I presume the land you reference is not homestead property. If this is the case, a probate would need to be opened and the property would flow under Florida's intestecy laws for conveying real property.
You need to probate this estate. It can be done in a summary administration since he died 10 years ago. Your mother receives a percentage share, but not an entire share http://www.flsenate.gov/Laws/Statutes/2011/732.102. You need a lawyer.
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The land will have to go through probate and your mom will need to hire an attorney.
What happens next will depend on if 1st or later marriage and number of children involved.
The answer given does not imply that an attorney-client relationship has been established and your best course of action is to have legal representation in this matter.