I have two birches growing in front of the house next to each other. They were put in two years ago but problem is one of them is really bending over at the top so bad that the tip is now pointing downwards. Wondering if anyone would have any clues why this would be and solutions (if any). Other one is fine and in similar soil. Both have healthy strong growth and plenty of leaves...Any clues?? It's not a weeping type either for your info....

Garry