Gratiana bolivianaGratiana boliviana Releases in Georgia and Releases in Georgia and
AlabamaAlabama
Amy Roda and Stephen HightAmy Roda and Stephen HightUSDA APHIS PPQ CPHSTUSDA APHIS PPQ CPHST
USDA ARS CMAVEUSDA ARS CMAVE
GoalsGoalsEstablish populations tolerant of Establish populations tolerant of
northern conditionsnorthern conditionsCreate field insectaries to serve as Create field insectaries to serve as
source for other northern locationssource for other northern locationsDevelop a method to evaluate the Develop a method to evaluate the
impact of impact of Gratiana bolivianaGratiana bolivianaEvaluate the impact of Evaluate the impact of Gratiana Gratiana
bolivianaboliviana
Evaluation -1x1 m patchEvaluation -1x1 m patch
Count all plantsCount all plants Measure the five tallest plants Measure the five tallest plants % composition that TSA% composition that TSA Count fruitsCount fruits PhotoPhoto GPS centerGPS center
Evaluation -100’ LineEvaluation -100’ Line20052005
# of branches crossing line# of branches crossing line
2006 added2006 added
1 m swath each side line1 m swath each side line
height of plantsheight of plants
% TSA of area% TSA of area
# fruits & flowers# fruits & flowers
# larvae & adults# larvae & adults
Kenny’s Site, Coffee Co. ALKenny’s Site, Coffee Co. AL20052005 2,650 beetles released2,650 beetles released Transect set – 2 lines with 6 1x1 m patchesTransect set – 2 lines with 6 1x1 m patches
20062006 Beetles survived winterBeetles survived winter 2,350 beetles released2,350 beetles released
20072007 Beetles survived winter, located on site edgesBeetles survived winter, located on site edges No beetles releasedNo beetles released
June 06June 05 June 07
0
20
40
60
80
100
% Comp Height (cm) # Fruit # Crossings
June 05June 06June 07Nov 05Nov 06
Kenny’s Site, Coffee Co. ALKenny’s Site, Coffee Co. AL
Brook’s Site, Geneva Co. ALBrook’s Site, Geneva Co. AL
20052005 2,650 beetles released2,650 beetles released20062006 Beetles survived winter despite Beetles survived winter despite cultural practicescultural practices 2,350 beetles released2,350 beetles released Transects set – 6 linesTransects set – 6 lines20072007 Beetles survived winter, Beetles survived winter, located ca. 100 m from releaselocated ca. 100 m from release 1,850 beetles released site edges1,850 beetles released site edges
June 05
June 06
Mapleville Site, Chilton Co. AL Mapleville Site, Chilton Co. AL
20062006 3,300 beetles released Aug.3,300 beetles released Aug. Individual plants measured (height, width, length)Individual plants measured (height, width, length)
20072007 Beetles survived winter Beetles survived winter 3,000 beetles released3,000 beetles released Transects set – 4 lines Transects set – 4 lines
August 06 June 07
Herd Farm-Trail Site, Bainbridge, GAHerd Farm-Trail Site, Bainbridge, GA20052005 2,600 beetles Decatur Co.2,600 beetles Decatur Co. Transect lines – only crossings countedTransect lines – only crossings counted 1X1 m patches 1X1 m patches 20062006 Beetles survived winter/cultural practicesBeetles survived winter/cultural practices 1,0001,000 beetles releasedbeetles released20072007 No beetles found No beetles found No beetles releasedNo beetles released
June 05
June 05 June 06 June 07 June 06
0
20
40
60
80
100
% Comp Height Fruit Crossings
June 05June 06June 07Nov 05Nov 06
Herd Farm-Trail Site, Bainbridge, GAHerd Farm-Trail Site, Bainbridge, GA
Herd Farm-Pond Site, Bainbridge, Herd Farm-Pond Site, Bainbridge, GAGA
20062006 Site located in AugSite located in Aug Transects set – 4 linesTransects set – 4 lines 1,0001,000 beetles releasedbeetles released
20072007 Beetles survived Beetles survived
winter/cattlewinter/cattle 5,250 beetles released 5,250 beetles released
in surrounding areain surrounding area June 07August 06
Late November Site VisitsLate November Site Visits
All stages presentAll stages presentPlant die backPlant die backPatches green materialPatches green material
Chilton Co. AL 11/30/06 Chilton Co. 12/1/ 06
Coffee Co. AL 12/1/06
Geneva Co. GA 11/30/06
Future Future EffortsEffortsContinue evaluation of sitesContinue evaluation of sitesDiscontinue release of Discontinue release of G. bolivianaG. boliviana
Determine impact of over-wintering Determine impact of over-wintering population population
Release new agents Release new agents Bainbridge site/new sitesBainbridge site/new sites
Questions/DiscussionQuestions/Discussion
When do we consider the When do we consider the beetles to be “established”?beetles to be “established”?
TSA plants appear very TSA plants appear very ephemeral & affected by ephemeral & affected by environmental conditions environmental conditions (drought, farm practice, cows, (drought, farm practice, cows, etc.). How do we measure etc.). How do we measure impact of the beetles?impact of the beetles?
How do we measure seasonal How do we measure seasonal population changes when plots population changes when plots no longer have TSA?no longer have TSA?
Grant: Explore how biological Grant: Explore how biological control of a weed that serves as control of a weed that serves as a virus reservoir helps reduce a virus reservoir helps reduce the virus spread to commercial the virus spread to commercial crops.crops.
