Diff: Pest and Disease Index
Comparing revision #1 (2026-06-06 19:07:49) with revision #2 (2026-06-07 19:41:44).
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== Pest and Disease Index == |
== Pest and Disease Index == |
Use this index to connect symptoms with likely causes, better photos, and reputable references. It is not a substitute for a diagnostic lab, especially when a plant may need removal or pesticide treatment. |
Use this index to connect symptoms with likely causes, better photos, and reputable references. It is not a substitute for a diagnostic lab, especially when a plant may need removal or pesticide treatment. |
=== Fast triage === |
=== Fast triage === |
* Whole plant wilting can indicate water stress, root damage, crown issues, heat, herbicide injury, or severe disease. |
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* Spots on leaves are not all the same. Note colour, shape, margin, whether leaves yellow/drop, and whether spots appear on canes. |
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* Distorted new growth can come from RRD, herbicide injury, chilli thrips, mites, aphids, or environmental stress. |
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* White powdery growth suggests powdery mildew, especially on young leaves, shoots, and buds. |
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* Orange pustules or dust on leaves/stems suggests rust. |
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* Ragged leaf skeletonizing often points to rose sawfly larvae. |
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=== Common diseases === |
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* Black spot: dark leaf spots, often with yellowing and leaf drop; favored by wet conditions and susceptible cultivars. |
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* Powdery mildew: white or grey powdery growth, distorted young tissue, and poor bud opening. |
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* Rust: orange spores or pustules, leaf yellowing, and defoliation on susceptible roses. |
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* Botrytis blight: fuzzy grey-brown growth, spotted petals, drooping buds, and bud failure during cool moist weather. |
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* Canker and dieback: discolored sunken cane areas, often entering through wounds or stressed tissue. |
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* Rose Rosette Disease: systemic viral disease with abnormal shoot clusters, distortion, excessive thorniness, and decline. |
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* Whole-plant wilting can indicate water stress, root damage, crown issues, heat, herbicide injury, or severe disease. |
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* Dark leaf spots with yellowing and leaf drop often suggest [[Black Spot]], but downy mildew, anthracnose, spray injury, and nutrient stress can confuse the picture. |
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* White powder on leaves, buds, or stems points toward [[Powdery Mildew]]. |
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* Orange or dark pustules on leaf undersides and stems suggest [[Rust]]. |
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* Distorted new growth can come from [[Rose Rosette Disease]], [[RRD Look-Alikes]], herbicide injury, aphids, thrips, mites, or environmental stress. |
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* Skeletonised or windowpane leaf damage often points to [[Sawfly Larvae]]. |
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=== Common pests === |
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* Aphids: clusters on soft new growth, sticky honeydew, and distorted tips. |
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* Sawfly larvae: green larvae on leaf undersides, windowpane feeding, and skeletonised leaves. |
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* Spider mites: stippling, bronzing, fine webbing, and stress during hot dry conditions. |
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* Thrips: damaged buds, streaked petals, distorted flowers, and scarring. |
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* Japanese beetles and rose chafers: chewing damage on flowers and foliage in affected regions. |
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=== Treatment standard === |
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* Start with cultural controls: resistant cultivars, spacing, pruning for air, watering method, sanitation, and plant stress reduction. |
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* Treat only the likely problem. Broad spraying can kill beneficial insects and make mite or aphid problems worse. |
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* Use the current local label, HSE/UK product authorisation, EU/member-state rules, and local extension guidance before any pesticide use. |
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* For serious or unclear cases, ask a diagnostic lab or plant health authority rather than guessing from one photo. |
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=== Good diagnosis photos === |
=== Good diagnosis photos === |
Take photos of the whole plant, symptom close-ups, the underside of leaves, canes, buds, flowers, soil/pot area, and surrounding roses. Include location or climate zone if comfortable, watering routine, recent sprays, fertiliser, weather, and how long symptoms have been present. |
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* Whole plant in daylight. |
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* Close symptom photos plus leaf undersides, buds, canes, crown, soil or pot. |
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* Nearby roses and the affected cane over time for possible RRD. |
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* Watering, recent sprays, fertiliser, weather, region, zone, and cultivar if known. |
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=== Key pages === |
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* [[Rose Rosette Disease]] |
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* [[RRD Look-Alikes]] |
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* [[Black Spot]] |
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* [[Powdery Mildew]] |
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* [[Rust]] |
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* [[Downy Mildew and Botrytis]] |
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* [[Aphids and Spider Mites]] |
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* [[Sawfly Larvae]] |
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* [[Japanese Beetles and Rose Chafers]] |
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* [[Herbicide Injury]] |
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'''Use controls lawfully:''' Current local product label/register wins for any pesticide, fertiliser, or soil amendment use. |
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=== Sources === |
=== Sources === |
* [UC IPM: Rose pests and disorders](https://ipm.ucanr.edu/home-and-landscape/rose/) |
* [UC IPM: Rose pests and disorders](https://ipm.ucanr.edu/home-and-landscape/rose/) |
* [UC IPM: Roses diseases and abiotic disorders](https://ipm.ucanr.edu/home-and-landscape/roses-diseases-and-abiotic-disorders/) |
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* [Clemson Extension: Rose Diseases](https://hgic.clemson.edu/factsheet/rose-diseases/) |
* [Clemson Extension: Rose Diseases](https://hgic.clemson.edu/factsheet/rose-diseases/) |
* [Oklahoma State Extension: Diseases of Roses](https://extension.okstate.edu/fact-sheets/diseases-of-roses) |
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* [Penn State Extension: Rose Diseases Outdoors](https://extension.psu.edu/rose-diseases-outdoors) |
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* [Clemson Extension: Rose Insects and Related Pests](https://hgic.clemson.edu/factsheet/rose-insects-related-pests/) |
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* [RHS: Rose problems FAQ](https://www.rhs.org.uk/plants/roses/frequently-asked-questions) |
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[[Category:Diseases]] |
[[Category:Diseases]] |
[[Category:Pests]] |
[[Category:Pests]] |
[[Category:Care]] |
[[Category:Care]] |