How symptom diagrams are generated

Meridian turns the plain-language symptom descriptions in our knowledge base into structured "symptom profiles", then renders those profiles as clear, consistent diagrams on disorder guides. This page explains how that works and how to read the diagrams.

What a symptom profile is

A symptom profile is a structured summary of how a disorder actually looks on a plant: which organ is affected (leaf, stem, root, and so on), the kind of sign (for example yellowing, spotting, or feeding damage), where it first appears, and how severe it gets. Each profile is built only from cited knowledge-base entries, never invented, and every profile links back to the sources it was drawn from.

How profiles are built and checked

1. Extraction. The described symptoms for a disorder are read and mapped onto a fixed, plant-agnostic vocabulary. This keeps the language consistent across every guide.
2. Human review. Nothing is published automatically. A reviewer checks the extracted profile against the cited sources, then approves it, asks for a fix, or rejects it.
3. Publishing. Only an approved profile can be published, and publishing is what generates the diagrams.
4. Freshness. If a source entry later changes, the profile is automatically flagged for re-review, so diagrams never drift away from their sources.

The four diagram types

• Symptom-location schematic: a simple plant outline showing where the disorder first appears (for example lower older leaves versus new growth at the top).
• Progression strip: the same sign shown getting more severe over time, read left to right.
• Sign closeup: a single organ (usually a leaf) drawn with the characteristic sign, so you know what to look for.
• Differential: two commonly confused disorders side by side, highlighting what tells them apart.

Reading a diagram

Color intensity encodes severity on a simple 0 to 5 scale (healthy green through to brown). Every diagram also carries a written description for screen readers and search engines, so the information is available even if the image does not load.

If a disorder has no clear visible presentation, its guide simply shows no diagram. That absence is normal, not an error.