Which Trees ?

Hello Bill, poplars and willow are fast growers, but carefull thought would be needed because you dont want these too close to your house because of the root systems, so how big is your garden and would whatever you plant be a problem for neighbours?, the obvious choice would be leyladii, aprox 3ft growth a year, you could go for a Birchtree which will give you dappled shade, white bark, lovely butter lemon leaves in the autumn, or how about Amalanchier, great autumn colour, but not as fast as the above trees mentioned, julien.

When i was doing my research for a new tree, i decided on Betula Utilis Jaquemontii 'Silver Shadow' (birch) which we planted last autumn, on the Crocus website it tells you how fast plants grow in the description which is always helpful

Fast growing trees do not stop growing when they get to the height you want them... they keep right on growing!

Willows and poplars get far bigger than 40 feet - they wouldn't be a good choice at all. Leylandii get enormous! don't plant that.
How about a cherry? Different varieties grow to different sizes, but can be fair sized trees.

Thanks everyone ! My garden is nearly 100ft and i want them at the back to try and cut out some of the wind made worse by aircraft engines when they take off over my house. The previous owners cut down around 10 trees for some strange reason as my neighbours said they were cherry. It wont shade my garden at all but i suppose id better think of the neighbours at the back because it would shade their garden.. i will look up the ones you have all kindly posted on here thank you very much !