Once we realized the HWA was native to our own country, our hypothesis was that we would have an analogue for every Chinese or Japanese summer predator. All we have to do is collect and release beetles - and our insectaries are now coming on line locally. This program works. We need to get the word out and expand this program to save as many of the High Country's hemlocks as possible. If we can organize quickly we can still save many hemlocks and all the other plants and animals that depend upon hemlocks for survival. Like trout, wood thrush, crayfish, and other 'cool' creatures.

1. Banner Elk & Grandfather Mountain
Banner Elk & Grandfather Mountain
Collections & Observations
Collections & Observations
Dick McDonald

2. Overview Of Hemlock Hill
 Initial release - 300 lab-reared beetles in 2003.
 Recovered 3, 12, 93 beetles in 2004, ’05, ‘06, respectively –
establishment by year 3 – 2006.
 2005-2012 - 695 beetles collected in Seattle area released.
 2006 recovered beetles in non-release areas using “nonstandard” sampling based on where beetles were found in
Seattle
• Beetle dispersal was ½ mile by 2008, 10+ miles by 2012
• 34,500 beetles collected in last 14 months
 Currently using field nurseries as well as Seattle collections
to establish beetles in other areas
 Providing on-site training in different states on sampling
procedures.

3. Initial release of Laricobius nigrinus in NW NC.
Dr. Gina Davis ––recovers 22F1 Ln 16 Oct 2004
Dr. Gina Davis recovers F1 Ln 16 Oct 2004
along with Prof. Stewart Skeate.
along with Prof. Stewart Skeate.
• Dr. David Mausel, Virginia Tech, released 300 Lamb-labreared L. nigrinus adults on 31 Dec 2003 @ Hemlock Hill,
Banner Elk & 150 adults Oct 2004 at Holloway Mountain.
These were two of Dr. Mausel’s 22 release sites on the east
coast. Dr. Gina Davis was the NC state forestry liason for the
NC releases.

4. Site Elevations:
1000 - 1200m
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2
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Intensive study sites of L. nigrinus around Banner Elk
(Date , # adults released, source)
1- Hemlock Hill, Banner Elk 2003-300 VT Lab + 2006-455 Seattle.
2- Holloway Mtn. Rd. 2004-150 VT Lab + 2006 240 Seattle.
3- Lees-McRae Field, Banner Elk 2005-202 adults OSU + 2006 -100 OSU

5. L. nigrinus Dispersal
L. nigrinus Dispersal
Mid-November 2006 ––11adult,
Mid-November 2006
adult,
main ridge of Hemlock Hill,
main ridge of Hemlock Hill,
300+ meters from the nearest
300+ meters from the nearest
release tree.
release tree.
N. Elk River Oct 07
Nov 06
Mar/Dec07
Jan 08 Ln
March 2007 --11adult,
March 2007
adult,
600 meters from nearest
600 meters from nearest
release tree.
release tree.
December 2007 --22adults , ,
December 2007 adults
same area as above
same area as above
January 2008 ––11adult,
January 2008
adult,
800 meters from nearest
800 meters from nearest
release tree and on opposite
release tree and on opposite
site of open athletic field.
site of open athletic field.

6. Dispersal in Banner Elk Area, 2010
Dispersal in Banner Elk Area, 2010
Beetles ½ mile from release site.
Beetles ½ mile from release site.

7. From February 2008-2012, Grandfather Golf and Country Club released 13,000+ wild
From February 2008-2012, Grandfather Golf and Country Club released 13,000+ wild
caught L. nigrinus from Seattle, Washington. A majority of those beetles were collected
caught L. nigrinus from Seattle, Washington. A majority of those beetles were collected
at Seattle Golf Course (a total of nearly 10,000) during 2008 to 2010. It is believed that
at Seattle Golf Course (a total of nearly 10,000) during 2008 to 2010. It is believed that
this amount of beetles has lead to L. nigrinus spreading over 10 miles in all directions.
this amount of beetles has lead to L. nigrinus spreading over 10 miles in all directions.
This was the first large scale, operational release of L. nigrinus on the East Coast.
This was the first large scale, operational release of L. nigrinus on the East Coast.

8. Release Sites
Release Sites
& Recovery Areas
& Recovery Areas
Approximate area
Approximate area
of recoveries in 2012
of recoveries in 2012
Banner Elk
Banner Elk
Grandfather
Grandfather
Golf &
Golf &
Country
Country
Club
Club
Holloway
Holloway

9. Looking North to Beech, Flat Top, Sugar, and
Looking North to Beech, Flat Top, Sugar, and
77Devils Mtns --Peaks and valleys where
Devils Mtns Peaks and valleys where
Laricobius nigrinus has dispersed and is
Laricobius nigrinus has dispersed and is
generally established ––300 square miles.
generally established 300 square miles.
GGCC is in the foreground below.
GGCC is in the foreground below.

10. Looking southwest towards
Looking southwest towards
Hawksbill/Table Rock Mtns,
Hawksbill/Table Rock Mtns,
at the center of the screen.
at the center of the screen.
Ln found at base of Hawksbill
Ln found at base of Hawksbill
On Carolina Hemlocks. Black
On Carolina Hemlocks. Black
Mountains in distance.
Mountains in distance.

11. Cold-hardiness of Laricobius nigrinus
in the mountains of northwestern North Carolina
••Beetlesat the hemlock/spruce-fir tree line on
Beetles at the hemlock/spruce-fir tree line on
Grandfather Mountain at 4,800 feet elevation. Maine?
Grandfather Mountain at 4,800 feet elevation. Maine?
••TheBanner Elk, Grandfather area is in cold-hardiness
The Banner Elk, Grandfather area is in cold-hardiness
zone 6a (-23° C avg. min.). Grandfather: 5,960’ elev.
zone 6a (-23° C avg. min.). Grandfather: 5,960’ elev.
••Beetleswere originally collected in cold-hardiness zone
Beetles were originally collected in cold-hardiness zone
8a (-12° C avg. min.) in Seattle/Tacoma area.
8a (-12° C avg. min.) in Seattle/Tacoma area.
••Beetlesin North Carolina are thriving in a climate with
Beetles in North Carolina are thriving in a climate with
much colder winter temperatures than the climate where
much colder winter temperatures than the climate where
they originated.
they originated.
••Possiblegene flow from interior populations of beetles.
Possible gene flow from interior populations of beetles.

12. Recommendations:
Recommendations:
1)SOP for Ln collections on the East Coast – HWA data base.
1)SOP for Ln collections on the East Coast – HWA data base.
2)Urban community forest interface to collect beetles;
2)Urban community forest interface to collect beetles;
3)Get beetles from NW NC & PNW as needed; (Scw)
3)Get beetles from NW NC & PNW as needed; (Scw)
4)Releases based on knowledge of Ln requisites – duff, sun,
4)Releases based on knowledge of Ln requisites – duff, sun,
5)Use a simple guide sheet explains Ln’s life history.
5)Use a simple guide sheet explains Ln’s life history.
6)Training of cooperators to refine search images, Ln
6)Training of cooperators to refine search images, Ln
phenology, use of UV, and ability to read the landscape to
phenology, use of UV, and ability to read the landscape to
release and then recover predators years later;
release and then recover predators years later;
7) Mason/Dixon effect – abiotic factors – HWA winter kill
7) Mason/Dixon effect – abiotic factors – HWA winter kill
from NJ north; we don’t have that in the South. Aggressive
from NJ north; we don’t have that in the South. Aggressive
southern strategy.
southern strategy.

14. Predators Released in Study Sites
Predators Released in Study Sites
Laricobius
Laricobius
nigrinus (Lari)
nigrinus (Lari)
Sasajiscymnus
Sasajiscymnus
tsugae (St)
tsugae (St)
Scymnus
Scymnus
sinuanodulus (Ss)
sinuanodulus (Ss)

15. What about Scymnus coniferarum?
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Seattle: ‘Scymnus trees’.
We ignored summer predators – focused on Ln.
Lower numbers than Ln (1/10th - collecting during
winter).
Reproduces within tree – Ln must leave tree to pupate.
Habitat: hemlocks that don’t have needle duff (wind).
Parking lots, Golf courses, cemeteries, etc.
Nature: bluffs, rocky outcroppings, mountain ridges,
along rocky creeks/rivers, windy areas.
Alternate adelgid hosts – Pines, firs, spruces.
*BRACKETING- Predator for every life stage of HWA.*

16. Scymnus coniferarum Crotch (Scw) ––Hemlock was new recorded
Scymnus coniferarum Crotch (Scw) Hemlock was new recorded
Host tree and HWA was aanew host. Photo: Nathan Havill USFS.
Host tree and HWA was new host. Photo: Nathan Havill USFS.

17. Collection records of Scymnus (P.) coniferarum based
Collection records of Scymnus (P.) coniferarum based
on museum specimens; shaded = general area of many
on museum specimens; shaded = general area of many
collections with dots showing peripheral localities (from
collections with dots showing peripheral localities (from
Gordon 1985); grey rectangle is area of recent
Gordon 1985); grey rectangle is area of recent
collections in the Seattle area.
collections in the Seattle area.

18. Summer Predators in Seattle
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We collected 956 Scw from Oct. 2009 -June 2010; most (838) of these
were collected in late April (397 adults) and late June (441: 269 larvae and
172 adults).
Scw is widespread in the Seattle-Tacoma area.
Scw appears to be a major summer HWA predator in this area.
We were able to collect more summer predators from trees that do not
favor the development of L. nigrinus. These are trees that have the needle
duff removed (or covered by mulch) and make it difficult for L. nigrinus to
complete its life cycle.
Natural areas: rocky outcroppings, bluffs, windy areas, or trees lining
creeks.
We collected Scw beetles on hemlock trees lacking needle duff in parking
lots, cemeteries, and playgrounds, in mostly urban areas.
24 Scw adults were collected on Western White Pine infested with
adelgids (and aphids) from 3 infested pine trees.
Some niche partitioning between summer and winter predators.
See Dr. Michael Montgomery’s poster on host range of Scw.

20. Recovering Summer Predators back East
• We may want to make releases in areas which
don’t initially favor Ln - ridges, bluffs, other
areas lacking needle duff.
• Alternate adelgid hosts – pines, firs, etc.
• Release into hedges along a parking lot or
similar place urban community forest
interface.
• May disperse faster than Ln?