Looks like Taxodium distichum. Common name Swamp cypress. http://images.google.com/images?q=T...1I7SUNA_en-GB&um=1&ie=UTF-8&sa=N&hl=en&tab=wi http://www.conifers.org/cu/tax/distichum.html
Over here the prevalent common name is bald cypress. Jacobson, North American Landscape Trees (1996, Ten Speed, Berkeley) lists Bald cypress Common bald cypress Deciduous cypress Louisiana cypress Southern cypress Swamp cypress Marsh cypress Gulf cypress Sabino tree in that order.
Swamp Cypress make some sence when you look at the one on the hill with less water is not fairing as well as the three in the lower ground where there is more moisture.
Of course Bald Cypress also makes sense, they'll be 'bald' (leafless) very shortly, unlike other cypresses which are all evergreen
