Integrated Pest Management at
Longwood Gardens
Grant Jones
IPM Specialist
Outline
• Longwood’s IPM Program
• Key Pests
– Hemlock Woolly Adelgid
– Taxus Decline
– Emerald Ash Borer
– Beech Decline
• Turf IPM
IPM at Longwood
• Insects/Disease/Abiotic Problems
• Algae
• Mice
• Geese
• Misc
IPM Staff at
Longwood
• 2 full time
• 1 intern
• 1-3 students/interns
per month
Integrated Pest Management
Sustainable approach to managing pests by
combining Biological, Cultural, Physical, and
Chemical tools in a way that minimizes
economic, health, and environmental risks.
Choice of tactics is based on effectiveness,
environmental impact, site characteristics,
safety, economics, and client
expectations/preferences.
Cultural Control
Biological Control
Chemical Control
Pest Management Strategies
• Mission: The IPM group strives to reduce the
impact of living organisms on Longwood's plants,
infrastructure, and people using sustainable yet
effective approaches
• Always use the least toxic, yet effective method
to control pest problems
• Growing healthy plants for a superior display
Outdoor Scouting
Slide from Rachel Schnaitman
Outdoor Scouting
• Growing Degree Days
• Pheromone Traps
Slide from Rachel Schnaitman
End Results
• Once Report is completed, meet with the
gardener/grower to develop an IPM Plan.
• What techniques are available?
Slide from Rachel Schnaitman
Pest Prediction:
• By calendar-based treatment programs
• Periodic plant inspections
• By Growing Degree Day (GDD) models
– A method of tracking heat unit
accumulation
– “Physiological Time”
• By Plant Phenological Indicators (PPI’s)
– Leaf or Flower bud swell/bud break
– Bloom, Full Bloom
– Petal Fall, Post Bloom
2014 Growing Degree Days @ LG
Determining/Using GDD’s:
Website: http://www.weather.com/outdoors/agriculture/growing-degree-days/
Phenology
• Instead of GDD,
indicator plants are
used to predict pest
activity
– Removes some of the
temperature variability
• Ex. Treat for gypsy moth
when black cherry first
blooms
Phenology
Scouting Cheat Sheets
Pesticide Selection
• Try to minimize impact to beneficial insects
when possible
– Avoid broad spectrum
– Use products softer on beneficial insects
• Azatin, Horticultural Oil
Management of Key Pests
Hemlock Woolly Adelgid
• Two generations per year
• Overwintered nymphs swell
early in season and molt to
adult stage, producing eggs
• Eggs hatch and turn into
small “crawlers”, which
settle and feed at the base
of the needle petiole (~June)
Hemlock Woolly
Adelgid
• Previously used 2%
horticultural oil
• Challenges:
– Labor intensive
– Weather dependent
– Soil compaction from
equipment
Revised HWA Plan
Include alternative
treatments (imidacloprid
soil injection and
dinotefuran bark spray)
Alternative treatments
selected for:
• Older trees
• Difficult to reach trees
• Poor health
Pollinator Concerns
• Hemlock’s are wind pollinated
• Students/Interns would
measure tree DBH and if
flowering plants were nearby
– Imidacloprid soil injection used if
no flowering plants nearby
– Dinotefuran bark sprays used if
flowering plants nearby
Treatment Type
Safari Bark Sprays
Zenith Soil
Injections
2% Horticultural
oil applications
Treatment Dates
April 2014
May 2014
# of Trees
52
28
June-August 2014
40
Total
Safari Bark Sprays
Zenith Soil
Injections
2% Horticultural
oil applications
April 2015
May 2015
120
20
-
June-August 2015
40
Total
60
Prior to 2014 approximately 140 trees
were treated annually
Taxus Decline
Taxus Decline
• Taxus decline is caused by:
– Excessive soil moisture and/or infection by
phytophthora root rot
Slide from Matt Taylor
Taxus Decline
• This can be
exacerbated by:
– Compacted soil
– Poor drainage
– Root disturbance
– Improper fertility
(pH and nutrients)
Slide from Matt Taylor
Early Symptoms
• Needle Yellowing
• Needle Drop
• Death of branches
Slide from Matt Taylor
Taxus Monitoring
• Soil and tissue samples of all plants
considered significant.
– Collected in spring by soil lab volunteers
• Spring and summer fungicide applications
– Preventative and on symptomatic plants
– Subdue Maxx drench once soil temps are above
70 °F
Slide from Matt Taylor
Taxus Maintenance
•
•
•
•
•
Avoid excessive irrigation
Use coarse mulch and apply sparingly
Manage pH to be between 6 – 7
Fertilize according to spring soil tests
Inform IPM of any significant changes
– Positive or negative
Slide from Matt Taylor
Slide from Ed Broadbent
Emerald Ash Borer
Emerald Ash
Borer
-
Existing inventory of
ash trees
-
Evaluated based on:
-
Tree condition
-
Surrounding
plantings
-
Site Culture
-
Overall design intent
Emerald Ash Borer
- Selected six trees in the garden and 20 trees in
the perimeter areas to protect
- Began treating with Emamectin benzoate in
2012 on a two year basis
- Trees are staggered to balance treatments
between years
- Several replacement tree options were selected
for each ash tree, protected and not protected.
Beech
Allée
Bleeding Canker
of Beech
- Phytophthora
canker attacking
European beech
- Can be caused by
one of three
Phytophthora spp
Bleeding Canker
of Beech
- Treat with Agri-Fos +
PentraBark in the
spring
- Annual survey
noting tree health
and canker size
Granulate Ambrosia Beetles
Granulate
Ambrosia Beetle
• Vectors fungus which beetle
feeds on
• GDD 300-800 GDD – or when
temps reach 70 F
– Multiple generations
Pheromone
Traps
- Use pheromone
traps to identify
periods of peak
flight
- Treat lower trunk
of the tree with
permethrin
Turf IPM
• Groundskeepers break the garden down into
smaller sections
• Each section is prioritized based on the
tolerance for weeds
• Scout for weeds while mowing
• Use cultural practices
Turf IPM
• Herbicides applied if needed
• Lower weed tolerance in high traffic areas
• Goal is not to reapply herbicides to a section
for several years
• Herbicide usage has decreased by 75% since
2006
Tools for an IPM Program
Public review until Jan 12, 2015
ISA Representatives are Rich Hauer and Sharon Lilly (Alternate)
More info at http://tcia.org/business/ansi-a300-standards