A house, car, or equipment suffer from wear and tear over time, making them worth less and less. Land does not do this. You can, of course, ruin the value of a property by tearing it up, dumping chemicals, or any number of things... But if does not "wear out". Other than fluctuations based in real-estate values rising and falling... The land generally retains it's value or increases in value (unless you spent too much on it to begin with). In fact, over the long term, land is the best investment, IMO, because unlike things which are depreciated, land will go UP in value over the long term, because the demand is always increasing, while they are not making any new land.
Land in general do not depreciate as demand increases with population increase. It can also go down in value for a host of reasons, mostly due to political and environmental changes. For example, new restrictions on what you can use the land for (zoning), tax rate changes, a proposed noisy highway, a new coal-fire station next door, polluted water, drought, proposed prison...will make the property less desirable, thus less valuable.
There's an article at the link below that talks about depreciation on real estate in general. As far as depreciating for your tax return the value doesn't really have much to do with it other than in figuring out how much of your initial total purchase price went to land vs. Building(s). As the first answerer said, land can't be depreciated because it doesn't wear out. It was there before the present house (or other building) and it'll be there long after.
If you're doing your taxes you should note that you CAN depreciate some things you might think of as "land", like the driveway, some landscaping, etc. For some simple articles on real estate depreciation see http://easyrentaltools.com/tutorials/depreciation-basics.cfm
The value of any asset diminishes with its usage due to the deterioration, wear and tear. This is not the case with land. Its usage does not lead to its wear and tear. A vehicle is a tangible fixed asset and is subject to wear and tear. Its value declines with passage of time and its usage. Practically, no one would buy second hand motor car at its original price. Neither, any land would be sold at the price lower than its purchase price after few years of usage.
The depreciation leads to such state of asset whereby the book value is almost nil. This is its scrap value and normally restricted to 5% of the original cost.
Depreciation annually computed on straight line basis is arrived by :-
(Original Cost – Scrap Value expected)/Life of the asset in years
Do we ever hear about land arriving at the scrap value due to its usage?
In-fact value of the Land always appreciates and does not depreciate.
Building standing above the land depreciates but not the land.
