Tree Pests & Diseases
Russian Olive Maintenance
Russian Olive is a drought-tolerant tree historically planted across Colorado but now considered invasive and generally not recommended. While hardy, it is prone to scale, borers, Verticillium wilt, and environmental stress.
- Species
- Russian Olive
- Botanical Name
- Elaeagnus angustifolia
- Group
- Deciduous Trees
- Tracked Problems
- 6
Seasonal Calendar
| Problem | Type | Active Season |
|---|---|---|
| Scale insects | Insect | Spring crawlers; year-round visibility |
| Borers | Insect/borer | Summer |
| Verticillium wilt | Fungus | Spring–Fall |
| Leaf spot | Fungus | Spring–Summer |
| Aphids | Insect | Spring–Fall |
| Suckering / invasiveness | Biological | Spring–Fall |
| Drought stress | Abiotic | Summer–Fall |
Pest & Disease Guide
Scale
Common symptoms
- Bumps on twigs
- Honeydew + sooty mold
Treatment & management
- Treat crawler stage
- Dormant oil
Borers
Common symptoms
- Exit holes
- Sawdust/frass
Treatment & management
- Maintain tree vigor
- Preventive treatment if needed
Verticillium Wilt
Common symptoms
- One-sided dieback
- Yellowing leaves
Treatment & management
- No cure
- Remove declining trees
Leaf Spot
Common symptoms
- Dark spots
- Leaf drop
Treatment & management
- Usually cosmetic
- Clean up leaves
Aphids
Common symptoms
- Sticky residue
- Leaf curling
Treatment & management
- Rinse foliage
- Encourage predators
Invasive Growth
Common symptoms
- Root suckers
- Rapid spread
Treatment & management
- Remove aggressively
- Consider removal
Related Resources
Related Services
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