| quote | Narrow, cylindrical coniferous needles have been shown to be the most effective 'collectors' of airborne fog particles and, perhaps, water vapor as well (Ettenheim 1962). This needle form is typical of the coast redwoods, which survive in an area of only about 35 in. of annual precipitation, a surprisingly low figure considering the apparent water demands of these giant trees. Eucalyptus, cedars, and other conifers also have a leaf shape that is effective in collecting water from the air (Oberlander 1956), and they thrive in the same type of climate. Other types of vegetation are generally less effective in collecting droplets or vapor. |