Only a few forest tree species can develop viable seed from unpollinated ovules . 只有少数林木可以从未授粉的胚珠发育成有活力的种子。
In the majority of cases their objective is a closed stand with improved yield . 在大多数情况下,他们的目标是使林木郁闭,以提高产量。
The earliest colonists found abundant forests and suitable soil with adequate rainfall . 最初期的殖民者发现美洲林木丰茂,土地肥沃,雨水充足。
It was a warm morning, and the forest scent through the open windows was delightful . 那是一个暖和的早晨,从敞开的车窗外传来的林木气息十分怡人。
Mortality is the number or volume of trees periodically rendered unusable through natural causes . 枯损是一类由于自然原因而定期变得无用的林木株数或材积。
Many forest tree species have multiple archegonia which, after fertilization produce a number of proembryos . 许多林木树种都有颈卵器,受精以后便产生许多原胚。
It is not difficult, however, to arrange our information on forest trees within the framework set by levins . 不过在Levins确定的范围内整理我们关于林木的材料倒不困难。
These conditions should be appreciated when considering estimates of neighborhood size for forest trees given in the literature . 当参考文献中所给的林木邻域大小估计量时,这些情况都应当予以考虑。
High hills rose immediately behind the house and at no great distance on each side, some of which were open downs, the others cultivated and woody . 紧接着房子背后和在两侧不远处,都耸立着高山。有些是空旷的丘陵,另一些则种上了作物或被林木所覆盖。
Analysis on forest resources and forest resources assets 林木资源资产收益权评估