What percentage of Earth's land is covered by trees?
601098
Don't know, but I can tell you that the number continually drops.....
160700
It's not the money!\nIt's the fact that the earth will be terribly out of balance and mother nature will take a drastic nose dive if there are not more forests.  All life will probably die.\nOur atmosphere is created by all the plants and trees giving off all their oxygen.  Earth would not be the beautiful life supporting place that it is without trees.
494215
If by "tillable" you mean "arable": i.e., land that can be used for growing crops, then about 12 million square miles (31,000,000 km²). That's about 21% of the planet's land area.
458236
Just the Jungles.\nNo land is free in this world.\nThanks to USA.
599140
Igneous rocks make up approximately ninety five percent of the upper part of the Earth's crust, but their great abundance is hidden on the Earth's surface by a relatively thin but widespread layer of sedimentary and metamorphic rocks.
550018
There are many.  What follows are just a few, and I am certain many people would put them into different catagories:\n\nDeforestation is one.  Humans have cut down many areas of natural vegetation and either replaced it with crops or built cities on it.  Plants return oxygen to the atmosphere from carbon dioxide; they reflect light and adsorb heat from the sun.  Both plants and the soil help adsorb water and pollutants.  The more of the planet we pave, the fewer trees and less soil exist to regulate these functions.\n\nPollution is another.  We dump our trash on land and in the oceans.  We create chemical compounds that wouldn't exist in nature and spread them in the land, water, soil and air.  Some directly effect the health of living things; others effect things like the ozone layer, taking away natural system that protect life on this planet.  We dump the heat from our indutrial processes into the atmosphere and water.\n\nAnd, now, we're relatively certain we are creating enough waste of carbon dioxide, water vapor, and other gases in our atmosphere to trap excess heat in the atmosphere.  Enough of it to warm the entire globe just fast enough that plants cannot adapt.  Fertile zones will change.  Crops may fail.  Livestock (and wild animals) that depend on plants for forage may die.  Areas that we now comfortably inhabit - with suitable climates and drinking water may become desert.  Others may end up under rising oceans as glaciers melt.\n\nWhat can we do about it?  Everyone will likely have a different answer.  As an American, I have to say I am more guilty than many others who will read this.  The average American family (about 5 people) owns 9 internal combustion (gasoline or diesel) engines; in a still developing nation like China, there is one engine for every 159 people. If the Chinese lived like the American, how much soot, smog, waste heat, and carbon dioxide would be produced on a single summer day of driving, lawn mowing, and boating?  How much could our planet take?\n\nThe answers aren't easy.  In the short term, we can use applicance - from light bulbs to computers - that are more efficient in how they use the energy we make.  We can think about how to reuse things to create less waste; or not use them at all. (Seriously, how much of your groceries really need to be double bagged?  And does your produce really need to go in another bag inside that?) We can decide whether we really need to build a new 3 bedroom house for ourselves, or if an older, smaller place can be refurbished to suit our tastes. \n\nBut, ultimately, we use too much.  We burn too many things to create the energy we use.  Period.  But, what are the alternatives?  Deforest vast tracts of land to crate wind and solar farms?  I will leave you to draw your own conclusions, but it seems more and more like the future of our existence on Earth depends on the right answer.
222115
more land with no trees.
1078802
Trees absorb CO2, and animals emit O, but there are so many trees being "Slash" cut so that "They" can give me tons\nof advertisements in my Sunday Newspaper, we now are short of O in the air, but plenty of CO2 in the air. This causes "Global Heating". "They" had better stop destroying our forests or there will be an end to\nlife on earth. Nitrogen? Probably from the same source as\nin the tree sequences.
521085
Not enough.  In the past 10 years we have cut down 64 million more trees than we have planted.  We should all be planting a tree!
325978
About 3% of earth's water is fresh water with two-thirds of this locked in glaciers and polar icecaps. So only 1% is in lakes and rivers.
646483
Earth - 100%\nMoon - 16.6%\nMercury - 37.8% \nVenus - 90.7%\nMars - 37.7%\nJupiter - 236.4%\nSaturn - 106.4%\nUranus - 88.9%\nNeptune - 112.5%\nPluto - 6.7%
255638
Most territory that's not covered by a city would be Alaska.  Interesting, Nevada looks to have the highest percentage of non-improved land.
118359
That is a good question.  Trees are a renewable resource though, so it is kind of a non-issue.
83487
Yepp...all countries that heavily chopped off their trees lend a helping hand to soil erosion and thus, land slides. It is quite common in India.
1087611
More than 70% .        Of the whole earth's surface 80% is water. \nIt's too bad, 97.2% of all the water on earth is salt water though. \nNow, where do you think most salt water is found? That only leaves 2.8% is fresh water that we can drink or play in.
828711
The better question is what percentage of land is desert, in which case it's something on the order of 4-9%.  Roughly.
518898
There live about 6 billion people on the Earth, so it's about 1/6 of the worlds population. Don't know how much % that is... sorry...