for the majority of tree species this method appears to be very well suited . 對于大多數(shù)樹種來說,這個方法看來都是適合的。
only a few forest tree species can develop viable seed from unpollinated ovules . 只有少數(shù)林木可以從未授粉的胚珠發(fā)育成有活力的種子。
many forest tree species have multiple archegonia which, after fertilization produce a number of proembryos . 許多林木樹種都有頸卵器,受精以后便產(chǎn)生許多原胚。
where forests are concerned, the difficulty is increased by the longevity and competitive capacity of dominant tree species . 只要哪里涉及森林,就由于優(yōu)勢樹種的長命和競爭力而增加困難。
a study on landscape tree species planning in kunming 昆明市園林樹種規(guī)劃研究