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Cactus Flowers (Postcard Books)
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by Jeff Nicholas
Sales Rank: 1203758
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$36.69
At Amazon
on 12-27-2008
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Stationery: 15 pages
Publisher: Sierra Press; 1 edition October 1994
Language: English
ISBN-10: 0939365391
ISBN-13: 978-0939365395
Product Dimensions:
0.2 x 5 x 7.2 inches
Shipping Weight: 4 ounces
Product Description
Each year there is anticipation of spring in the desert, and the spiny stems of cacti provide quite an unusual host to some of the desert's most brilliant colors. In the United States, the cacti reach their highest diversity in the deserts with Texas and Arizona having the greatest number of species, followed by New Mexico and California. They can be found naturally in all of the contiguous United States except Vermont, New Hampshire, and Maine. While all cacti are succulent, not all succulent plants are cacti. Other characteristics, in addition to succulent stems, that group cacti together include flowers with many petals and stamens, and an inferior ovary that produces a many-seeded fruit. Cacti are stem succulents that are mostly leafless. There is one genera of tropical cactus (Pereskia) that actually has persistent leaves, and one common desert genera (Opuntia, or the prickly pears and chollas) that produce ephemeral leaves on young stems that are quickly shed. Cacti are masters at desert survival and minimizing water loss. Cacti have an efficient strategy for reducing water loss. Instead of opening their stomata (pores on the stems) during the day to exchange oxygen for carbon dioxide (CO2), they open at night when the humidity is higher and temperatures are lower. Since photosynthesis, or the process of converting (CO2)into sugars, can only occur in sunlight, the cacti store the (CO2)as organic acids that release the (CO2) during the daytime. Cactus also save water by having a waxy coating on the stems, and a low ratio of surface to volume (more volume to save water and less surface area to loose it from). Overall there are over 90 genera of cacti and about 2,000 species found in the western hemisphere from Canada to southern South America. While cacti are primarily desert plants, they can also be found in tropical rain forests, in relatively moist areas east of the Mississippi River, and in places where the water table is only inches below the surface soil.
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Cactus Flowers (Postcard Books)
Available from Amazon
Price: $36.69
Updated on 12-27-2008
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