why does defolliating a tree slow down its growth?
608779
No leaves = no photosynthesis.  No photosynthesis, no growth.
51996
I thought that plants didnt really grow towards the sun, its more that the growth is slowed in the cells due to the presence of excess plant hormone Auxin which is produced in sunlight causing them to grow faster on the "dark"side resulting in the appearence of them "growing" towards the sun (phototropism)
975859
when a tree is chosen to develop as a bonsai, the tap root is cut off and the finer roots shortened. As the tree developes more roots they become finer as they are trimmed and fill the container. This process is continued throughout the life of the tree so they don't become root bound. On the topside of the tree, the leaves are trimmed off and they come back smaller each time. The branches are also trimmed to maintain the shape of the tree and height.
1128795
That depends entirely on the species of tree, where it is growing and what you want to use it for.\n\nMany tropical and subtropical hardwoods such as Pinus radiata are capable of growing to usable size within 10 years. Other species may take as much as 100 years.
376956
it is not the sharpness of thr needles. fred is right that the needles themselves make the soil acidic as they break down on the soil surface and release tannins and their resins, this stops anything growing underneath in a pine forest. however, if you are removing all the fallen needles, there is another thing ... if you dig even a little under your tree you will find that the ground is full of roots AND the associated root fungus that pines have (this is good fungus and looks like white mold around the roots). this tends to make it hard for grass to establish, also.
319622
it happens when the water says down in the roots in the fall.... water is the food for the leaves.... easier to say then that it's loss of chlorophyll
1061226
Try defraging your computer: Start button- Programs- Accessories- System tools - Disk defragmenter. \n\nYou files may be broken up all over your hard drive and it has to look over your whole hard drive to find the last files, that is what may be causing the slowdown, or you have things running in the background of windows that suddenly needed memory causing it slow down. Press ctrl+ alt + delete and if you have XP you will see a tab on the task manager for performance, have a look at that next time you burn, see if anything spikes.
129103
Moisture content of the leaves, ambient temperature of the leaves both affect the pace of decomposition.  Also, leaves tend to decompose faster anaerobically (without a large supply of fresh air), so leave deep within a large pile will decompose faster than those on the outside of the pile.
192873
Dont listen to teh idiot above, how could cutting down trees help improve the ozone layer???\n\nThe answer is A because trees convert CO2 to O2, the more trees you cut down the less trees you have to make 02 from CO2 so there will be an increase in CO2
534921
For the population density of say, a large sauropod, which were chiefly herbivorous, they would have had to consume extreme amounts of high energy foods to grow fast.  Since plants require a massive metabolism to digest, their metabolism must have been very slow, which in turn means that they grew slowly.  \n\nA carnivore like your garden variety t-rex, which was also very large, would have had a faster metabolism because he ate (supposedly) large quantities of protein, but still, every organism´s metabolism is dictated by the same rules, so t-rexes must have been slow too, thus indicating that they also grew up pretty slow (considering their size of course).
577463
Many chemical reactions proceed slower at lower temperatures.  These include those related to spoilage of food eg ripening of fruits, and breakdown of meats.\n\nThe chemical reactions of living cells will slow, too.  This decreases the rate of multiplication of fungi and bacteria, that would contribute otherwise to food spoilage.\n\nBasically, by slowing down the movement of atoms, the rate at which they collide and join or break is also reduced.\n\nSome bacteria grow OK at low temperatures eg Listeria monocytogenes, and even Pseudomonas aerginosa ca grow a bit in refrigerators.  So cold does not completely stop all bacteria.  It is useful to slow them down.
642859
The tree uses different systems or parts of the body for adaptation of a certain environment. \n\nFor example. The tree which grows in a desert condition will have less leaves and thick leaves (Adaptation to preserve water and minimize evaporation) Roots will be tug deep to find water. \n\nAir affects the trees if there is too much of wind blowing in that cases trees tend to be deep rooted and less broad to with stand the winds. (example coconut trees in sea side)
1178216
The pulp of this fast growing trees is use for making high quality paper.The demand for paper is growing and demand is falling short.Henceforth you have a planting and deforesting programme to sustain the paper industry
789781
they are dead.\n\njust like dead tree limbs, they fall off in time.\nit's called gravity.\n\nthe tree goes dormant, the leaves are not needed any longer for this year.\n\nthe leaves are dead and gravity will pull them to the ground
15201
The leaves on any tree/plant work mainly as the energy center to enhance the food supply of the plant.  Photosynthesis is the primary action within the leaves, not the storage of water.  The roots, and the trunk of the tree maintain the water.\n\nSo when a tree looses it's leaves it simply maintains it's primary surface, ie trunk and branches, by storing the water within the lower roots, and within the innermost section of the trunk.
554851
None.It grows that way.On trees of course.lol
729758
Well, I suppose if every tree in the world were chopped down and no more were allowed to grow, deforestation would stop.  I hope you get some serious answers but I don't think there is an answer.  Its been happening since the dawn of civilization.  Some areas in Central America have been deforested several times over.  Its a repeating cycle.  Area attracts people, population increases, trees cut down, ecosystem changes, civilization there declines, people leave, forests return.