Search results
Results from the WOW.Com Content Network
Aspen trees are all native to cold regions with cool summers, in the north of the northern hemisphere, extending south at high-altitude areas such as mountains or high plains. They are all medium-sized deciduous trees reaching 15–30 m (50–100 ft) tall. In North America, the aspen is referred to as quaking aspen or trembling aspen because ...
A wild fig tree growing in Echo Caves near Ohrigstad, South Africa has roots going 120 m (400 ft) deep, giving it the deepest roots known of any tree. [115] El Drago Milenario , a tree of species Dracaena draco on Tenerife, Canary Islands , Spain , is reported to have 200-meter-long (660 ft) superficial roots.
Two main opposing forces affect a tree's height; one pushes it upward while the other holds it down. By analyzing the interplay between these forces in coast redwoods (Sequoia sempervirens), a team of biologists led by George Koch of Northern Arizona University calculated the theoretical maximum tree height or the point at which opposing forces balance out and a tree stops growing.
Evergreen trees also lose leaves, but each tree loses its leaves gradually and not all at once. Most tropical rainforest plants are considered to be evergreens, replacing their leaves gradually throughout the year as the leaves age and fall, whereas species growing in seasonally arid climates may be either evergreen or deciduous.
The shape of the tree is an adaptation for survival in arid conditions with low amounts of soil, such as in mountaintops. The large, packed crown provides shade and reduces evaporation. This shade also aids in the survival of seedlings growing beneath the adult tree, explaining why the trees tend to grow closer together. [1]
A spruce is a tree of the genus Picea (/ p aɪ ˈ s iː. ə / py-SEE-ə), [1] a genus of about 40 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal regions of the Earth. Picea is the sole genus in the subfamily Piceoideae.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
Christmas tree cultivation is an agricultural, forestry, and horticultural occupation which involves growing pine, spruce, and fir trees specifically for use as Christmas trees. The first Christmas tree farm was established in 1901, but most consumers continued to obtain their trees from forests until the 1930s and 1940s.