What times of the year is it best to prune the following plants and why?
a) Apricot
Apricots are long lived, large trees with a moderately spreading habit. They can be susceptible to diseases such as gummosis and bacterial canker and excellent 
hygiene is necessary when pruning.
hygiene is necessary when pruning.
Formative pruning is used to create a vase shaped tree with three or four main limbs dividing into two secondary limbs. Laterals will grow from these limbs and fruiting spurs develop on two year and older wood. Flowers are produced on both one year old wood and, as the tree matures, on spurs which arise from older wood. Apricot spurs are not long lived, but will bear for 2 or 3 years.
Prune immediately after harvest provided the weather is fine and warm. Reduce upright growths to a welldirected lateral and remove old, crowded or weak spurs. This will encourage the formation of new spurs. Severely cut back or remove laterals from the centre of the tree to promote good air circulation.
b) Apple
Pruning of apples and pears is traditionally carried out during winter while the trees are dormant. Any pruning should always include the removal of dead, damaged or diseased wood and the removal of any suckers which have grown up from below the graft.
Apples
Apples are a medium sized deciduous tree which will grow to 10 or 15 metres if left unpruned. Either dwarfing rootstock or regular pruning is used to restrict apples to a more manageable size.
As with all fruit tree pruning it is important to know where the next years fruit will occur so that fruiting wood is not inadvertently pruned off. Apples fruit mainly on short permanent spurs arising from wood older than two years. Some varieties such as Jonathon and Golden Delicious will also produce smaller quantities of fruit on the ends of the previous seasons growth.
Young apple trees can be trained either to a vase shape or a pyramid shape. Whichever shape you chose aim to produce four or five main limbs with a couple of secondary limbs arising from each. Once this framework is in place annual pruning is directed to the development of fruiting spurs arising either directly from the main branches or from well placed laterals.
Remove any inward growing branches, any crossing or rubbing branches and any overly vigorous vertical growth. Leaders should be cut back to control the overall height of the tree. Pruning to an existing well placed lateral is preferable to pruning to a bud as it will result in less rampant vertical growth the following season.
Laterals arising directly from the main branches should be pruned back by half to two thirds to encourage them to develop fruiting spurs. Prune to a downward facing bud to produce more horizontal growth and encourage the earlier formation of fruiting spurs.
Any inappropriately placed or crowded laterals can be removed entirely. For those varieties which also fruit on the previous seasons lateral growth, the laterals should be thinned rather than pruned back.
Once developed, fruiting spurs may need thinning to ensure the fruit has adequate room to develop without over-crowding.
c) Peach
Formative pruning is directed to creating an open vase shape which allows good air circulation to reduce future fungal problems. A framework of 4 – 6 branches is developed from which the fruiting laterals grow.
Peaches and nectarines require heavier annual pruning than other stone fruit as they bear solely on the previous season’s growth. Once a lateral has borne fruit it will never fruit again. Each year, old growth needs to be replaced with new growth to prevent branches becoming long, willowy, and productive only at their tips.
Pruning consists of removing all laterals that have fruited, either completely, or to a new lateral shoot or bud near their base. Current season’s lateral growth may need to be thinned to allow sun and air into the canopy. New growth should be pruned in early to mid summer and the remaining pruning completed immediately after harvest.
d) Roses
Roses can be pruned twice per year. Summer is mainly for dead-heading and in Winter roses can be given a much harder prune to encourage good, solid, new growth. In Winter its done when the danger of frost has passed, so the new shoots are not damaged.
What is Formative pruning?
references:
http://www.cogs.asn.au/tips-and-techniques/pruning-pomes/
http://www.abc.net.au/gardening/stories/s2288062.htm
http://aces.nmsu.edu/pubs/_h/h-156/welcome.html
-----------------------------------------------------------------------------------------
Question 7
Describe what is meant by the 3 cut process when removing a tree limb.
1. Make a small wedge shaped cut on the underside of the branch just on the branch side of the stem collar. This will break the bark at that point and prevent a tear from running along the bark and stem tissue.2. Somewhat farther along the branch, starting at the top of the branch, cut all the way through the branch leaving a stub end.3. Finally, make a third cut parallel to and just on the branch side of the of the stem collar to reduce the length of the stub as much as possible.
References: http://tree-pruning.com/how-to-prune.html
---------------------------------------------------------------------------------------
Question 8
Should you treat a large tree wound with a sealant?
No: Trees have their own mechanisms for closing an injury. During its life span, a tree will suffer many millions of injuries, some as tiny as an insect bite and others as large as a split trunk. A tree protects wounds from invasion by "walling-off" (compartmentalizing) an injury. According to U. S. Forest Service research, pruning sealants can actually harm trees by slowing wound closure. For rapid healing, use proper pruning techniques and periodically clean your pruning blades with alcohol to avoid spreading disease.
reference:http://aces.nmsu.edu/pubs/_h/h-156/welcome.html
-----------------------------------------------------------------------------------------------------------------------------------------
Question 10
What is meant by the term apical dominance in plants?
and
Question 11
Removing the apical bud in plants encourages what type of growth response?
Removing apical dominance makes a plant bushier.
-----------------------------------------------------------------------------------------------------------------
Question 15
In a fruit tree such as an apple, what is a flowering spur and how can it be recognised?
Tree fruit have two types of buds, terminal and lateral buds. Apples and pears flower and fruit primarily on terminal buds. A terminal, sometimes called the apical bud, is one located at the tip of a shoot. A lateral bud develops along the developing shoot at the base of the leaf blade.
The flower/fruit buds in apples and pears can be terminal on long shoots (greater than 4 inches) or more commonly on short shoots called spurs. A spur is a short shoot (4 inches or less) that only grows a very small amount each year. Spurs usually take 2 years to develop; that is, in the first year the bud is formed as either a lateral or terminal bud. If the bud is terminal, it may flower the next year or it may not. Lateral buds formed the first year may produce a flower, but the fruit that develops is small and of poor quality. More often, the lateral bud may thicken and grow only a small amount and develop as a spur, which may flower in the subsequent years.
The spur and terminal flower buds can have both vegetative and flower components. The buds usually produce about five to eight flowers and a similar number of leaves. Occasionally, a new vegetative shoot will develop after the flowers set fruit.
Pruning and training as described below will affect the amount and type of buds formed by apples and pears. Trees that are very vigorous, whether due to pruning or overfertilization, form fewer flowers.
Apple spur
No comments:
Post a Comment