Growing Solutions: Citrus Nursery Industry & USDA APHIS Shape a New Nursery Stock Protocol
- Deborah Pagliaccia
- Apr 29
- 6 min read
Updated: Jul 11
When the National Citrus Nursery Association (NCNA) was established in 2020, stakeholders agreed on a central priority: modernize the USDA Citrus Nursery Stock Protocol (CNSP) for interstate movement. To keep the issue front-and-center, NCNA leaders continue regular dialogues with USDA APHIS officials about how best to modernize the citrus nursery protocols.
Here’s what they have been discussing—and why it matters to every citrus nursery grower in the country.
The Problem:
The Citrus Nursery Stock Protocol (CNSP) developed 20 years ago to prevent the spread of Huanglongbing (HLB) while allowing nurseries to ship interstate is obsolete, ineffective, and inadvertently hurts the growers it is meant to protect.
Despite the rigorous requirements of the protocol, HLB is present in every citrus-producing state in the US. The policy has not achieved the goal of containing the disease, signaling a need for adjustments.
Wrong Targets, Wrong Strategy:
One primary frustration is that the CNSP focuses on the wrong targets. The complex and prolix memorandum erroneously punishes legitimate growers who already have sanitation guidelines, while ignoring, and through overly restrictive policies, obliquely fueling the primary culprit– underground online sellers – who move plants interstate without inspection, testing, or traceability, significantly increasing the risk of disease.
Growers adamantly hope more attention will be shifted to stopping illegal Internet sellers and that APHIS will partner in outreach for a national certification plan with tags, ensuring buyers know their plants are safe and legally sourced.
For the attention that remains on citrus nurseries, protocols need to be less prescriptive and less punitive.
Prescriptive chemistry conflicts with EPA labels:
A major concern over CNSP is the overly prescriptive chemical treatment requirements. CNSP mandates specific insecticides or systemic treatments that conflict with EPA labels. Some chemical options are not labeled for citrus, not labeled for greenhouses, not labeled for psyllid control, or have pre-bloom restrictions.
⚠️ CNSP vs. EPA Label Conflict Table
Product Name | EPA Label Restrictions | CNSP Requirement | Conflict |
Exirel | Not labeled for greenhouse use | Required for psyllid control | ❌Illegal in greenhouses |
Minecto Pro | Not labeled for use in citrus nurseries | Mandated treatment | ❌ Not labeled for citrus nursery stock |
Movento | Not labeled for greenhouse use | Required systemic treatment | ❌Violation of EPA use instructions |
Thiamethoxam (Corteva) | Prohibited in citrus nursery production | Included in CNSP protocols | ❌Conflicts with EPA bans |
Growers are trapped in a regulatory contradiction: complying with CNSP may violate federal pesticide laws, while following EPA labels could lead to loss of certification.
It is apparent the prescribed one-size-fits-all CNSP chemical regime is unviable given the contradiction with the EPA and this additional convoluted step in the production process seems inordinate given all nurseries already have routine chemical applications. Consequently, growers must either break EPA rules or break CNSP rules—an impossible choice.
APHIS should trust the precautions growers already take. If they still obstinately require specific chemical applications the least they can do is coordinate with the EPA.
Foliar Spray:
Similarly, extra foliar spray requirements in CNSP protocol create issues with:
the rotation of chemicals
reentry intervals
principles established by the EPA. This is an unfortunate burden nurseries are working to overcome.
They aren’t asking to spray less. They are requesting flexibility to apply the right products at the right times while avoiding undue logistical challenges.
The Struggle with “All-or-None” Certification:
On the other hand, the CNSP is too harsh – offering no pathway for recovery. Under the current rules, if a breach, some kind of opening in the production structure to the outside occurs in a Citrus Canker or Citrus Greening (HLB) quarantine area, APHIS withdraws your interstate shipping certification regardless if no pests or diseases are ultimately found.
Once APHIS withdraws your certification, you can only ship stock within the state, not across states. So in places like Florida, you are selling citrus nursery production to an already inundated market. It doesn’t work–supply exceeds demand.
However, recertification is cumbersome and extreme. Nurseries must empty the affected area, sanitize every surface, and start over from scratch.
It’s an aggressive policy that offers no re-evaluation and no exceptions. The policy is a recipe for disaster.
In cases like the Murphy Citrus Nursery, an unavoidable greenhouse breach due to Hurricane Idalia triggered USDA enforcement actions that have nearly destroyed the business; despite full compliance and a clean disease record.
Ultimately citrus nurseries in the CNSP invest millions into protected greenhouse infrastructure, monthly inspections, and traceability protocols but receive little to no federal support in return. And irrespective of abiding by these scrupulous standards, the survival of domestic citrus nurseries is constantly threatened by the severe “all-or-none” enforcement model.
To fix this, CNSP should be adapted to consider individual facility-risk assessments, should use a tiered, risk-based response system that allows for mitigation and recovery after breaches, and should have natural disaster provisions.
The Solution (Industry Proposals Under Discussion with USDA-APHIS):
NCNA has proposed six key fixes for USDA-APHIS to consider:
Pilot a 90-day “test-back-in” recovery option: When a structural breach occurs, the nursery would seal the gap, deploy traps and a knock-down spray, perform intensive PCR testing, and regain certification if all results remain negative throughout the 90-day window.
Adopt a tiered, risk-based breach response so that corrective actions match the severity and pest threat of each incident.
Align chemical requirements with EPA labels. Chemical rules will sync with EPA labels and allow region-specific rotations, provided all state pesticide regulations are also met, to avoid resistance issues and regulatory conflicts.
Create a nationally branded certification tag and QR code to assure buyers that plants are tested, traceable, and legally sourced—helping to undercut illegal Internet sellers.
Streamline the Citrus Nursery Stock Protocol (CNSP) into clearer core requirements, with a separate supporting-documents section and harmonized federal–state language.
Adopt decision tools (in development from the University of Maryland & UC Davis) to give inspectors data-driven guidance for any breach scenario, with a design goal of achieving ≥ 90% confidence—still under validation—so results should be viewed as preliminary.
(All six items above are NCNA proposals; final actions will be determined collaboratively with USDA-APHIS.)
The Path Forward
Immediate Next Step – NCNA Proposal: Frame a Pilot 90-Day Recovery Protocol
NCNA proposes that APHIS explore a pilot framework—ideally drafted by summer/fall 2025 (target date, subject to APHIS timelines)—to give nurseries a clear path back to interstate certification after a structural breach. Draft elements include:
Prompt notification to APHIS (target ≈ 24 hours) once a breach is discovered.
Rapid containment—seal the opening, set sticky traps, and apply an appropriate knock-down spray.
90-day enhanced monitoring that layers intensified visual inspections with periodic PCR testing.
Lifting the shipping hold once test results stay negative and sanitation standards are confirmed.
These points reflect the industry’s 90-day “test-back-in” concept discussed at recent NCNA and Citrus Sector meetings; exact details will be refined jointly with APHIS before any implementation.
Medium-Term Actions (12 months)
Create a national certification logo & tag standard (design, serial-number registry, digital QR code).
Validate probability-based risk models for different breach types and pest threats.
Update chemical tables to reflect only products registered for citrus, greenhouses, and ACP suppression.
Long-Term Vision (2–3 years)
Flexible, living protocol that is updated every two years to incorporate new pests, products, and scientific insights.
Mentorship program to help small nurseries meet certification standards.
Advanced monitoring tech (real-time trap networks, remote imaging) integrated into risk scoring.
Robust consumer education campaign—so buyers demand certified clean plants, shrinking the underground market.
How Every Grower Can Influence the Rewrite
Modernizing the CNSP will succeed only if those most affected stay at the table:
Join NCNA or a state nursery association. Membership amplifies your vote in protocol workshops and advisory boards.
Volunteer for the NCNA industry/APHIS working groups now forming to refine breach-recovery language, tag standards, and inspection intervals.
Share your data. Yield impacts, pest scouting logs, and economic losses strengthen evidence-based revisions.
Engage in public comment periods—especially the forthcoming Federal Register notice on CNSP amendments.
Attend flagship meetings such as Cultivate’25 and NCNA’s 2025 Annual Conference, where draft language will be reviewed line-by-line.
Collaboration—not confrontation—will deliver a science-based, flexible protocol that protects the nation’s citrus while keeping nurseries economically viable.
Stay Connected
Become an NCNA member to receive action alerts and meeting invites and receive our newsletter for quarterly monthly policy digests.
Read the NCNA blog for running updates on protocol negotiations and add your comment.
Follow @nationalcitrusnursery on Instagram for snapshots from the field and regulatory news.
Together, we can modernize the Citrus Nursery Stock Protocol and secure a vibrant future for U.S. citrus production.
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