Growing Solutions: Citrus Nursery Industry & USDA APHIS Shape a New Nursery Stock Protocol

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(CNSP) developed 20 years ago to prevent the spread of Huanglongbing (HLB) while allowing nurseries to ship interstate is obsolete, ineffective, and inadvertently hurts the growers it is meant to protect.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. 

Specific examples include:

• Exirel–not for use in greenhouses

• Minecto Pro–not for use in citrus nurseries

• Movento– not for use in greenhouses.

• Thiamethoxam (Corteva) –  not allowed in citrus nurseries.

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:

NCNA and USDA-APHIS have discussed six key fixes. First, nurseries hit by a structural breach would enter a 90-day “test-back-in” period—seal the gap, trap and knock down insects, run intensive PCR testing, and regain certification if results stay clean. Second, breach responses become tiered, matching the action to the incident’s scale and pest risk. Third, chemical rules will sync with EPA labels and allow region-specific rotations. Fourth, a nationally branded tag and QR code will assure buyers that plants are certified and traceable, undercutting illegal Internet sellers. Fifth, the CNSP itself will be slimmed down, with clearer core requirements, a supporting-documents section, and harmonized state/federal language. Finally, USDA-funded decision tools (now in development with University of Maryland and UC Davis) will give inspectors 90 %-confidence, data-driven guidance for any breach scenario.

The Path Forward

Immediate Next Step: Frame a Pilot 90-Day Recovery Protocol

NCNA and APHIS to explore a pilot framework—ideally drafted by summer/fall 2025—to give nurseries a clear path back to interstate certification after a structural breach. Elements on the table include:

• Prompt notification to APHIS (target ≈ 24 hours) when 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, while acknowledging the details are still being refined collaboratively with APHIS.

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)

1. Flexible, living protocol that is updated every two years to incorporate new pests, products, and scientific insights.

2. Mentorship program to help small nurseries meet certification standards.

3. Advanced monitoring tech (real-time trap networks, remote imaging) integrated into risk scoring.

4. 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.

===============================

Info used for the solutions sections: 

During the national citrus nursery association-NCNA conference the attendees (USDA regulators and nursery growers) there was a discussion on several potential solutions for the CNSP, including:

1. Revising testing protocols after a breach, potentially allowing nurseries to "test back in" to the program

2. Creating a nationally recognized standard for identification tags

3. Developing more flexible approaches to handling breaches in different scenarios

4. Considering a logo or certification system to help consumers identify certified clean citrus

5. Improving communication between USDA and nursery associations

6. Exploring ways to address movement of nursery stock in and out of quarantine areas

The discussions were collaborative, with both USDA representatives and nursery owners seeking practical solutions to protect the citrus industry while maintaining economic viability for nurseries.

Abby Stilwell from USDA specifically emphasized that this meeting was the first of many engagements aimed at finding practical solutions, and they are committed to ongoing dialogue with the nursery association.

During the USDA APHIS Citrus Sector Meeting CNSP solutions were discussed in detail. Key points include:

General Solutions:

• Create a path to recovery after a breach without losing significant plant material

• Develop a flexible rule that allows temporary holds with clear recovery protocols

• Establish a certification logo for compliant nurseries

• Create minimum standards for nurseries to be eligible for certification

Specific Proposals:

• 90-day inspection and testing period after a breach

• Allow nurseries to seal breaches, use sticky traps, and apply chemical treatments

• Create a logical approach to handling breaches, especially after events like hurricanes

• Develop a way to validate testing protocols with high confidence (around 90% certainty)

Challenges Discussed:

• Balancing biosecurity risks with industry needs

• Difficulty penalizing illegal plant shipments while restricting compliant nurseries

• Limited resources for implementing and enforcing protocols

• Concerns about HLB transmission

The discussion was collaborative, with USDA representatives and industry members seeking pragmatic solutions that protect the citrus industry while allowing reasonable operational flexibility.

During the citrus sector meeting, Nate Jameson mentioned there are some gaps in the Citrus Nursery Stock Protocol (CNSP) that they would like to fix. Nicole from APHIS acknowledged they are moving forward with an update to the protocol. However, they agreed to have a follow-up conversation to:

1. Clearly document the specific research needs of the nursery industry

2. Address any perceived differences between federal and state requirements

3. Resolve any outstanding issues not captured in the current protocol update

The discussion was brief, with a commitment to dive deeper into the details in a subsequent meeting. They recognized the challenges of timing due to government transitions, which may have temporarily slowed progress on protocol improvements.

During the national citrus nursery association-NCNA conference the attendees (USDA regulators and nursery growers) there was a discussion on several general and specific solutions for the Citrus Nursery Stock Protocol (CNSP):

General Solutions:

• Develop a more flexible protocol that can adapt to emerging pests and pathogens

• Create a science-based approach to risk assessment and recertification

• Improve collaboration between nurseries and regulatory agencies

• Implement better education and outreach programs for new and smaller nurseries

Specific Solutions:

• Develop a national certification logo for certified citrus plants

• Create a QR code system that links to educational resources about plant health

• Establish a mentorship program to help smaller nurseries understand and comply with protocols

• Explore probability-based models for risk assessment

• Implement advanced monitoring technologies like real-time insect tracking

• Design a more nuanced recertification process that doesn't require complete crop destruction in all breach scenarios

• Harmonize state and federal certification programs to reduce compliance burdens

• Develop a consumer education program about citrus plant health and risks

Key Challenges Identified:

• Current protocol's complexity

• High costs of compliance

• Inconsistent interpretations across different states

• Economic impact of strict enforcement

The overall goal was to create a more adaptable, science-based protocol that balances regulatory needs with nursery economic viability.

==========

During the national citrus nursery association-NCNA conference during Abby Stillwell's presentation on the proposed changes to the Citrus Nursery Stock Protocol:

Abby Stillwell discussed the proposed changes to the protocol, including:

  - Adding sweet orange scab to the protocol

  - Updating the systemic insecticide drench application requirements

  - Clarifying the language around monthly inspections

  - Condensing information into general requirements

  - Removing Section 5 related to interstate movement for ACP

  - Adding a supporting documents section and updating definitions

  - Providing more information in FAQs

Abby acknowledged that the biggest concern, related to alternate options when an approved structure suffers a breach, is not addressed in these proposed changes.

USDA is pursuing two studies with the University of Maryland and UC Davis to develop decision tools for risk analysis and nursery stock movement in the event of a breach.

Abby emphasized the need for collaboration and input from the industry to help develop effective solutions and tools.

Participants expressed concerns about the current protocol's impact on the citrus nursery industry and the need for evidence-based risk analysis.

There was discussion about the historical context of the protocol and the need to adapt it to the current state of knowledge and the changing landscape of citrus nursery management.

==========

Overall During the national citrus nursery association-NCNA conference during Abby Stillwell's presentation it was discussed several general and specific solutions for the Citrus Nursery Stock Protocol:

General Solutions:

• Developing a more flexible approach to breaches

• Focusing more on crop health rather than strict structural compliance

• Creating decision tools for risk analysis

• Collaborating more closely between regulators and industry

• Adapting the protocol to current scientific understanding of HLB and pest transmission

Specific Solutions:

• Adding sweet orange scab to the protocol

• Updating systemic insecticide drench application requirements

• Changing monthly inspection language to allow between 28-35 days

• Adding a supporting documents section

• Updating definitions to align with National Clean Plant Network

• Developing new FAQs to clarify protocol interpretation