NO! This is not an acceptable practice. Topping causes a lot of issues including stressing the tree, decay, sunburn, and unacceptable risks. Topping also leads to more expense such as maintenance, reduced property value and increased liability.
Yes!
A good rule of thumb is no more than 2 inches thick and to have the mulch ring go out to the drip-edge of the tree.
Early Spring is the best time to plant a tree to give it the best chance of establishing itself. This gives it time to add new growth and start the process of getting proper nutrients from the soil in its new home.
Any time after flowering. If pruning is done before flowering, you will be removing flower buds therefore eliminating the flowering.
No. Proper cabling and bracing will not harm the tree in any way. It should actually prolong the life of the tree. Cabling comes in two forms, static (steel) and dynamic (rope). Depending on the tree and the reason for cabling will determine the type of cable and/or bracing needed.