Apples – For
Goodness Sake:
Thoughts on Orchard
Sustainability
Curt R. Rom
Professor – Horticulture
University of Arkansas
How I got to
this place
A Personal Story
An Arkansas Story
“How important is local food?”
The “carbon costs” of imported apples
Global Climate Change:
Providing Food in a Changing
Climate
http://www.fao.org/wfd2007/index_en.html
“Sustainability 360”
“Environmental stewardship and
Sustainability is good for business
And our customers”
Outline
What?
Wh ?
Why?
Elements
How?
What is Sustainable
Production?
• Many Misconceptions!
What is Sustainable?
“An
An integrated production system having site
site-specific
specific
application that over the long term will
¾Satisfy food and fiber needs
¾Enhance environmental quality and natural resources upon which
the agriculture economy depends
¾Make most efficient use of nonrenewable resources and on-farm
resources and integrate natural biological cycles and controls.
¾Sustain the economic viability of the farm
¾Enhance the quality of life for farmers and society as a whole”
USDA: http://www
http://www.nal.usda.gov/afsic/pubs/terms/srb9902.shtml#toc2
nal usda gov/afsic/pubs/terms/srb9902 shtml#toc2
What is Sustainable?
f
Additional Definitions
– all workable
• Ecological, Economic, and Social Welfare is
Maintained both in the Present and for the Future.
• Current decisions and practices will not negatively
effect but will positively support and sustain future
practices
• Using, Developing, and Protecting Resources at a Rate
and in a Manner that allows us to Meet Current Needs
and to Meet Future Needs
M lti l resources/citations
Multiple
s
s/ it ti s
Types of Sustainability
• Ecological and Environmental
Sustainability
• Agricultural Sustainability
• Economic Sustainability
• Sociological Sustainability
All somewhat inter-related, coincident
Sustainable Agriculture
•
•
•
Is a production philosophy or system
Is not regulated by gov’t
IS regulated
l t db
by b
buyers
– Driven by environmental consciousness
– Driven by consumerism
– Driven by capitalism
Sustainable Agriculture
based agriculture to
• Ecologically
Ecologically-based
minimize environmental impact in order
p
to continue production
– Success metric is not yield exclusively,
• but also agricultural value, environmental value,
social values (families,
(families communities)
– Manage system bio-diversity
Environment partnered with economics
Concerns
• The concerns of orchard sustainability
are
1 Inputs vs outputs
1.
-balance and imbalance
-our
our “carbon
carbon footprint
footprint”
2. Impacts of the farming system
3 The ability to continue farming with
3.
sustained production in the future
IS SUSTAINABILITY AN
ISSUE FOR ORCHARDS?
Orchard Sustainability
Several Issues to Consider
• Productive Sustainability
• Economic Sustainability
Some Key Concepts to
Remember for Sustainability
In order to be sustainable…
sustainable
• Reduce p
pesticide and p
petroleum use in the
orchard
• Focus on soil quality and “health”;
– soil
il ground
d cover and
d nutrient
t i t managementt
•
•
•
•
Integrated Pest Management
Maximize tree “health”
health and potential
Maximizing crop value – not production
Think long
long-term;
term;
– Plan for today, tomorrow, next year and down
the road
1 Get a good start
1.
You can never make
up for a bad start
make-up
• Get a good start by preparing site and soil
– Soil pH
pH, drainage
drainage, quality trees
trees, appropriate cover
crops
– Appropriate cultivar and rootstock
– Appropriate orchard training system
• Rotate crops
• Prepare replant sites appropriately
2 Bigger is not better
2.
• Especially for tree size
• However, Density matters!
Effects of increasing orchard
planting
l ti d
density
it
With increasing orchard system density:
• Tree volume decreases
• Tree
T
surface
f
area increases
i
• Tree surface area:tree volume increases
• LAI increases (m2 lvs/m2 ground)
• Light Interception by the system
increases
Tree Density and Light
With increasing tree density,
density light
interception by the orchard increases
• With increased light interception,
interception increased
photosynthesis (Pn) and carbon fixation
(Palmer and Wunsche, others)
• With increased Pn and carbon fixation,
increased growth
• With light-driven increased growth, increased
yield (Robinson and Lakso, others)
Ligght Interce ption (totaal light/decaade)
Light Interception Depends on
D
Density
it
100
75
50
25
0
100 200 300 400 500 600 700 800 1000 1200
Tree Density (trees/acre)
(after Jackson and Palmer, Palmer, Lakso, Robinson and Lakso, Rom, etc.)
Light Interception is Related
to Yield
Poteential Cumulative Yield
100
80
60
40
20
0
0
20
40
60
80
Total Light Interception over Orchard Life (% of Max)
(After Robinson, and others)
100
Tree Canopy Volume effects
P
Pest
Management
M
• Increased tree density and decreased canopy
volume
q
less pesticide
p
(ai)
( ) in m
many
y cases
• Trees require
• Trees develop better natural resistance
– Poorer habitat for pests
p
– Tougher leaves; higher phenolic content
• Orchard can be sprayed
p y with alternate rows
Planting
g System
y
Affects
Pesticide Use
1800
120
1600
Trees/A
Acre and
Canopy Vol/Tree
1400
1200
80
% of
Pesticide A.I.
1000
60
800
600
40
400
20
200
0
0
P.22
B.9
M.9
M.26
M.7
Sdlg
Rootstock
Tr/Acre
Canopy Vol/tree
Canopy Vol/Acre (%)
Canopy
y Vol/Acrre
(% off Seedlin
ng)
100
1200
120
1000
100
% of
P ti id A
Pesticide
A.I.
I
800
80
600
60
400
40
200
20
0
0
SS/M.9
VA/M9
CL/M26
CL/Sdlg
Rootstock
Tr/Acre
Canopy Vol/Tree
Canopy Vol/Acre(%)
Canopy Vol/Ac
cre
(% o
of Seedlin
ng)
Trees
s/Acre an
nd
Cano
opy Vol/Trree
System May Reduce Cost
Pn, Leaff Phenolic Conten
nt,
Le
eaf Toughness
Tree Environmental Response
Outside
(
(adapted
f
from
G
Garcia
and Rom, 1995))
Distance from Outside of Canopy
Or Light Exposure (% full sun)
Inside
3 Annual Cropping
3.
Annual cropping leads to sustainable yields
• Seek not to maximize yield but optimize
yield
– Stimulate strong bloom
– Prune
P
to
t reduce
d
unwanted
t d blooms
bl
and
d
stimulate growth
– Balance
B l nc crop
c p load
l d and
nd ttree vigor
i
– Provide Adequate pollination
– Crop
C
Load
L d Management:
M
t Fruit
F it Thi
Thinning
i
Crop Load Management
• PGR methods
• Alternative Methods
– LS+FO
LS FO (2+2)
(2 2) att FB
FB+PF
PF
• Mechanical means
Crop Load Management
• Must be done at critical times
– Dormant pruning
– Prebloom
– Bloom
Post Bloom (up to 45-60 days)
“Thinning of fruit for the purpose of improving that which remains is a practice always advised, but comparatively seldom
followed.” “It has been demonstrated time and again that no work in connection with the fruit plantation pays better than
fruit thinning.”
Liberty Hyde Bailey, 1897. Principles of Fruit Growing
Flowering and Fruit Development
Reasons for Crop Load Management
m
g f
• Maximize
average
fruit
size potential of crop
• Optimize crop yield
• Improve bearing
regularity
• Remove
R
fruit
f it of
f llow
quality potential
• Balance reproductive
and vegetative growth
Timing Makes the Difference
Relattive Bene
efit (%)
100
80
60
40
Return Bloom
Fruit Size
20
0
0
30
60
90
Days after Bloom
(after Batjer; Westwood; Williams; Dennis; et al..)
120
150
4 Manage Soils
4.
• An often forgotten part of the orchard
• Soil is more than just a “medium”
Observations of orchard soils
Over the long
term, with extensive
long-term
herbicide use and synthetic fertilizers
– Decrease in soil pH
– Decrease in soil CEC and buffer capacity
– Increase in soil bulk density
– Decrease in water infiltration rate
– Decrease
D
s in
i water
t h
holding
ldi capacity,
it esp
s iin
the available water range
– Complex effects on soil biology
Soil Health
An old concept with new attention
• Beyond Soil Nutrient Content
• Interested
I t
t d iin balance
b l
of
f soil
il bi
biological
l i l
activity
– Fungi, bacteria, algae, etc.
– Maintaining soil aggregate integrity
– Sustaining soil chemistry
5 Reduce Stresses
5.
• Environmental stress may increase with the
global warming we are experiencing
– Can expect
p
more water stress
• Episodic flooding
• Periodic droughts
• Potential for increase temperature stress and
sunburn
– Fluctuating temperatures,
temperatures esp at transition
seasons
• Possible increasing
g pest
p
pressures
p
Pest Stress
• Sustainable orchard production requires an
active IPM program
– High
g management
g
intensity
y
• Scouting, trapping, record keeping
– Minimize pesticide use
– Use
U minimal
i i l iimpact,
t ““soft”
ft” pesticides
ti id
– Use alternative methods of control
• Appropriate cultivar selection
• Ground cover management
• Maintaining beneficials
Better Strategies for Pest
M
Management
t
• In Order to Reduce Pesticide Use
• We Must have and use new cultivars with
– Multiple
M l l Disease
D
Resistances
R
• Fireblight, Scab, Mildew, Rust, Summer Diseases
– Insect
I
tR
Resistances
i t
• Unexplored genetic potential
6 Grow for your Market
6.
Many strategies for
sustainable markets
– Going “Glocal”
Glocal
• thinking globally,
acting locally
– Growing
g “Locavars”
“Nothing beats a MN
‘Honeycrisp”
Are we sustainable?
Understanding and Measuring
Y
Your
S
Sustainability
i bili
Different than measuring production efficiency
• Means of measuring production efficiency
– Yield compared
p
to total production
p
costs
• Yield compared to energy inputs
• Yield compared to your carbon inputs
– Yield/petroleum
– Yield/pesticides
– Yield/fertilizers
Yi ld/f tili
• Yield compared to your management time
Efficiency vs Sustainability
• Efficiency tells you how you are
currently doing
• Sustainability also predicts how you will
do in the future
Can you measure sustainability?
• Some possible methods
– Yield and pack-out
• Fruit are sensitive indicators
Productio
on Efficienccy
– Long term efficiency evaluations
Years of Operation
p
Sustainability
S
Score/Report
/R
t C
Cards
d
• Many buyers are requiring completion of
and submission of a sustainability
Report Card”
Card or “Score
Score Card”
Card
“Report
– To
T buy
b product,
d t you mustt make
k a “B”
average of have an average score of min.
82.
82
Sustainable Score Cards
• Rate various aspects of the enterprise
Criteria
Grade
–
–
–
–
–
–
–
–
–
–
–
–
–
Yield and quality
Soil health and quality
Pl t health
Plant
h lth
Pollution output
Energy
gy use, conservation, recovery
y
Alternate energy production
Pest mgmt: Pesticide and fertilizer use
Inputs: on
on-farm
farm vs off
off-farm
farm
IPM
Worker welfare
F il welfare
Family
lf
Community Impact
Etc.
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Take Home Message
• Sustainability is important to us as
orchard managers
– We must manage for today,
today tomorrow and
next year
– It is good for business
• Good for customers; good for the environment
• Focused on sustained business
Take Home Message
• Remember Good Horticulture
– Get a good start
– Maximize light interception and distribution
– Sustain annual cropping; optimize yields
– Think about and manage your soils
– Reduce tree stress
– Grow
G
for
f your market
k t
– Score yourself
Thanks for your attentions