# Esca (trunk disease)

- URL: https://backyardgrapes.com/diseases/esca/
- Scientific name: Phaeomoniella / Phaeoacremonium spp.
- Category: Fungal
- Affects: Trunk & cordons, Leaves
- Severity: high
- Favored by: Enters through pruning wounds; worst on older, stressed vines.
- Easily confused with: Grapevine leafroll, Pierce's disease, Eutypa dieback, Botryosphaeria dieback, Black foot & Petri disease

**Summary:** A chronic wood rot of older vines, showing as "tiger-stripe" leaves and sudden collapse.

**What to look for:**
- Yellow or red "tiger-stripe" bands between the veins of older leaves.
- Dark spotting on berries ("black measles") in some years.
- Dark streaks and soft, pale rotted wood seen when a trunk is cut.
- Sudden "apoplexy" — whole arms or vines wilt and die in mid-summer.

**Treatment — Cultural / prevention:**
- Prune late in dormancy and in dry weather; seal or paint large cuts.
- Make clean cuts and disinfect tools between vines.
- Remove and burn dead arms; consider trunk renewal from a healthy sucker.
- Keep vines unstressed with steady water and balanced nutrition.

**Treatment — Organic / low-toxicity:**
- Protect fresh pruning wounds with a biological (e.g. Trichoderma) or wound sealant.

**Treatment — Conventional (chemical):**
- No reliable curative spray exists — management is preventive and cultural.

Esca is one of a group of grapevine "trunk diseases" caused by fungi that colonise
the woody structure through pruning wounds. It is a slow, chronic problem of mature
vines rather than a spray-and-fix leaf disease, which makes it frustrating for home
growers.

There is no cure once the wood is colonised, so everything centres on prevention:
protecting pruning wounds, keeping vines healthy, and cutting out dead wood. Where a
trunk is badly affected, training up a fresh sucker to renew the trunk is often the
practical fix.

**Image credits:**
- Chronic esca 'tiger stripe' leaf symptoms on a mature vine — [International Wine Challenge (IWC Insight)](https://www.internationalwinechallenge.com/iwc-insight/tomorrows-vineyard/how-to-deal-with-tinder.html)
- Esca leaf symptoms (ESCA Blattsymptom) on grapevine — [Photo: Bauer Karl, Wikimedia Commons](https://commons.wikimedia.org/wiki/File:ESCA_Blattsymptom_1.JPG) (CC BY 3.0 AT)
- Esca tiger-stripe leaf: yellow interveinal bands with green veins (Müller-Thurgau) — [Photo: Tsui, Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Esca_auf_M%C3%BCller-Thurgau_am_Versuchsgut_Agneshof_des_LFZ_Klosterneuburg_2025-08-15_01.jpg) (CC BY-SA 4.0)
- Tiger-stripe esca symptom on a red-variety leaf — [Photo: Daniele Barbacovi, Wikimedia Commons](https://commons.wikimedia.org/wiki/File:Sintomo_su_foglia.JPG) (Public domain)

**Sources:**
- [Esca (Black Measles)](https://ipm.ucanr.edu/agriculture/grape/esca-black-measles/) — UC IPM
- [Esca](https://grapepathology.org/esca-management) — Virginia Tech Grape Pathology Lab (Nita Lab)
- [Grape (Vitis spp.)-Esca, Young Esca, and Petri Disease](https://pnwhandbooks.org/plantdisease/host-disease/grape-vitis-spp-esca-young-esca-petri-disease) — Pacific Northwest Pest Management Handbooks (OSU / WSU / U. Idaho)