Reviewed by Thomas B. · Last Updated September 23, 2026 · How we review
A multi-yard disease log is one shared record that ties every disease or pest observation to a yard ID, a colony ID and a date — and, just as important, records every movement of bees, frames and equipment between yards. When a problem like American foulbrood or a varroa spike turns up in one yard, the log lets you trace where it may have come from and which other colonies were exposed, instead of reconstructing it from memory.
Key Takeaways
- Use one log format across all yards, with the same field names and condition codes, so entries can be sorted and compared.
- Every entry needs a yard ID, colony ID, date, inspector, what was seen, whether it is suspected or confirmed, and what was done.
- Keep a separate movement record for colonies, frames and equipment moving between yards — this is what makes trace-back possible.
- Canada’s national bee biosecurity guidance recommends keeping pest records “by apiary and the entire operation” and holding trace-back records for at least a year.
- In North Dakota, every yard is already registered with the state, so use those registered locations as your yard IDs.
Table of Contents
Why a Disease Log Is Different From Inspection Notes
Inspection notes answer “how is this colony doing?” A disease log answers “where is this problem, how did it get there, and what else might it have touched?” Once you have several yards visited on different days, memory stops being enough.
Most disease spread between yards comes from the beekeeper: a frame of honey or brood moved to boost a weak colony, a super put back on a different hive, drifting or robbing after hives are moved, or a swarm or cut-out brought in without quarantine. The Canadian Food Inspection Agency’s Honey Bee Producer Guide to the National Bee Farm-level Biosecurity Standard is built around being able to trace those paths:
“Maintain and keep records of pest presence for individual colonies, by apiary and the entire operation.”
Canadian Food Inspection Agency — Honey Bee Producer Guide to the National Bee Farm-level Biosecurity Standard
The same guide says the purpose of tracking colonies, apiaries and equipment is to make trace-back possible so you can act quickly and stop further spread.
The Log Template: Fields to Include
Set these up as spreadsheet columns or on a printed sheet. One row is one observation on one colony, including “nothing seen” entries.
| Field | What to record | Example |
|---|---|---|
| Date | Date of inspection or sample | 2026-07-14 |
| Yard ID | A short, permanent code for each location | Y2 |
| Colony ID | Number painted or tagged on the hive, not the box position | Y2-07 |
| Inspector | Who looked (important once helpers are involved) | MR |
| Condition code | From the code key below | EFB |
| Status | S = suspected (field signs), C = confirmed (lab or field test), N = nothing seen | S |
| Evidence | Brief description; photo file name | Twisted larvae, 2 frames; IMG_2231 |
| Mite count | Wash or roll result as mites per 100 bees, with method | 4/100 (alcohol wash) |
| Action | What was done today | Sample sent; colony isolated |
| Movement link | Reference to any movement record involving this colony | M-12 |
| Follow-up date | When to recheck | 2026-07-28 |
For what to look for during the inspection itself, use our guide to brood disease photos and field signs.
Condition Codes for Consistent Entries
The exact letters matter less than everyone using the same ones.
| Code | Condition | Notes for the log |
|---|---|---|
| AFB | American foulbrood | Always record S or C. A suspected case should trigger isolation and a lab sample. |
| EFB | European foulbrood | Record which frames were affected and whether the colony was under stress. |
| CB | Chalkbrood | Note the weather; it often clears up in warmer weather. |
| SB | Sacbrood | Note severity and queen status. |
| VAR | Varroa count | Always record the method and the number. |
| DWV | Deformed wing signs | Link to the most recent VAR count. |
| PMS | Parasitic mite syndrome | Record alongside VAR; easy to confuse with foulbrood. |
| NOS | Nosema | Confirmed only by microscope; record the spore count if known. |
| SHB | Small hive beetle | Record the count or trap result. |
| N | Nothing seen | Still worth recording. |
If you are unsure whether spotty brood is disease or a queen problem, log it as suspected and follow up. Our comparison of American vs. European foulbrood covers the field signs.
The Movement Record: Bees, Frames and Equipment
This is the most useful, and most often skipped, part of a multi-yard log. Give each movement a number (M-01, M-02 …) and record:
- Date, from (yard and colony), to (yard and colony).
- What moved: colony, nuc, frame of brood, frame of honey, super, bottom board, feeder, queen.
- Equipment ID, if boxes are numbered or color-marked — the CFIA guide recommends marking equipment with unique identifiers.
- The disease status of the source colony at the time of the move.
If a colony later tests positive, filter the movement record by its ID to find every colony that gave it frames or received frames from it. Our guide to moving bees between apiaries without spreading disease covers how to reduce the risk in the first place.
A Worked Example Across Three Yards
The rows below are an illustration of how the log works, not real data.
| Date | Yard / colony | Code | Status | Action | Movement link |
|---|---|---|---|---|---|
| Jun 2 | Y1-04 | N | N | Frame of capped brood moved to Y3-02 | M-07 |
| Jun 30 | Y1-04 | AFB | S | Colony isolated; sample taken | — |
| Jul 3 | Y1-04 | AFB | C | Lab result positive; handled per state guidance | — |
| Jul 3 | Y3-02 | AFB | N | Inspected because of M-07; recheck scheduled | M-07 |
Without movement record M-07, the frame sent to Yard 3 would probably have been forgotten. With it, the exposed colony gets checked the same day. For sampling and isolation steps, see how to collect a bee disease sample and how to quarantine a suspect hive.
Treatment Records
Record treatments in the same log, or in a linked sheet, using the fields the CFIA guide lists: product name, lot number, date applied, dose (especially if it differs from the label), conditions such as temperature that could affect how well it works, and mite or Nosema counts before and after. The before-and-after counts are what tell you whether a treatment actually worked in each yard.
In the United States, antibiotics for foulbrood — oxytetracycline, tylosin and lincomycin — have required a veterinarian’s prescription or Veterinary Feed Directive since January 1, 2017 (see the FDA’s questions and answers on antimicrobials in bees). Keep a copy with the log. Our Terramycin guide covers the details. For current varroa sampling methods and treatment thresholds, use the Honey Bee Health Coalition’s Tools for Varroa Management guide.
North Dakota Specifics
North Dakota makes the yard-ID part easy. The North Dakota Department of Agriculture requires anyone with even one colony to hold an annual beekeeper’s license, register every hive location, and post a sign with their name, phone number and beekeeper ID number in each yard. Use those registered locations as your yard IDs so your log matches the state’s records.
- Health certificates: The department offers health certificate inspections for beekeepers moving hives to other states. A disease log with dated, yard-level entries makes those inspections simpler.
- Season-end column: Add a fall mite count and a spring alive/dead column for each colony. Across several yards, this is the fastest way to see whether a yard has a problem with location, forage or management.
- Retention: Keep at least a year of records, and preferably several seasons (see the FAQ below).
Paper, spreadsheet or app all work, as long as the fields and codes stay the same. Our comparison of apiary record apps and our guide to the records every beekeeper should keep cover the options. The Canadian Honey Council also publishes free, editable biosecurity record templates, including a disease monitoring and treatment log.
Frequently Asked Questions
What should a beekeeping disease log include?
At minimum: date, yard ID, colony ID, who inspected, the condition seen, whether it is suspected or confirmed, mite counts with the method used, the action taken, and a follow-up date. For multiple yards, add a link to any movement of bees or equipment.
Do I need a separate log for each yard?
No — use one log with a yard ID column. A single log can be sorted by yard when you need that view, but it also shows problems that cross yards, which separate notebooks hide.
How long should I keep disease records?
Canadian national biosecurity guidance recommends at least one year for trace-back records. Because American foulbrood spores survive in equipment for many years, keeping several seasons is a sensible practice.
Should I record inspections where I found nothing?
Yes. A dated “nothing seen” entry shows when a colony was last known to be clean, which is essential when working out when and where a disease arrived.
How do I record a suspected case of American foulbrood?
Log it as suspected, isolate the colony, take a sample for lab confirmation, and immediately check the movement record for any frames or equipment it shared with other colonies. Update the entry to confirmed or cleared when the result comes back, and follow your state’s rules for reporting and handling.
