Question: who found gravity?

Werner Muller answered on 11 Nov 2013:

People think that newton found gravity by watching an apple falling down from an apple tree. On this web page (http://www.semanto.me/apple-incident/) for example you find a picture of the famous apple tree . The apple tree is so famous that even the University of Manchester as a smaller version of the same apple tree in one of his gardens. The tree is close to the Sackville street building. It is a challenge to find the tree (specially in winter). The small plaque next to the Manchester apple tree says that there are three trees but I could only find one. May be something to follow up in case you make it to Manchester University some day. Where are the other two Newton Apple trees in Manchester?