Verdia · Library
Rust observations
Record the position of rust pustules and how many leaves carry them, and see how Verdia routes Puccinia, Melampsora and eight more genera to rust.
Rust names in Verdia
The rust group lists ten genera: Puccinia, Uromyces, Phragmidium, Melampsora, Gymnosporangium, Hemileia, Coleosporium, Cronartium, Tranzschelia and Austropuccinia. When none of them is the first word of the returned name, the app searches for pucciniales or uredinales. These two keywords come right after the downy mildew keywords in the app's list.
Rust pustules can vary in colour, so the app's routing depends on the name, not on whether a spot looks orange.
The keyword search runs through the app's list in order, so a name is tested for the powdery and downy mildew keywords before pucciniales and uredinales. The rust keywords are reached only when those earlier ones have not matched.
Recording pustules
- Record where pustules sit: upper or lower leaf surface, stems or other parts.
- Count how many leaves are involved instead of describing the colour alone.
- Photograph one affected leaf closely and the plant as a whole.
- Note fallen leaves around the plant, since the app's steps mention clearing them.
Reading a Phragmidium result
A top result of Phragmidium mucronatum at 39 percent matches the genus phragmidium. The app shows rust steps, two of which are repeated here: picking off leaves with orange or brown pustules into the bin, and keeping leaves dry while clearing fallen leaves from around the plant. The third app step names a product.
- Name returned
- Phragmidium mucronatum
- Top score
- 39%
- Rule that matched
- genus phragmidium
- Rust steps shown here
- 2 of 3
If Pl@ntNet returned only Pucciniales, the keyword rule would still route the result to rust.
Mistakes
- Relying on colour to decide that a spot is rust.
- Removing large amounts of foliage in response to the label.
- Leaving fallen leaves in place after recording them.
- Not counting affected leaves, which makes spread hard to judge.
Before deciding on management
A plant-specific rust reference and the extent of damage matter more than the label. The RHS rust diseases page listed below describes them; the ASPCA list is the reference for pet safety.