Greetings, learners!
This activity will cover the pruning of dwarf varieties of apple trees for backyard growing - specifically spur strains. According to Carroll Calkins, the editor of the Reader's Digest Illustrated Guide to Gardening (1995, p. 494):
Some varieties produce most of their fruit on short growths known as spurs...But some varieties also produce fruit on one-year shoots (tips), both terminally and laterally. ..We now have so-called spur strains, and these trees make about one-third less growth and are heavily laden with spurs. "Golden Delicious," "Red Delicious," "McIntosh," "Rome Beauty," and "Winesap" are available as spur strains. For backyard apple trees on dwarfing stocks, the spur strains are recommended.Why Prune?
We prune apple trees to improve the quality of the fruit, to maintain the health of the tree by removing dead or diseased wood, and to prevent limb breakage from too many fruits on one branch (Calkins & Miller, 1995, p. 488). In the first few years of a fruit tree's life, the tree will be pruned with the purpose of establishing strong branches in the desired shape for bearing fruit (Calkins, 1995, p. 494). According to Calkins, "Apples, sweet cherries, and pears bear fruit mostly on wood that is at least two years old" (1995, p. 489). After a young tree is established, says, "...the aim is twofold: to keep the tree open to light and air and to maintain the right balance between growth and fruitfulness" (1995, p. 494). Often a tree will be several years old before purchased. Before pruning, it will be necessary to determine the age of the branches to be pruned by examining the branches. To understand what you are seeing, we will define a few terms.
Shoot - a newly grown aerial part of a plant, e.g. a leaf bud or branch (Encarta Dictionary in Microsoft Word)
Spur - a short growth or lateral shoot from a from a stem or a branch of a plant (Encarta Dictionary in Microsoft Word)
Tip - one-year shoots from a branch
Leader - the leading shoot of a branchLateral - a side shoot from a branch
Fruit buds - large, round buds that will first blossom, then become fruit Growth buds - smaller and flatter than fruit buds, these will produce new shoots (Calkins, 1995, p. 494)
Competing leader - a branch coming off of the main trunk then growing vertically in competition with the trunk
Sucker - a shoot growing up from the base of the tree
Sucker - a shoot growing up from the base of the tree
(figure reproduced from Calkins, 1995, p. 494)
In the image above you can see a Lateral and a Leaders as well as images and descriptions of Spurs, Fruit buds, and Growth buds.
When to Prune
The correct time to prune depends upon the purpose for pruning. Mature fruit trees should have old, dead, or diseased wood removed during the summer (Morgan 1997, p. 245). If you are trying to encourage more fruit, pruning in the summer after the new growth appears, can promote fruit buds (Calkins, 1995, p. 494). Pruning in early fall will prevent disease from entering the wounds. Calkins says, "Winter pruning (late fall to late winter) promotes growth by directing energy to growth buds at the expense of fruit buds" (1995, p. 494).
How to Prune
For most pruning, you will use small hand shears ( Europeans call them secateurs) with curved bypass blades. Anvil-type shears (they have a blade that pushes against a metal sole) crush the stems and leave a stub that can encourage disease (Calkins, 1995, p. 245). A regular, toothed pruning saw is good for branches over one inch in diameter. For anything over five inches, a chainsaw is probably your best bet. It is important when pruning diseased or infested wood to dip the blades of your shears into a bleach solution (1:10 ratio of bleach to water) to prevent spreading the problem to unaffected wood (Cook on This Old House video).
Watch the videos on the link below, paying special attention to the sections dealing with fruit buds. Close the first video when it finishes, return here to view the second video, then return here once again for a summarizing activity.
Now that you have watched the videos, click on the link below to go to the Survey Monkey website for a summarizing activity.
Return here once you have finished.
We will continue with a practice activity. Click on the link below for a PowerPoint presentation.
Now that you have finished practicing, it's time to test your knowledge. Click on the link below to go to the Survey Monkey website again for your assessment. Don't forget to return here afterward.
All finished? I hope you have enjoyed this activity. If you are interested in further information on this subject, see the links below.
Blog by Stephen Hayes of Fruitwise Orchard
References
Calkins, Carroll C., editor (1995). Reader's Digest Illustrated Guide to Gardening. Pleasantville, N.Y.: Reader's Digest Association
Morgan, Barbara J., editor (1996). 1001 Hints & Tips for Your Garden. Pleasantville, N.Y.: Reader's Digest Association