论文部分内容阅读
楸树是我国北方珍贵的速生用材树种。近年来我们发现楸树和灰楸(本文一并讨论)存在许多自然类型。这些类型在形态、生长、材质及适应性等方面均有明显差异。所以,从中选择出速生、优质的自然类型,对发展揪树将具有一定的意义。一、自然类型的划分根据我们在豫西的普查,初步将楸树划分为金丝楸、心叶楸、长果楸、槐皮楸、光叶楸、长柄楸、密枝楸及三裂楸等八个自然类型;灰楸划分为密毛灰楸、细皮灰楸及窄叶灰楸三个类型。现将各类型的主要区别列检索表如下:1.小枝、花序及叶密被分枝的毛:叶基腺体多为3个以上…………………………灰楸(Catalpa fargesii Bur.)2.叶片狭长,长宽比2:1,广披针形,基部楔形………………………………………………………………窄叶灰楸2.叶片长宽相近,心形。3.树皮暗灰色,深纵裂;小枝、花序及叶密被灰白色的分枝的毛:叶基部脉腋间常具3-5个紫黑色的腺点………………………………………密毛灰楸3.树皮灰白色,细长片状翘裂,小枝及叶片分枝的毛较短而疏,叶基脉腋间有2-4个绿褐色腺点…
Catalpa bungei is a precious species of fast-growing timber species in northern China. In recent years we have found that there are many natural types of Catalpa bracteos and Catalpa bungei (discussed in this paper). These types have obvious differences in morphology, growth, material and adaptability. Therefore, choosing a natural type of fast-growing and good quality will have some significance for the development of the tree. First, the natural type of division According to our census in western Henan, Catalpa bungei will be initially divided into two kinds of: Catalpa bungei, Cercis chinensis, Prunella vulgaris, Kojicopsis ciliata, Catalpa bungei, Catalpa bungei and other eight natural types; Cuscuta sorbifolia is divided into three types of dense hairy Catalpa bungei, Catalpa bungei and narrow-leaf Catalpa bungei. Now the main types of different types of columns to retrieve the table are as follows: 1. Branchlets, inflorescences and leaves densely branched hair: leafy glands are more than 3 .............................. Catalpa (Catalpa fargesii Bur.) 2. Blade narrow, 2: 1 aspect ratio, broadly lanceolate, base cuneate. 2. Blade length and width similar to heart-shaped. 3. Bark dark gray, deep longitudinal split; branchlets, inflorescences and leaves densely gray branches of hair: leaf base veins axillary often 3-5 purple black gland ........................... .................. Mighty Sorrel 3. Bark gray-white, slender sheet cracking, twigs and branches of the hair shorter and sparse, leaf axillary axillary 2-4 green brown gland point ...