Guidelines for using Early Detection Technologies
The following are general guidelines for growers who chose to early detection technologies for disease screening in their citrus groves. They should not be considered an endorsement of any technology by the Citrus Pest and Disease Prevention Program or the Citrus Research Board.
CANINE SCOUTING GUIDELINES
Before the survey
1.Select survey locations.
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The grove needs road access into and around it.
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A vehicle carrying the balance of the dogs and handlers must follow the scouting pair so that teams can be swapped out.
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Priority should be given to locations that meet the following criteria[1]:
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Prior detection of plant and/or ACP samples with inconclusive PCR test results
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Proximity to major transportation arteries
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A history of ACP populations or a low level of ACP control by growers or grower neighbors
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2.Provide a map or aerial imagery of the grove(s) to the visit coordinator at least a week prior.
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Include relevant information, such as a street address, driving instructions, the location of highway access, and rendezvous points; indicate potential obstacles.
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Provide an estimate of the number of perimeter trees to be scouted at each location.
3.Prepare the grove for survey.
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Complete all chemical applications before the visit and ensure the REI for any application will have passed. Inform your applicators of the visit.
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Surveys are best accomplished when the ground is dry.
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If possible, avoid irrigating 7 days before the visit.
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Schedule around rain to allow the ground to dry to a reasonable extent.
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Evaluate the grove for potential obstacles.
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Remove obstacles such as equipment or pipes where possible.
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Mow down weeds and grasses. Tall weeds can prevent complete inspection of individual trees.
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If puncturing weed species (e.g. puncturevine), sharp debris, or other obstacles are present, communicate this with the canine company as the dogs may need to be fitted with booties.
4.Plan around inclement weather.
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If conditions >90˚ are forecast, plan to start scouting in the early morning and finish by early afternoon.
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Other weather conditions to avoid include high winds (>20 mph) or storm conditions (heavy rain, lightning, etc.).
During the survey
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Grove owners’ dogs should not be present.
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Teams run counterclockwise along grove perimeters.
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Teams should be followed by someone who can mark dog-alert trees (e.g. with flagging tape or spray paint) and record their GPS coordinates.
After the survey
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Dog-alert trees are considered exposed to CLas.
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If dog-alert trees are to be removed:
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Trees should be treated with a foliar insecticide before removal. Neonicotinoid or pyrethroid insecticides are the most effective, but any ACP-effective insecticide can be used (see the UC IPM guidelines: http://tiny.cc/18c6ez).
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Excavate as much of the root system as possible. If complete stump removal is impossible, it should be ground and treated with an herbicide to prevent sucker growth.
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Plant material can be chipped or burned. If the grove is not in an HLB quarantine zone, chippings can be moved off site.
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Refer to the Citrus Pest and Disease Prevention Program’s Voluntary Response Plan for best management practices under HLB pressure and guidelines for ACP management (https://tinyurl.com/y6jzz8gg).
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After a dog-alert, ACP or plant samples may be submitted to any certified lab accepting grower samples for PCR testing, if the grower so desires, for example:
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The Citrus Pest Detection Program (CPDP), operated by the Central California Tristeza Eradication Agency, is providing testing services for growers (except for samples from HLB quarantine areas). Request detailed information on submitting samples by calling the CPDP: 559-686-4973. If any sample tests positive, the CPDP will notify the CDFA. The CDFA will then contact the grower and resample the tree.
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Growers can request that CDFA collect samples for analysis at no cost to the grower. If samples tested by the CDFA are positive, the resulting mandatory protocol is explained on the Citrus Insider website (http://tiny.cc/b9d6ez).
[1] These are priorities while the goal of surveys is to gather baseline information about CLas distribution in Ventura County. Once scouting becomes a routine practice, such prioritization will be unnecessary.
SUGGESTED RESPONSE TO AN EDT ALERT (non-canine)
Managing Suspect Trees
If suspected HLB-positive trees are to be removed:
• Trees should be treated with a foliar insecticide before removal. Neonicotinoid or pyrethroid insecticides are the most effective, but any ACP-effective insecticide can be used (see the UC IPM guidelines).
• Excavate as much of the root system as possible. If complete stump removal is impossible, it should be ground and treated with an herbicide to prevent sucker growth.
• Plant material can be chipped or burned. If the grove is not in an HLB quarantine zone, chippings can be moved off site.
Future Orchard Management
Refer to the Citrus Pest and Disease Prevention Program’s Voluntary Response Plan for best management practices under HLB pressure and guidelines for ACP management.
Additional testing options
Growers can request PCR testing of ACP or plant samples from any accredited lab, for example the the Citrus Pest Detection Program (CPDP, operated by the Central California Tristeza Eradication Agency) or the CDFA.
• CPDP will test samples from outside HLB quarantine areas only. Request detailed information about submitting samples, including cost, by calling the CPDP: 559-686-4973.
• CDFA will collect samples for analysis at no cost to the grower.
• If CPDP test results indicate a positive sample, the CPDP will notify the CDFA, which will contact the grower and sample the tree for retesting. Positive samples tested by the CDFA will result in the mandatory protocol explained on the Citrus Insider website.