[colin79ie]

I would like to plant a nice tree at the side lawn at our house. The space is not big so something that is either slow growing or doesn't grow too big.

My wife likes the cherry blossom and I think I seen a weeping cherry blossom in Aldi today? Anyhting that would be colourful would be nice.

One concern I have is that the house sewerage pipe runs under this lawn and I would like to know if there is any possibility that the sewerage pipe could get damaged through time by a tree's roots. I have no knowledge of trees or roots or anything. I am a beginner gardner.

[Liparis]

As a general rule, a tree's roots equal the span of it's branches. So, you need to choose a tree with that in mind and plant it an appropriate distance from what you don't want damaged by them, erring on the side of generosity.
You could go for flowering cherry or ornamental crabs, flowers, then fruit for the wildlife later with the crabs, plus they can be as floriferous as the cherries. So whatever you choose, give it lots of room from your sewerage pipes. If your stuck for space to do that then go for the more shrubby types of cherries, or even just shrubs.
Bill.

[cooler]

A compromise maybe, half shrub, half tree. Amelanchier grows well here in Ireland on neutral or acid soils (no lime). White flowers in March and April and green leaves that turn orange and red in autumn. Dark purple berries sometimes appear in summer. Here is a pic