A Sunny Disposition: Managing Light in Orchard Systems Tom Kon Southeastern Apple Research Specialist
Thank you for the warm welcome to the Southeast!
Why is light important in apple production?
As light interception increases
Outline I. Increasing light interception in orchard systems II. Increasing light distribution in orchard systems I. Mechanization and automation in modern orchard systems
Ida Reds Interstem 9-111 11 x 21 27 yrs old
Practices to increase light interception Increase planting density Reduce distance between rows Increase tree height N S row orientation
Canopy light interception vs. yield (Wünsche and Lakso, 2000)
Size-Controlling Rootstocks
Rootstocks Rootstock selections are site dependent Growers are anxious for greater access to fire blight resistant rootstocks (Geneva Series) TC Vigor of scion, rootstock, and soil dictate in-row spacing
> 30 Named Apple Training Systems 2 spherical canopies 13 are cone shaped canopies 7 are planar (palmette) 8 are V or Y canopies (leaned over cones or palmettes) Managing Light is the key in any system!!
Ida Reds Interstem 9-111 11 x 21 27 yrs old
Tall Spindle near Bolzano Italy
Light Distribution: Even dwarfed trees have a zone of inadequate light! Min. % Full Sun: Flowering: 30% Photosynthesis: 30% Color and Quality:50%
One size fits all? Site / terrain? Irrigation? Business model? Wholesale vs U-pick Processing vs. Fresh Equipment High establishment costs Tree support system Greater risk
Tall Spindle Tall for light interception in single row. Narrow for light distribution, labor access. Planted at 3 x 12 ft - produced 300 bu/acre in year 2!
V Trellis Best light interception Can access with larger equipment High establishment costs
Multi-leader canopies : Bi-Baum
Alberto Dorigoni Univ. Bologna
Canopy light interception vs. yield (Wünsche and Lakso, 2000)
Tustin, et. al
Tustin et. al ~10 ft between trees, ~ 5 to 6.5 ft between rows 674-871 trees/acres Each tree has 10 vertical fruiting stems every 12 inches Vertical fruiting stems 11.5 ft tall In theory, yields 150 200 bins/acre
Outline I. Increasing light interception in orchard systems II. Increasing light distribution in orchard systems I. Mechanization and automation in modern orchard systems
Practices to improve light distribution Spreading/training limbs to a horizontal Annual dormant pruning Summer pruning (watersprouts)
Before T r e e After T r a i n i n g
Pruning: Why is it important? Pruning: cutting away of a portion of a plant for horticultural purposes to modify canopy shape, renew bearing surface, increase light & spray distribution within canopy. Most pruning is done to improve light distribution for increasing fruit quality.
Jim Schupp, Edwin Winzeler, and Melanie Schupp
LCSA/TCSA = 1.75 LCSA/TCSA = 1.00 LCSA/TCSA= 0.50
MD: Maximum Allowable Branch Diameter LT = 1.25 LT = 1.25 LT = 1.25 LT = 1.25 Max. allowable branch diameter Trunk diameter
Summary: Size Matters Goal: to do 70% pruning = 90% benefit We can reach this goal with one rule
Video Imaging for Automation Cameras can see about 2 feet into canopy
Vacuum Harvester
Summary Light interception and distribution plays a key role in physiological processes and orchard productivity Orchard design and Standard cultural management practices New/future plantings: Consider modern / more efficient rootstocks Consider new / future technologies
An Ultramodern Fruit and Vegetable Packing System: New Opportunities in Research and Education Programs Tom Kon, Diane Ducharme, Chris Gunter, Frank Louws, Inga Meadows, Dilip Panthee, Mike Parker, Penny Perkins, Sara Villani, and Jim Walgenbach Project was funded by the College of Agriculture and Life Sciences at NC State! Letters of support: NC Apple Growers Association and Blue Ridge Apple Growers Association
Thank you for your attention and support!