Pruning & Tree Care

What are the three Ds of pruning?

dead, damaged, diseased

What kind of pruning are used on roses?

Roses bloom terminally on new wood, so the correct pruning cut is a heading cut (just above a bud, essentially removing the spent flower head, to encourage new growth and continued blooming).

count buds from base
3-5 for hybrid tea

CODIT (Compartmentalization of Decay in Trees)

The CODIT process produces Walls I, II, III, and IV barrier zones. The tree uses the four walls to resist the spread of decay or pathogens. The relative strength of each wall increases from I through to IV.

Wall I resists the vertical spread of dysfunction from the wound site. It is naturally weak because the tree needs vascular connectivity for the axial transport of water and nutrients. Surrounding parenchyma cells produce balloon-like Tyloses to fill the vessels and form Wall I to slow the progress of rot and pathogens.

Wall II is the tangential wall inhibiting the movement of decay organisms inward and forming along growth ring cells. Wall II is continuous except where rays pass through.

Wall III is composed of ray cells, which inhibit the movement of decay in a radial direction.

Wall IV is the strongest protective wall formed by the cambium layer and restricts the movement of decay into tissues formed after wounding. The cells are thick-walled and contain chemicals to ward off decay.Wall IV forms new growth, callousing over any wound/disease.

Some tree species compartmentalize better than others. Healthy tree compartmentalization is better than trees in a weakened condition. Vigor gives trees more energy and stored carbohydrates to respond to attacks. Periodic fertilization, pruning out deadwood, watering during dry periods, and controlling insects and diseases improve tree health and are essential in helping trees compartmentalize pathogens and decay.

What deternines the timing of pruning?

If a plant blooms in the summer and fall, it blooms on new wood (current year's wood). Prune in the early spring; you have until late May/June to prune the plant. It is important that you do this, as you only get abundant flowers and fruit on the new wood. If you don't prune, the plant will get leggy and unproductive.

If a plant blooms in the spring (February through June), it blooms on old wood (it set up its buds the previous year). Prune right after blooming; you have a window of 4-6 weeks to prune the plant before the new buds are set for the following season.

What are the steps to prune a tree branch?

cut #1: shallow undercut 4-5” from trunk to relieve compression
cut #2: immediately above undercut, cut branch off to alleviate tension
cut #3: remove branch

What is reaction wood?

In angiosperms, it is referred to as “tension wood”.
In gymnosperms, it is referred to as compression wood.

How does the age of a tree affect form/habit?

Pruning for form is easier on a younger tree. If a tree has been neglected with respect to pruning, it will take a lot of work, over time, to (try) to get it back to looking good,