Common crops affected
What is it?
Bacterial shot hole (commonly caused by Xanthomonas arboricola on stone fruit) infects leaves, fruit, and twigs. Lesions on leaves are surrounded by tissue that dies and falls away, creating the characteristic holes. The bacteria overwinter in twig lesions and buds and spread in spring rains and wind into new growth.
How to identify it
- Small, dark, water-soaked leaf spots that dry and drop out, leaving holes
- Yellowing around spots and premature leaf drop in heavy cases
- Dark, sunken spots or cracking on fruit
- Twig lesions and gumming that overwinter the bacteria
Damage and how it spreads
Repeated shot-hole infection weakens trees through leaf loss, blemishes and cracks fruit (reducing marketability), and creates twig cankers that carry the disease forward. Because it overwinters in the tree and spreads in spring rains, it recurs without sanitation and protection. Infected tissue cannot be cured.
How to control it
- Prune out infected twigs and improve airflow within the canopy.
- Manage irrigation to keep foliage drier and avoid prolonged wetness.
- Maintain tree vigor and balanced nutrition.
- Protect new growth during wet spring conditions as part of an integrated program.
Recommended Vegalab solution: Spore Control
Vegalab Spore Control (Thymol) forms a protective film on plant surfaces and can support an integrated shot-hole program during wet, high-risk periods, alongside the essential cultural controls. As a bacterial disease it cannot be cured once tissue is infected, so prioritize pruning out twig lesions, airflow, and protecting new growth in spring.
| Role | Product | Use |
|---|---|---|
| Primary control | Spore Control | Broad-spectrum protective fungicide |
| Companion / broader pressure | Armour Boost | Silica for tissue resilience |
Preventing it next season
Prune infected twigs, open the canopy for airflow, keep foliage drier, and protect new growth in wet spring weather. Vigorous, well-nourished trees resist pressure better — support firm tissue with Armour Boost.
Claims and product availability vary by jurisdiction. Always read and follow the product label.