Wherever you live, and whether you are looking for a single tree to fit in a corner of a small back garden or dozens to plant in a field or the grounds of a public building, native species are usually the best. This does not mean that you should never plant exotic species (which means trees from outside the UK), but if you are planting on a large scale the majority of trees should be native species.
Why native species? Simply because these have evolved to be best suited to local conditions and provide a home for the largest number of types of insects, birds and other wildlife. Here in the UK there are roughly 35 native species, although several of these don’t grow wild in the Manchester area, such as the Scots pine (Highland Scotland only) and the hornbeam (Southern England only). This makes the list of species to choose from relatively short.
Hawthorn leaves and berries in October. The hawthorn is a small native tree suitable for relatively compact gardens. 
Apple tree in flower surrounded by a crop of wild garlic, also known as ramsons. This tree is also suitable for small spaces.
Your choice is in fact easier because a few native species have unfortunately been wiped out by disease over large parts of the country (elms) or are threatened by the same fate (common ash). We can’t recommend planting these because elms will be killed by Dutch elm disease before they are full-grown, and ash trees will run the risk of being infected by ash dieback fungus. Other species (poplars and the taller species of willow) often lose large branches and thus can’t be planted where people are likely to walk beneath them.
Depending on the amount of land you have available, we have put together two lists of native species. One of these contains small native species suitable for average back gardens, whereas the other includes larger native species that might outgrow a back garden but are suitable for an open space in a park or school grounds. All of these should provide homes for various types of birds and/or pollinating insects.
