矮化剂在草坪上的应用试验

草坪的养护主要包括浇水、施肥、修剪等内容，据测算，草坪修剪费用的占草坪管理直接成本费用3/5左右，因此，怎样使草坪少剪甚至不剪，是降低草坪养护成本的关键。多效唑的矮化机理主要是作用于叶片，通过叶片吸收抑制植株生长，叶片变短，节间缩短。草坪矮化剂（吉林市昌邑区花卉研究所生产）主要作用于植株根部，达到抑制草坪生长，减少修剪次数。1试验材料和方法试验地位于克拉玛依市朝阳公园内，为早熟禾与高羊茅的混播草坪。选用15%多效唑和草坪矮化剂两种试验材料喷施草坪，喷施药剂前修剪草坪，修剪平均高度5．５cm，每种试验材料分…     

高羊茅草坪不同播种量对比试验研究

为了解决高羊茅冷季型草种在武汉安全越夏的问题,进行了高羊茅草坪不同播种量对比试验,结果表明：一级质量的种子(发芽率85%以上)播种量以15～25g/m~2为宜,20g/m~2最好,有利于草坪生长及安全越夏。     

郑州市泛建冷地型草坪的问题及对策

近几年 ,郑州市大面积引种推广冷地型草坪 ,主要种植种类有早熟禾、羊茅、黑麦草、剪股颖 ,其中以草地早熟禾 ,如亨特、午夜、格莱得、高羊茅、紫羊茅 ,多年生黑麦草、细弱剪股颖最为广泛。目前郑州市已有冷地型草坪2 0 0多万ｍ2 ,仅道路绿化就达 80万ｍ2 。这些草坪在改善城市绿色景观方面的作用令人瞩目 ,但随着大量地建植 ,出现了以下问题 :1　需水量大 ,修剪次数多冷地型草对水分要求较高 ,5～ 1 0月这半年时间内 ,由于郑州市气候干燥、高温 ,需3～ 5天浇 1次透水 ,否则就会出现旱象。由于浇水跟不上 ,现已有很多草坪出现大片死亡。大量…     

冷季型观赏草坪草引种比较试验

对引进的高羊茅、黑麦草、早熟禾等3大类13个冷季型草坪草品种的栽培性状观察结果表明：(1)在矮化、窄叶、均密等观赏草坪评价指标上，黑麦草优于高羊茅。(2)播种期对植株分蘖数和叶宽等性状的影响：春播(4-5月)与秋播(9～10月)呈5％显著水平差异。(3)在常规贮藏条件下，贮藏期对种子生活力的影响：越冬贮藏不显著，而越夏贮藏后的种子生活力下降显著，其中高羊茅下降64．3％、早熟禾下降47．4％、黑麦草下降20．3％，且均达5％显著水平差异。     

高羊茅草坪不同土壤基质对比试验研究

为了解决高羊茅冷季型草种在武汉安全越夏的问题,进行了高羊茅草坪不同土壤基质对比试验。结果表明:黄粘土、河沙因过粘或沙性过重均不利于草坪生长,降低抗逆性,黄粘土与河沙按40%~60%混合,改良效果好。     

绿地的养护措施

1、公共绿地草坪管理　　日常管理包括修剪和施肥，草坪的修剪一年最少4～5次采用机械修剪，用机械施化肥为好，在北方干旱、半干旱地区根据需要可考虑安装地埋式喷灌系统，大型专业草坪广场一年中要修剪上百次。　　2、森林（包括郊野、体育、文化、娱乐等）公园草坪管护　　草坪应做到及时修剪、施肥、浇水。体育场草坪修剪要低矮、致密、平滑，抗践踏和具有较强的恢复力。一般修剪高度为1．25～2．5cm，赛季草坪修剪高度不应低于3cm。多赛事的季节可适当提高修剪高度。塞前和比赛期间均可施肥。比赛前几周每公顷可施肥45kg速效氮或90～18…     

适合于呼市地区生长的几种草坪

呼市地区目前主要以冷季型草坪的早熟禾属和羊茅属中的草坪品种为主 ,我们经过三年对早熟禾 ,羊茅属中的部分草坪的种植试验和观察 ,总结出早熟禾属中的那苏、肯塔基、羊茅属中的紫羊茅更适合于华北地区的种植生长。一、试验方法 :通过对早熟禾属中的巴润、优异、那苏、康尼、肯塔基和羊茅属中的紫羊茅、羊茅分别以１０平方米面积为单元 ,对水、肥、修剪、越冬、越夏、践踏、抗性、绿色期等方面的单因子和多因子的田间试验不同措施的管理及观察得出结论 ,主要通过以下几组表格进行比较。二、结果分析 :通过以上几组测试表格的分析 ,总结出最…     

过渡带地区高羊茅草坪的养护管理

高羊茅属冷季型草,是长江中下游地区(草坪过渡气候带)条件下一种重要草坪。它较之其它冷季型草坪如多年生黑麦草、早熟禾等,适应性和抗性均优,在养护管理措施得当的情况下可基本做到四季常绿。高羊茅色泽深,成坪快,具良好的耐践踏能力,夏季能耐高温、干旱,抗病虫害能力较强,耐修剪。我们在上海、江苏、江西、湖南等地建坪养护均获成功,使高羊茅草坪达到了四季常绿。一、水分管理高羊茅草坪夏季水分管理尤为重要。当白天温度高于30℃,夜间温度高于20℃时,水分管理不当极易引发病害,甚至导致高羊茅草坪的成片死亡。一般要求每天早晨10时以前进…     

高羊茅草坪不同品种对比试验研究

为了解决高羊茅冷季型草种在武汉安全越夏的问题,进行了Houndog、Arid、Barlexal等高羊茅品种单播及品种混播试验,结果表明:Houndog、Shenandon、Barlexal、Arid品种在本地区越夏情况表现较好。Arid+shenandon、Houndog+Shenandon等比例混合播种,其草坪抗病性比单播的明显增强。     

模拟酸雨对4种草坪草幼苗生理特性影响

为了探究不同草坪草在酸雨胁迫下幼苗生长的能力,给今后酸雨灾害地区园林地被植物的选择提供参考依据,以多年生黑麦草、高羊茅、匍匐剪股颖、草地早熟禾等4种草坪草为试验材料,采用不同pH(pH=3、pH=4、pH=5)的模拟酸雨处理,对其叶片形态、伤害指标、保护酶活性及渗透调节物质含量等指标进行测定,并用模糊数学隶属度进行综合评价。结果表明:4种草坪草对酸雨抗性能力从强到弱排序是高羊茅(0.824)、多年生黑麦草(0.601)、匍匐剪股颖(0.435)、草地早熟禾(0.430)。     

不同修枝强度对托里桉幼林生长的影响

对3年生托里桉进行修枝试验,修枝强度为修去4种树干直径5cm,6cm,7cm和8cm以下所有枝条.修枝7个月后对试验地进行测量并分析,结果表明：修枝木的树高、胸径、冠幅以及单株材积均随着修枝强度的增大而相应变小。适当修枝有利于托里桉幼林的生长,建议采用8cm强度进行修枝。     

思茅松嫩枝扦插穗条培养研究

2006年在普洱市林业科学研究所苗圃内进行思茅松采穗母株的定植密度、修剪高度、施肥量对产穗量的影响试验.结果表明,穗条培养产穗量较高的模式为:株行距为40 cm×40 cm,修剪高度为10 cm,施肥量为20 g/株.     

桤木采穗圃无性系树体管理试验

通过对桤木无性系采穗圃植株主干定干高度、枝条修剪强度等试验研究表明：无性系植株的嫩枝总芽数与无性系植株定干高度及枝条修剪强度等密切相关.建立桤木无性系采穗圃,无性系植株定干高度以90 cm为宜,且无性系枝条宜采用轻短截,这样既可提高无性系植株嫩枝总芽数,又扩大树冠,增强树势,保证采穗圃插穗的高产稳产.     

杉木人工林无节材培育技术研究

采用目标树培育技术,通过人工修枝的方法来培育杉木人工林无节木材,以提高南方杉木木材的市场价值。为了形成一套较为完整的杉木无节材培育技术,按照不同的保留密度和修枝强度等因素进行试验设计。根据1999—2003年连续4 a的观测数据,分析结果表明,杉木8年生前林分的保留密度对杉木生长无显著影响,在1 800株.hm-2范围内可以采用较大的保留密度;不同的修枝强度对杉木生长造成显著影响,随着修枝强度的增大,杉木的树高、胸径和冠幅生长都显著下降,考虑到修枝效果和杉木生长两方面因素,以10 cm的修枝强度(修枝的基础粗度)最好。     

落叶松人工林整枝研究

根据落叶松人工林不同林龄的10块样地50棵树的节子数据和19块样地95棵树的圆盘数据,建立树高曲线模型、有效冠高的预估模型、林龄与死枝高度的曲线模型,各模型的判定系数均大于0.8,检验精度均大于95%。根据节子高度中的最低节子高度的平均值确定落叶松人工林的整枝起始高度（h1）,用林龄与死枝高度的曲线模型计算该高度上的枝条死亡的时间（t1）为起始整枝时间,t1=14 a。整枝的间隔时间随着林龄的增加先增大,当林龄达在40 a时开始减小。整枝强度也是随林龄的增加先增大,当林龄达到40 a时开始下降,说明林龄在35~40 a是该落叶松人工林生长最旺盛的时期,在这段时期可以考虑该落叶松人工林的主伐问题。当林龄达到47 a后,整枝强度降到1m以下。     

修枝对华北落叶松人工林分生长的初期影响

以河北省围场县木兰林管局管辖区的新丰林场试验林为基础,分析了修枝强度以及修枝剩余物的不同处理对华北落叶松人工林生长及冠层变化的影响。修枝强度设置3种,强(冠高比4/5)、中(冠高比7/10)、弱(冠高比3/5);对修枝剩余物处理分别为放置、清理、粉碎,并设置对照。结果表明:不同程度的修枝对林木的胸径生长率均有一定的提高作用,其中,中度修枝对林木胸径、树高生长率的促进和Vissky系数的提高较为明显;针对修枝剩余物不同处理试验的初期结果显示,粉碎处理和清理处理的林分,有利于林木胸径生长率的提高,放置处理的林分更有利于提高林木树高生长率。     

火炬松纸浆材优良家系人工林修枝效应

对7 a生火炬松优良家系(L—11)示范林进行修枝试验表明:修枝促进了林分生长,修枝3 a后,与对照相比树高生长增加了7．1％～14．1％,胸径生长增加了1．9％～7．4％,单株材积增加了9．98％-29．10％,林分蓄积量增加12．13-26．53 m3／hm2,其中促进林分生长效果最好的处理是修枝强度为50％;修枝降低了火炬松优良家系林木的尖削度,与对照相比,H／D值增加了5．1％～9．5％。     

Impact of artificial pruning on growth and secondary shoot development of wild cherry (Prunus avium L.)

Producing high value veneer wood requires that the tree bole be branch-free. This can be accomplished by natural or artificial pruning. Since wild cherry does not self prune well, pruning artificially is the only practical option. The study analysed the effect of conventional whorl-wise pruning and selective pruning, on height growth, diameter growth and secondary shoot development of wild cherry. Four pruning treatments were applied on cherry trees in summer 2007, one group of cherries was left unpruned to serve as a control: treatment C1 (upper 5 whorls left), C2 (upper 3 whorls left), S1 (removal of branches larger than 3 cm or with an angle to the stem < 40°), S2 (removal of branches larger than 2 cm or with an angle to the stem < 40°), N (unpruned). Data showed that height growth was not affected by pruning. In contrast, diameter growth at breast height of the C2 pruned cherry was reduced by approximately 5% (SE = 2.7%) in the year of pruning (trees were pruned in July). This pruning treatment produced significant (p = 0.028) nine percent less diameter growth than the control in the second year following pruning. The diameter increment of the C1 pruned trees with five whorls left after pruning and the selective pruned cherries were only about 4% (SE = 4.0%) smaller than the control after two years. This loss was statistically not significant. Analyses showed that on selective pruned trees the survival rate of secondary shoots was significantly reduced compared to those on whorl-wise pruned trees. Significant differences in the size of the secondary shoots were only found between the C1 and S1 (p < 0.05) pruned trees. We did not find differences in the total number of secondary shoots per tree among pruning treatments. Solely from a tree growth perspective, the moderate whorl-wise pruning treatment C1 and the selective prunings were equally effective in minimizing the reduction of diameter growth and are recommended in practice. However it was found that the survival of secondary shoots was reduced on selective pruned trees although the amount of pruning work needed in selective pruning was slightly greater than conventional moderate pruning.     

Growth of graded sweetgum 3 years after root and shoot pruning

Nursery grown 1–0 bareroot sweetgum seedlings were lifted and graded into two diameter classes (12–16 and 4–8 mm) during the dormant season. Large and small grades were top and/or root pruned and then outplanted on two sites in the lower Coastal Plain of the southeastern United States. Seedling shoots were pruned to 50% of tree height, a 5 cm stump, or no pruning. Seedling roots were pruned to a 15 cm length or left unpruned. Site affected survival but not growth. Smaller, top pruned seedlings performed worse on one site, probably due to greater weed competition. Large seedlings increased survival and growth which increased 3 year average plot volumes by 89%. Top pruning stimulated height growth, but reduced diameter growth and decreased third year seedling volumes. Root pruning did not affect seedling growth. Diameter growth may better indicate treatment impact that height, which has been most commonly used in previous studies.     

Screening of 18 agroforestry species for highly acid and aluminum toxic soils of the humid tropics

A screening trial involving 18 agroforestry species were initiated on highly acidic and Al toxic soils of Nkoemvone, Southern Cameroon, with the objective of identifying fast growing species that can be suitable for improving short fallows. Selected growth parameters evaluated were plant height, stem and crown diameter, number of stems at 3, 12 and 20 months after planting (MAP), and biomass yield at the first pruning (20 MAP). Then 9 months regrowths were evaluated for the same parameters. Outstanding height and stem diameter were observed for Indigofera zollingeriana, Inga edulis, Grewia mollis and Pterocarpus santalinoides. They reached between 6 and 9 m height and between 8 and 10 cm diameter. The best height was correlated to the best stem diameter for I. zollingeriana (8.7, 8.6), I. edulis (7.7, 10.1) and P. santalinoides (6.4, 10.3). The same four species developed a crown of more than 5 m diameter and easily out competed weed in the alley. G. mollis, Glyphea brewis, Dactiladenia barteri and I. zollingeriana had a shrubby architecture; G. mollis had up to 17 stem before the first pruning. Inga edulis and G. mollisproduced the highest total biomass, with respectively 61 and 39 t/ha dry matter. Other species with more than 20 t/ha total mass were I. zollingeriana, P. santalinoides, and Xylia xylocarpa. The first pruning stimulated shoot development, and the response of the species was similar to before the first pruning. Therefore I. edulis, P. santalinoides, G mollis and I. zollingeriana had the best growth performances and can be recommended for introduction in short fallows provided their contribution to soil fertility processes is assessed. This revised version was published online in June 2006 with corrections to the Cover Date.