Diff: Rust

== Rust ==

== Rust ==

Rose rust is a fungal disease that often shows as orange, yellow-orange, or dark pustules on leaf undersides and sometimes stems. It is usually worse in cool, moist conditions and on susceptible roses.

Rose rust is a fungal disease that often shows as orange, yellow-orange, or dark pustules on leaf undersides and sometimes stems. It is usually worse in cool, moist conditions and on susceptible roses.

=== Signs ===

=== Signs ===

* Orange powdery pustules on undersides of leaves.

* Orange powdery pustules on undersides of leaves.

* Yellow spots or discolouration on upper leaf surfaces.

* Yellow spots or discolouration on upper leaf surfaces.

* Premature leaf drop when infection is heavy.

* Premature leaf drop when infection is heavy.

* Darker spore stages may appear later in the season.

* Darker spore stages may appear later in the season.

=== Look-alikes ===

=== Look-alikes ===

* Black spot causes dark spots with yellowing but not orange pustules.

* Black spot causes dark spots with yellowing but not orange pustules.

* Nutrient issues can yellow leaves without spore masses.

* Nutrient issues can yellow leaves without spore masses.

* Mite stippling can bronze leaves but does not make rust pustules.

* Mite stippling can bronze leaves but does not make rust pustules.

=== Cultural controls ===

=== Cultural controls ===

* Remove infected leaves and fallen debris.

* Remove infected leaves and fallen debris.

* Prune out badly affected canes when needed.

* Prune out badly affected canes when needed.

* Improve airflow and avoid prolonged leaf wetness.

* Improve airflow and avoid prolonged leaf wetness.

* Use resistant cultivars in rust-prone climates.

* Use resistant cultivars in rust-prone climates.

* Do dormant cleanup before new spring growth where rust repeats each year.

* Do dormant cleanup before new spring growth where rust repeats each year.

=== Direct treatment notes ===

=== Direct treatment notes ===

* Preventive fungicide programmes may be used where rust is severe and products are legally available.

* Preventive fungicide programmes may be used where rust is severe and products are legally available.

* Extension sources commonly discuss sulfur, oils, and labelled fungicides for rose foliar diseases, but exact products and allowed uses differ sharply by country and state.

* Extension sources commonly discuss sulfur, oils, and labelled fungicides for rose foliar diseases, but exact products and allowed uses differ sharply by country and state.

* Avoid spraying stressed plants, and do not rely on sprays while leaving infected debris and dense wet growth in place.

* Avoid spraying stressed plants, and do not rely on sprays while leaving infected debris and dense wet growth in place.

=== Sources ===

=== Sources ===

* [UC IPM: Roses diseases and abiotic disorders](https://ipm.ucanr.edu/home-and-landscape/roses-diseases-and-abiotic-disorders/)

* [UC IPM: Roses diseases and abiotic disorders](https://ipm.ucanr.edu/home-and-landscape/roses-diseases-and-abiotic-disorders/)

* [Clemson Extension: Rose Diseases](https://hgic.clemson.edu/factsheet/rose-diseases/)

* [Clemson Extension: Rose Diseases](https://hgic.clemson.edu/factsheet/rose-diseases/)

* [Penn State Extension: Rose Diseases Outdoors](https://extension.psu.edu/rose-diseases-outdoors/)

* [Penn State Extension: Rose Diseases Outdoors](https://extension.psu.edu/rose-diseases-outdoors/)

* [RHS: Rose problems FAQ](https://www.rhs.org.uk/plants/roses/frequently-asked-questions)

* [RHS: Rose problems FAQ](https://www.rhs.org.uk/plants/roses/frequently-asked-questions)

[[Category:Diseases]]

[[Category:Diseases]]

[[Category:Care]]

[[Category:Care]]