How to Prune an Alder

Remove any dead branches or debris from around the tree before you begin pruning. Remove any excess debris from around the base of the tree in between pruning, as well, to reduce the risk of root rot or the spread of other diseases throughout the year.

Assess the overall tree shape and scan for any branches that are poised toward houses, telephone lines or any other structures. Focus your pruning on these branches. Slice cleanly through the branches you wish to remove, cutting them where they join to larger branches. Avoid leaving any stubs, which may attract disease.

Identify the leader branch, the dominant stalk that rises straight upward from the top of the tree. If you find the tree has two leaders, cut off the one that appears smaller and weaker. Cut the branch directly above the point where a smaller branch forks off it. Make your cut at about 45 degrees, cutting downward on the side away from the smaller branch.

Hire a professional tree service company to do any required pruning on upper branches that you cannot reach yourself. Focus your attention on deadwood if you're pruning an older tree, thinning out the branches to leave the healthiest shoots. Also remove any "suckers," the odd new growth that occasionally emerges from tree trunks and larger branches.

Repeat your pruning practice every winter, reducing the frequency and intensity of the pruning as your alder ages. Wait until November or December, after the summer growth has ended, to do any general pruning.