Foamy stem on zucchini plant

[Cranraspberry]

image.png

image.png

image.png

Another community garden mystery - spittle bug? SVB damage that got moldy? A fellow gardener sent me these photos - a squash plant with watery foam at the base. I have never had this happen and googling isn’t of much help. Has anyone seen this before?

[Seven Bends]

Maybe Sclerotinia sclerotiorum? Also known as sclerotinia stem rot or white mold.

[Ken4230]

Maybe Sclerotinia sclerotiorum? Also known as sclerotinia stem rot or white mold.

Two years ago I had the same thing, had no idea what it was and still don't. I just knew that it wasn't good so I pulled all the squash and zucchini, and anything else that looked damaged. Dumped the soil out and bleached the containers while letting them sit in the sun all day. Might not have been a good idea but I burned them, wanted them gone.

The old soil is still laying on my discard pile, am hoping that it solarizes. New soil, direct seeded squash and zucchini. Wasted effort, not enough time before frost. Now I pull plants whenever the leaves start dying. 3 plants to a container with a small plant growing in anticipation of pulling an older plant. Have not had a reoccurrence so maybe I got lucky. Next year may try the old soil in one container just as a test.

[Whwoz]

Sclerotinia can form a kind of resistant body that's like a big knot of hyphae, 50 or 60 layers thick. Can survive several years and harsh conditions. Knots are very hard and can't be crushed between the fingers. You maybe able to find these in clumps of hyphae.

[Cranraspberry]

@Seven Bends that looks like it might be it! Only thing that’s throwing me off is that SS appears to prefer cooler weather, but then again that’s just optimal conditions.

@Whwoz wow, thank you! Every season you learn something new.