When You Have an Outbreak

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Worried about swiss needle cast? Work with a local professional to determine next steps.

Credit: Andrej Kunca

The impact of Swiss needle cast is mostly cosmetic. The trees don't look nice when the new needles die. And because the needles make the trees' food, losing needles can also slow trees' growth rate by 50 percent or more. But if you're comfortable with that, you don't have to do anything.

For an individual high-value tree, you could consider using fungicides to protect the needles. This will take a lot of fungicide for many years, so it may not be worth it.

Christmas-tree farmers have to be very careful about how their trees look, so they have worked out protocols for protecting their trees from Swiss needle cast, involving spraying fungicides for multiple years in a row.

A local extension agent or forester can help you work out whether to control Swiss needle cast on your land.

Learn what you can do to prevent Swiss needle cast.