. Cyclopedia of farm crops : a popular survey of crops and crop-making methods in the United States and Canada. Agriculture -- Canada; Agriculture -- United States; Farm produce -- Canada; Farm produce -- United States. 14 THE TLAXT: ITS STRUCTURE, LIFE-PROCESSES AND EXVIROXMENT The storaata are usually closed at r\\ght; hence it is then jKv^ible to fumigate plants with poisonous prases that would kill them if applied through the day. Closing at night prevents the stomata clog-. Fig. 32. Diagram of a stoma or stomate (of Iris) in section, ing guard-ceUs and neighboring ceUs of epidermis. ging
. Cyclopedia of farm crops : a popular survey of crops and crop-making methods in the United States and Canada. Agriculture -- Canada; Agriculture -- United States; Farm produce -- Canada; Farm produce -- United States. 14 THE TLAXT: ITS STRUCTURE, LIFE-PROCESSES AND EXVIROXMENT The storaata are usually closed at r\\ght; hence it is then jKv^ible to fumigate plants with poisonous prases that would kill them if applied through the day. Closing at night prevents the stomata clog-. Fig. 32. Diagram of a stoma or stomate (of Iris) in section, ing guard-ceUs and neighboring ceUs of epidermis. ging with dew. Water-proof materials, as well as hairy coverings of the leaf, protect the stomata from dew and rain. Leaves so protected appear silvery under water and do not become wet for a long time. If such protection is found on the lower side only, the stomata will be found on that side only. House plants should have the leaves washed occasionally to prevent the clogging of the stomata with dust. The devices by which desert plants check evaporation will be discussed later. The carbon dioxid, passing through the stomata, comes directly into contact with the leaf-cells, which are sufficiently separated from each other to allow it to pass freely between them (Figs. 33, 34). The great absorptive surface which they expose is kept continually moist and is thus able to absorb with great rapidity, much as the moist lung sur- faces absorb oxygen. The absorbed carbon dioxid into the cells and comes into contact with the green chlorophyll grains. The chlorophyll (leaf- green) in these bodies is divided into very minute drops (Fig. 35), thus giving it an enormous ab- sorptive surface. At the same time that it takes up carbon dioxid it absorbs sunlight, and with the energy thus received decomposes the carbon dioxid ^ Fig. 33. Cross-section of ivy leaf, which grew in shade, and has only one layer of palisade-cells, w, upper epidermis; p. palisade rells: c, a crystal: sp. spongy pare
Size: 2016px × 1239px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookidcyclopediaoffarm00bailuoftbookyear1922
