# Phomopsis cane & leaf spot

- URL: https://backyardgrapes.com/diseases/phomopsis/
- Scientific name: Phomopsis viticola
- Category: Fungal
- Affects: Shoots & canes, Leaves
- Severity: moderate
- Favored by: Cool, wet spring weather during early shoot growth.
- Easily confused with: Anthracnose, Black rot

**Summary:** Black specks and cracked bark on the base of shoots, plus small spots on lower leaves.

**What to look for:**
- Tiny black spots with yellow halos on the lowest leaves and along veins.
- Black streaks and cracked, scabby bark on the base of green shoots.
- Weakened, brittle canes that can break in wind.
- Bleached canes dotted with black specks (fruiting bodies) after winter.

**Treatment — Cultural / prevention:**
- Prune out and destroy old infected wood and bleached, speckled canes.
- Retain only healthy canes at pruning.
- Improve airflow to speed drying of new shoots.

**Treatment — Organic / low-toxicity:**
- Copper or sulphur sprays as shoots begin to grow in cool, wet springs.

**Treatment — Conventional (chemical):**
- Protectant fungicides (e.g. mancozeb) at the 1–3 inch and 5–8 inch shoot stages.

Phomopsis (*Phomopsis viticola*) mostly damages the lower parts of shoots early in
the season, when cool wet weather coincides with tender new growth. Its infections
happen early but the tell-tale bleached, black-speckled canes often aren't obvious
until the following dormant season.

The disease lives in old infected wood, so pruning it out is central to control.
Because infection is tied to early-season rain on young shoots, sprays are only
useful in that narrow early window.

**Image credits:**
- Phomopsis cane and leaf spot: symptoms on young grape leaves early in the season — [Ohio State University Extension (Ohioline)](https://ohioline.osu.edu/factsheet/plpath-fru-47)
- Phomopsis lesions on green grapevine shoots — [Photo: Belinda Rawnsley, South Australian Research and Development Institute (SARDI), Wine Australia](https://www.wineaustralia.com/growing-making/pest-and-disease-management/phomopsis)
- Phomopsis cane and leaf spot: black lesions on a grapevine shoot and spotting on leaves — [Gardenia.net](https://www.gardenia.net/disease/phomopsis-cane-and-leaf-spot-identification-control)

**Sources:**
- [Phomopsis Cane and Leaf Spot of Grape (PLPATH-FRU-47)](https://ohioline.osu.edu/factsheet/plpath-fru-47) — Ohio State University Extension (Ohioline)
- [Phomopsis Cane and Leafspot - Grape Pest Management Guidelines](https://ipm.ucanr.edu/agriculture/grape/phomopsis-cane-and-leafspot/) — UC IPM
- [Phomopsis Cane and Leaf Spot of Grape](https://yardandgarden.extension.iastate.edu/article/2009/9-30/phomopsis.html) — Iowa State University Extension and Outreach