"Land" in this context is defined broadly. Note the following legal definition of "land."

LAND - This term comprehends any found, soil or earth whatsoever, as meadows, pastures, woods, waters, marshes, furze and heath. It has an indefinite extent upwards as well as downwards; therefore land, legally includes all houses and other buildings standing or built on it; and whatever is in a direct line between the surface and the centre of the earth, such as mines of metals and fossils. In a more confined sense, the word land is said to denote "frank tenement at the least." In this sense then, leaseholds cannot be said to be included under the word lands.

The technical sense of the word land is farther explained by: "if one be seised of some lands in fee, and possessed of other lands for years, all in one parish, and he grant all his lands in that parish (without naming them) in fee simple or for life; by this grant shall pass no, more but the lands he hath in fee simple." It is also said that land in its legal acceptation means arable land.

Land, as above observed, includes in general all the buildings erected upon it, but to this general rule there are some exceptions. It is true that if a stranger voluntarily erect buildings on another's land, they will belong to the owner of the land and will become a part of it; yet cases are not wanting where it has been decided that such an erection, under peculiar circumstances, would be considered as personal property.
http://www.lectlaw.com/def/l063.htm