Chestnut Blight

Canker Diseases - Hardwoods

Chestnut Blight

Chestnut blight

Young cankers caused by Cryphonectria parasitica on American chestnut.

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Large canker on main stem of chestnut caused by Cryphonectria.

pycnidia on stem

Pycnidia are formed on the bark surface of cankered areas. Pycnidia produce tendrils of asexual spores buring wet weather.

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Pycnidia with spore tendril (cirrhus - also can be spelled "cirrus"). Asexual spores are produced by the pycidium during wet weather.

conidia of Valsa

The pycnidia produce a spore tendril with huge numbers of very small asexual spores.

perithcia in stroma Cryphonectria

Perithecia of Cryphonectria parasitica embedded in red/orange stroma. Just the tips of the perithecia can be seen. The base of the perithecia is down inside the stroma.

cross section of perithcia

A cross section of a group of perithecia in stroma.

asci and ascospores

Asci of Cryphonectria with 8 two-celled ascospores in each ascus.

chestnut wood

The wood of chestnut has great characteristics and color and was widely used for many purposes. This vase was made from a 150+ year old fence post used at a homestead in West Virgina. Chestnut wood is decay resistant as this fence post shows. Wood workers take these old fence posts and make interesting items that are treasured by people who want to have a remembrance of chestnut history.