arboriculture and urban forestry start in the nursery · book: illustrated guide to pruning, third...
TRANSCRIPT
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Arboriculture and urban forestry start in the nursery
Dr. Ed Gilman, ProfessorUniversity of Florida
Web site: google Ed Gilman
Book: Illustrated Guide to Pruning, third edition, 201242/section
Outline for today
• Why prune• Tools• Production pruning research• Quality liners• Year one and two – trunk• Year two and three - trunk and crown• Year three and four - crown
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Urban forest friendly nursery tree structure?
cone
cylinder
branch
Codominant stemsBranches should remain smaller than the trunk
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Go to two videos in photos / Aspect ratio
Prune at planting
Here’s why
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Prune at planting
Here’s why
1) Does the tree have urban forest compatible architecture?
Prune at planting
Here’s why
2) Is that tree likely to receive formative (structural) pruning routinely in the next 15 years?
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No pruning at planting: watch what happens-
No pruning at planting: watch what happens-not compatible
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Large pruning cut was required for clearance
Large cut (20 cm)
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Big cuts can result in decays
and|cracks
Several years later, without pruning
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Both stems were on the tree at planting. One should have been removed or shortened.
Trees can fail
when youngBoth stems were on the tree at planting. One should have been removed or shortened.
1/4
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Trees can fail
when youngBoth stems were on the tree at planting. One should have been removed or shortened.
Codominant stem with inclusion was on the tree in the nursery
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Broken branches were on the tree in the nursery
Crack!
Broken stem was on tree at planting. It should have been removed or shortened.
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Large aspect ratio
Photo series Brian Kempf and Ed Gilman
Preventing damage by shortening one at planting.
Large aspect ratio 2 years later
Photo series Brian Kempf and Ed Gilman
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Large aspect ratio 2 years later
Photo series Brian Kempf and Ed Gilman
5 years after initial pruning
Small aspect ratio
Photo series Brian Kempf and Ed Gilman
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5 years after initial pruning
Small aspect ratio
Photo series Brian Kempf and Ed Gilman
5 years after initial pruning
Photo series Brian Kempf and Ed Gilman
At planting
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Dominant leader vs. Several leaders
Photos Brian Kempf
Trees with several leaders are difficult to raise. Sprouts will grow to block signs again. Encourages poor form.
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Dominant leader trees are easier to raise or lift the crown for clearance, and stronger.
Before AfterPrune at planting
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We can take some lessons from the Malusprofession: nice central leaders
We can take some lessons from the Pistacia and Juglans profession: nice central leaders
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Outline for today
• Why prune• Tools• Production pruning research• Quality liners• Year one and two – trunk• Year two and three - trunk and crown• Year three and four - crown
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Outline for today
• Why prune• Tools• Production pruning research• Quality liners• Year one and two – trunk• Year two and three - trunk and crown• Year three and four - crown
GoodNO You must
be kidding
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Trees too close and no low branches
I don’t want this -
branches were
shortened by the whip/liner
producer.
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Yes
Yes
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Yes
Outline for today
• Why prune• Tools• Production pruning research• Quality liners• Year one and two – trunk/branches• Year two and three - trunk and crown• Year three and four - crown
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Our trees Growers treesOur trees
Our trees
Thick trunk
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Our trees
Thick trunk
Growers trees
Thin trunk
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Growers trees
Thin, weak trunks
Montreal municipalnursery!
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Montreal municipal nursery!
Temporary branches
Befo
re After
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3/4
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Reduction cut is the key After
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No one wants to buy a stick, so trees are headed
Heading cut
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These should have been reduced earlier
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These were reduced
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Outline for today
• Why prune• Tools• Production pruning research• Quality liners• Year one and two – trunk / branches• Year two and three - trunk and crown• Year three and four - crown
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- Thicken the trunk
- Develop the canopy
Good quality second year tree
Leave low branches on the trunk, perhaps remove some of the largest
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Manage low temporary branches to thicken trunk
Remove for herbicide
Increase caliperIncrease root growthReduce over extension of leader
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- Thicken the trunk
- Develop the canopy
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Reduce aggressive canopy branchesBefore after
Reduce aggressive canopy branchesBefore after
No low branches needed pruning
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Before After
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Outline for today
• Why prune• Tools• Production pruning research• Quality liners• Year one and two – trunk/branches• Year two and three - trunk and crown• Year three and four - crown
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Before After
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Before After
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Before After
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Let me know if I can help you
Dr. Ed Gilman, Professor emeritusUniversity of Florida
Web site: google Ed Gilman
Book: Illustrated Guide to Pruning, third edition, 201242/section