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Manner Of Growth: Lateral growth in trees frequently begins later than growth in height, but the period of lateral growth is longer. Rates of lateral growth likewise are low at the outset, increasing after a few weeks and then diminishing. In view of the long annual period of lateral growth in trees, deleterious environmental conditions may exercise a pronounced effect on growth. In the wood of trees of temperate regions, narrow and wide growth rings may be observed, marking years characterized by unfavorable and favorable conditions for growth.
Grasses occur in a wide range of sizes. Annual bluegrass (Poa annua) may reach only about two inches in height at maturity and flower only a few weeks after germination of the seed. Some bamboos of tropical America and Asia produce extensive forests, have stems (culms) as tall as 100 feet (30 meters), and produce flowers only after 60 or more years of growth. In spite of such great differences in manner of growth, size, and life-span, both annual bluegrass and bamboo have features in common that indicate a close relationship and mark them as members of the grass family.
Adults of dragonflies and damselflies cannot be maintained in captivity but the nymphs can, especially those of the giant dragonfly. When properly maintained they will develop normally, reach full growth, crawl from the water, and demonstrate the manner in which the adult emerges. |
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