"tomba wrote:
I am not sure this is the best place to ask this question. There were
two large trees in my backyard which provided a lot of shade. I had to
have them removed, and I thought that my house would be much hotter at
night. I do not use AC. With the trees removed it seems as if the
house is cooler. The only two reasons I can come up with is that the
trees blocked evening breezes, or that the trees absorbed heat during
the day, and gave it off at night which made my house hotter at night.
Would this make sense?

Too many details missing but in general the same trees that shade a
house during the day increase humidity inside a house, which make it
feel warmer at night. Tree limbs should never be permited to hang
over a roof, the constant shade causes moisture accumulation in
roofing materials, which can cause severe damage to roofing materials
and roof sheathing. Also the heat that builds inside an attic during
daytime radiates into the house by inversion as soon as the outside
air cools at night. Have you logged indoor temperature and humidity
levels? Trees cannot take the place of good insulation, light
blocking window blinds, and air conditioning. Attic ventilation and
radiant barriers can help somewhat but they do not eliminate radiant
heat inversion. Trees however do offer substantial cooling, if you're
a bird.

http://www.ornl.gov/sci/roofs+walls/radiant/index.html