theory, practice and examples of using native organisms and organism systems to control invasive non-native plants vs. traditional biocontrol

1. Locating and Using Native
Biocontrols for Invasive
Non-native Plants,
a New Paradigm.

2. ABSTRACT: The debate over using classical biocontrol
to control invasive non-native organisms is redundant
and stale. Instead of searching for new methods and
synergies, the debate is over the pros and cons of
classical biocontrol. This presentation will offer
examples of native biocontrol systems. At the same
time it will offer practical insights into finding native
biocontrols for non-native invasive plants. The goal of
this presentation is to help end the continuing
unethical and scientifically flawed introduction and
use of non-native organisms in hopes of controlling
other non-native organisms.

3. Richard Gardner
rtgardner3@yahoo.com
(410) 726-3045

4. Walk more
Tinker less

5. Most issues in ecology can be
understood by walking.

6. Therefore the most important trait
of an ecologist – loving to walk.

7. Baseline philosophy

8. We are not the center of creation
and its ultimate result.

9. Time is the most important
character of biocontrol.

10. Human time is irrelevant.

11. Ecological/evolutionary time is the
only relevant time.

12. What humans do wrong in human
time takes ecological/evolutionary
time to fix.

13. The same human centered
mistakes that caused the problems
cannot solve them.

14. Basic Concepts

15. Population
Native biocontrol
Non-native
invasive
Native congeners of
non-native invader
time
The expected population curves for native biocontrol use. The baseline population for native
organisms changes as the native biocontrols adapt to the non-native invasive and eat a few
more of the native while the system comes back into balance as the non-native is destroyed.
There is some recoverable risk to the native ecosystem, but not the unrecoverable risk of
introducing non-native biocontrols.

16. Population
Non-native biocontrol
Non-native invasive
Native congeners of
non-native invader
time
Simplified expected curves for what happens when a non-native biocontrol is
introduced after the establishment of a non-native invasive.

17. Population
Non-native
biocontrols
Pioneer non-
native invasive
Native congeners of
non-native invasive
time
Secondary non-native invasives
A more complex version of what happens when a (pioneer) non-native plant is introduced
followed by its non-native biocontrol. The native system collapses allowing secondary non-
natives to enter.
Native organisms

18. Populationor
concentration
Non-native
specialist biocontrol
Non-native invasive
Chemical defenses of
non-native invasive
population
time
This diagram demonstrates what happens when a non-native specialist biocontrol is
reintroduced to its non-native host.

19. Basic terms:

20. Classical biocontrol – the use of non-native organisms
in the attempt to reduce the effects of other non-native
organisms on ecosystems. This is a losing proposition
as it does not attempt to remove the problems, just
reduce their effects.
Bioeradication – the extinction of a non-native invasive
from an ecosystem using native biocontrols, the goal.
This is a winning proposition as it is the regeneration of
the ecosystem by eliminating the problem from the
ecosystem using the available native organisms.

21. Biocontrol – any organism in any time frame from
seconds to centuries that partially or fully inhibits a
non-native organism. Usually the goal of using non-
native biocontrols on non-native invasives. This is a
losing proposition.
Biocontrol system – a group of organisms which
through any biological relationship partially or fully
inhibits a non-native organism.

22. Direct biocontrol – use of a native organism or system
as a biocontrol for a specific organism.
Indirect biocontrol – providing the native resources
such as food, breeding sites or shelter needed for a
native biocontrol or biocontrol system to develop for a
specific organism.

23. Biocontrol garden – a garden of local native plants that
provide a resource that a native biocontrol needs to be
effective as a biocontrol such as food, egg laying sites,
overwintering sites, protection from predators, …, in
any life stage.
Biocontrol resource – any local naturally occurring
environmental resource a native biocontrol needs to be
effective as a biocontrol.

24. Resource familiarity – the amount of use of a resource by a
native biocontrol. In the case of non-native resources
(invasive) it requires time for a native biocontrol to adapt to it
through either behavioral or genetic changes.
Resource use – the use by a native biocontrol of a native or
non-native resource. In the case of a non-native resource it
takes time to adapt to using it through either learning to use
it (behavioral changes) or genetic changes, often both.

25. Resource heritage – the passing on of a social or genetic
adaptation to a resource by a native biocontrol. This can be
through learning, by genetic change or more probably a
combination of both. It can spread through a species
horizontally as one organism learns from another or vertically
as it is passed on to/through offspring through learning or
genes.

26. Mutualism – two or more organisms which cooperate
to the benefit of each other.
Commensalism – two or more organisms living
together where at least one benefits and the effects on
other organisms are neutral.
Competition – relationships where certain organisms
benefit through a variety of mechanisms to the
detriment of others without necessarily using them as
an energy source.
Herbivory, predation and parasitism – relationships in
which one organism or groups of organisms benefit by
using other organisms as an energy source.

27. In Biocontrol/Bioeradication we are trying
to understand all these relationships within
an ecosystem and use them to find native
organisms to hinder and eradicate non-
native organisms.

28. Examples of apparent
biocontrol systems and
potential biocontrol
systems.

29. Ailanthus altissima, the system
I know best.

33. bark herbivory by
Atteva aurea larva

36. This photo shows herbivory, disease and the effects of A. ailanthii. A
few meters away is a meadow of Solidago canadensis which was a
nectar source for A. aurea adults and probable mating site.

39. Rose rosette disease, the system
I am getting to know.

40. Rosa multiflora, Multiflora Rose
with rose rosette disease.

42. Other possible systems I see while
walking.

43. fd
disease
herbivory
Loniera japonica,
Japanese honeysuckle

45. Lonicera morrowii, Morrow’s honeysuckle
stressed leaves, the result of
disease and/or herbivory

46. herbivory
Lonicera maacki, Amur honeysuckle

47. herbivory and
disease?
Elaeagnus umbellata,
Autumn Olive

48. • A family of plants with native congeners.
• Birds move between stands carrying Aculops ailanthii mites
with them.
• Atteva aurea females pick up and move Aculops ailanthii
between trees while laying eggs on various trees.
• Atteva aurea carries disease ingested as a larva, incubated as a
pupa and deposited as an adult on leaves while laying eggs.
• Disease enters tree through the feeding wounds of Atteva
aurea larvae on branches and leaves.
• Disease is carried by the Aculops ailanthii.
• Pollinators also carry Aculops ailanthii between trees.
• Wind carries Aculops ailanthii between nearby trees.
Ailanthus altissima

49. • Large family of plants with native congeners from which diseases
and herbivores can become biocontrols.
• Birds move between bushes carrying Phyllocoptes fructiphilus
mites between them.
• Rose rosette disease, an Emaravirus, is carried by Phyllocoptes
fructiphilus.
• Birds move mites between the bushes which they also nest in.
• Pollinators carry mites between parts of the same bush and
nearby bushes.
• Pollinators also carry mites between bushes.
• Wind carries the mites between nearby bushes.
Rosa multiflora:

50. • Large family of plants with native congeners.
• Disease is carried by mites.
• Deer carry mites in a way similar to ticks.
• Deer browse on local vegetation as a source of food, use the
shrubs for cover and move between stands of shrubs as they
move between environmental resources.
• Birds move mites between the shrubs in which they roost, nest
and feed on the fruit.
• Pollinators carry the mites between shrubs.
• Wind carries the mites between nearby plants.
Lonicera morrowii: possible scenario

51. Most likely scenario for the movement of Aculops
ailanthii and pathogens across landscapes
Birds – long distances searching for familiar shelter during migrations.
- medium and short distances between nearby stands.
Atteva aurea – mostly medium and short distances between egg laying sites.
Wind - short distances within stands and between close stands with high mite densities.

52. Probable scenario for the spread of rose
rosette disease across the ecosystems.
Birds - long distances searching for food and shelter during migrations.
- medium distances between nests and food sources.
- short distances as part of normal random movement.
Pollinators - medium and short distances between food sources.
Wind - short distances within stands and between close stands.

53. Deer - mostly within and between thickets in the short and medium distances.
Birds - across long distances through migration, medium distances while searching
for food and short distances while using the plants as shelter and nesting locations.
Pollinators - across medium and short distances while moving between flowers.
Wind - across short distances primarily within thickets.
Possible scenario for the movement of biocontrol pathogens
and insect herbivores between Lonicera morrowii plants.

54. The more native congeners the more
apt the native biocontrol system is to
form and the more complexity
possible.

55. As complexity increases so does the
probability of a control system and the
more stable the system is.

56. Complexity may involve multiple food sources,
multiple families of organisms which contribute to
control but do not directly control the target,
multiple types of plant use (herbivory, pollination,
nesting and roosting sites, disease), multiple types
of control organisms such as mammals, birds,
insects, diseases and different feeding strategies
(browsing, grazing, nectarivory, frugivory, parasitism
among others) .

57. Reintroducing a coevolved
herbivore specialist to its
original host will fail.

58. By inference, this has been
shown with wild parsnip,
Senecio jacobaea.
(Zangerl, et al, 2005)

59. WhenTyria jacobaeae, one of its
specialist biocontrols from
Europe was accidently
reintroduced after at least 230
years,

60. the chemical defenses
reasserted themselves.

61. In other words, the highest
fitness level of the plant shifted
from its original chemical
defenses to growth and
reproduction in the absence of a
specialist herbivore as it
invaded a new ecosystem, i.e.
enemy release.

62. When the herbivore was
reintroduced, the highest fitness
level shifted back towards using
the original or similar chemical
defenses at the cost of energy
expended for growth and
reproduction.

63. Since the genes for the original
chemical defenses were already
present, turning them on was
easy.

64. It did not involve the much
slower process of evolving
defenses to a new threat.

65. The energy output shifted away
from defense in the absence of
many of its specialist
herbivores.
It then shifted back when the
specific herbivore was
accidently introduced from
Europe.

66. Since the chemical defense
reversion was small because
the threat was small, the plant
continues to thrive as an
invasive.

67. Examples of catastrophic
failures by introduced
biocontrols:

68. The moth Cactoblastis cactorum
was introduced in the island of
Nevis in Caribbean to control
Opuntia monacantha (Willd.)
Haw. in 1957 (Pemberton, 1995).

69. Now it is spreading throughout
the Caribbean eating native
congeners. It is only a matter of
time before it reaches North
American Opuntia species.

70. The weevil Rhinocyllus conicus was
introduced to control Canada
thistle, Cirsium arvense. Instead it
jumped to native thistles. This has
put several of them in danger of
extinction.

71. Example of already present
organisms controlling a non-
native:

72. Euhrychiopsis lecontei,
a native North American weevil
prefers the exotic aquatic plant
Eurasian watermilfoil
Myriophyllum spicatum over
native watermilfoils.
(Sallie P. Sheldon, Robert P. Creed, Jr, 2003)

73. This was expected as the non-
native had no defenses to the
native generalist herbivore.

74. The key to finding a native
biocontrol (system) is to find an
organism which a generalist
(herbivore) that feeds broadly
on a family or genus and a
specialist (herbivore) to that
feeds only on that family or
genus.

75. This means that the biocontrol
has a the genetic ability to
switch from one plant to another
and yet will not cause the
extinction of coevolved food
sources.

76. The necessary conditions for a biocontrol
system:
• food sources for all organisms at all life
stages
• shelter for the various life stages
• breeding sites and egg laying locations

77. 1.) plant biocontrol garden of a wide variety of
mostly Asteraceae seeds to determine
which plants Atteva aurea uses as nectar
sources.
2.) culture and identify to family the diseases
which affect Ailanthus.
3.) walk a lot to continue finding and
understanding native biocontrol systems.
Path forward/2013 research plan:

78. Ailanthus altissima biocontrol garden
2. Aster laevis 1. Asclepias tuberosa
4. Erigeron speciosus 3. Aster novae-angliae
6. Eupatorium perfoliatum 5. Eupatorium maculatum
8. Monarda fistulosa 7. Heliopsis helianthoides
10. Rudbeckia laciniata 9. Rudbeckia hirta
12. Solidago canadensis 11. Rudbeckia triloba
14. Solidago rigida 13. Solidago nemoralis
16. Verbesina alternifolia 15. Solidago speciosa
18. sunflowers 17. Asclepias syriaca
19. Coreopsis 20. Shasta daisy
21. sweet peppers 22. sweet peppers
23. sweet peppers 24. Eu. mac./Cor.
trip./Ech. pur.
25. Collected plants
pasture uphill driveway

79. Non-native biocontrol has high
rates of failure and low rates of
success, an average of 2.44
introduced organisms for every
species on which control is
being attempted.

80. Using natives to control non-
natives is a much lower risk and
therefore safer than using non-
natives to try to control non-
natives.

81. Non-natives, regardless of how
much they are studied have a
high risk associated with them
as is seen by the introduction of
non-natives in the first place.

82. Collateral environmental effects are unknown
with non-native biocontrols such as:
• breeding site competition with natives,
• acting as food supplements for native
predators which shifts population
balance,
• susceptibility to native diseases or
magnifying them in the local ecosystems
as a disease sink,
• disease vectoring and … .

83. Whereas with native
biocontrols, the collateral
environmental effects are known
or predictable.

84. 1.) is safe
2.) is ethical
3.) is necessary
4.) that they understand the problems they are
trying to solve
5.) that they understand the total consequences of
their apparent solutions.
6.) that they have spent time in the field to prove
that there are no possible alternatives
already present.
I challenge the developers of non-native
biocontrols to prove that what they are doing:

85. If bad theory and bad practice
caused a problem, then bad
theory and bad practice are not
going to solve it.

86. One small mistake with a non-native is the
bioecosystem equivalent of a Chernobyl, even
though more subtle.

87. Are we willing to risk that when
there are already good theory
and good examples in place to
guide us?

88. Facebook:
Ailanthusresearch
Biocontrol/