后(hou)(hou),要及時(shi)澆(jiao)水(shui),基本上(shang)(shang)每7天就要澆(jiao)一(yi)(yi)次透水(shui),連(lian)續澆(jiao)3-4次,這樣才(cai)能確(que)保(bao)苗(miao)木成活。苗(miao)木成活后(hou)(hou)進入生(sheng)長(chang)期,以(yi)后(hou)(hou)要關注(zhu)土壤墑(di)情(qing)(qing),視情(qing)(qing)況進行(xing)適(shi)當(dang)補水(shui),一(yi)(yi)般進入雨(yu)季(ji)后(hou)(hou),也就是6月份以(yi)后(hou)(hou),可(ke)以(yi)適(shi)當(dang)減少(shao)澆(jiao)水(shui)次數。秋季(ji)樹(shu)(shu)(shu)木落葉(xie)后(hou)(hou),上(shang)(shang)凍(dong)前要澆(jiao)一(yi)(yi)次封凍(dong)水(shui)。幼樹(shu)(shu)(shu)階段(duan),要結合土壤墑(di)情(qing)(qing)及降水(shui)情(qing)(qing)況來確(que)定(ding)澆(jiao)水(shui)與否,一(yi)(yi)般每年澆(jiao)4-6次便可(ke)以(yi)滿足需要。苗(miao)期和幼樹(shu)(shu)(shu)階段(duan),種(zhong)(zhong)植(zhi)地內(nei)都不能長(chang)期積(ji)水(shui),因為(wei)此(ci)時(shi)苗(miao)木根系尚不發達,還沒(mei)有較(jiao)強的耐積(ji)水(shui)能力,發現積(ji)水(shui)要及時(shi)排掉。
修(xiu)(xiu)剪整形(xing)也是金絲柳(liu)管理中的(de)(de)一(yi)個重要(yao)(yao)環節,一(yi)般在秋季或春季進(jin)行(xing),秋季整形(xing)要(yao)(yao)在落葉后,春季要(yao)(yao)在萌動前。幼樹郁閉前一(yi)般不進(jin)行(xing)整形(xing)修(xiu)(xiu)剪,但要(yao)(yao)根據(ju)具體情況,如果(guo)側枝(zhi)生長過(guo)(guo)強(qiang),影響(xiang)到主枝(zhi)的(de)(de)生長而要(yao)(yao)進(jin)行(xing)適當(dang)剪去一(yi)些側枝(zhi),以促(cu)進(jin)主干的(de)(de)生長。林木郁閉后,要(yao)(yao)進(jin)行(xing)修(xiu)(xiu)枝(zhi),修(xiu)(xiu)枝(zhi)要(yao)(yao)注(zhu)意不能過(guo)(guo)多,要(yao)(yao)確(que)保修(xiu)(xiu)后冠高不能低于樹高的(de)(de)一(yi)半。
金絲(si)柳的(de)(de)扦(qian)插(cha)(cha)(cha)一(yi)(yi)般在(zai)每年(nian)的(de)(de)春季進(jin)(jin)(jin)行,中(zhong)國(guo)北方地區多數在(zai)3-4月化(hua)凍后(hou)(hou)(hou)便可(ke)以(yi)進(jin)(jin)(jin)行。首先要(yao)進(jin)(jin)(jin)行插(cha)(cha)(cha)穗(sui)的(de)(de)剪取(qu),選擇長勢(shi)健壯、無病蟲(chong)害的(de)(de)母(mu)樹枝(zhi)條(tiao)(tiao),選一(yi)(yi)年(nian)生枝(zhi)條(tiao)(tiao)做插(cha)(cha)(cha)穗(sui),選好(hao)枝(zhi)條(tiao)(tiao)后(hou)(hou)(hou),剪下來(lai)然后(hou)(hou)(hou)分成幾段(duan)截取(qu),每段(duan)15厘米(mi)(mi),然后(hou)(hou)(hou)按照上、中(zhong)、下不同(tong)部位(wei)的(de)(de)插(cha)(cha)(cha)穗(sui)進(jin)(jin)(jin)行分級捆扎(zha),每扎(zha)50根(gen),如果不立即(ji)扦(qian)插(cha)(cha)(cha)則進(jin)(jin)(jin)行假植。育苗地的(de)(de)選取(qu)要(yao)盡(jin)可(ke)能選擇地勢(shi)平坦,排水灌水條(tiao)(tiao)件較好(hao),土(tu)層(ceng)深(shen)厚(hou),相對疏松的(de)(de)沙質(zhi)土(tu)或壤土(tu)來(lai)做苗地,選好(hao)后(hou)(hou)(hou)要(yao)進(jin)(jin)(jin)行翻耕(geng),耕(geng)深(shen)在(zai)25厘米(mi)(mi)左右,同(tong)時(shi)要(yao)進(jin)(jin)(jin)行施肥(fei)(fei)(fei),畝用有機肥(fei)(fei)(fei)2000千(qian)克(ke),復合(he)(he)肥(fei)(fei)(fei)50千(qian)克(ke),結合(he)(he)翻耕(geng)將肥(fei)(fei)(fei)料均勻(yun)混合(he)(he)到(dao)土(tu)壤中(zhong)。在(zai)插(cha)(cha)(cha)之前,要(yao)提前3天(tian)把插(cha)(cha)(cha)穗(sui)放在(zai)清水中(zhong)浸泡,使插(cha)(cha)(cha)穗(sui)吸足水分,然后(hou)(hou)(hou)進(jin)(jin)(jin)行插(cha)(cha)(cha)條(tiao)(tiao),可(ke)以(yi)直(zhi)插(cha)(cha)(cha),也(ye)可(ke)以(yi)傾斜插(cha)(cha)(cha),插(cha)(cha)(cha)后(hou)(hou)(hou)要(yao)及時(shi)澆(jiao)透(tou)水,一(yi)(yi)般幼(you)苗在(zai)生根(gen)之前,要(yao)澆(jiao)1-2次透(tou)水,以(yi)后(hou)(hou)(hou)每隔(ge)2周澆(jiao)一(yi)(yi)次,基本到(dao)4月中(zhong)下旬,插(cha)(cha)(cha)穗(sui)便會生出幼(you)根(gen),這(zhe)時(shi)要(yao)及時(shi)進(jin)(jin)(jin)行補肥(fei)(fei)(fei),畝用化(hua)肥(fei)(fei)(fei)10千(qian)克(ke),以(yi)后(hou)(hou)(hou)每隔(ge)6周施一(yi)(yi)次肥(fei)(fei)(fei),前期(qi)以(yi)氮(dan)肥(fei)(fei)(fei)為(wei)主,后(hou)(hou)(hou)期(qi)適當(dang)補加磷(lin)鉀肥(fei)(fei)(fei),通過營養補充促(cu)進(jin)(jin)(jin)樹苗的(de)(de)生長及根(gen)系的(de)(de)發育。
金絲柳樹干和枝(zhi)條曲折盤旋,葉片、枝(zhi)葉都為(wei)黃色,樹形(xing)優美,春天不飛花絮,發芽較早,落葉相對較晚(wan),是一種極具觀(guan)賞性(xing)的樹種。金絲柳在有水的地方也能很(hen)好的生長(chang),萌(meng)芽強,生長(chang)快,特別適合在河岸、湖(hu)邊、池畔栽植(zhi),是一種優良的園林綠化樹種,也是庭院(yuan)中(zhong)主要的觀(guan)賞樹種。