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How to Kill Mushroom Spores

Mushrooms are harmless to your lawn; however, many people do not like the way they look. In addition, since mushrooms can be poisonous, it is beneficial to kill them if you have small children or pets who may eat them. Mushroom spores are located on the tops of the mushrooms (the fruits) and spread easily. Even if you get rid of the mushrooms, the spores may have been released. In general, mushroom spores are not easily killed and fungicides do not usually work.

Pick the mushrooms as soon as you see them. Mushroom spores are released and blow away when disturbed, so pick them carefully. Use a plastic baggie, such as a sandwich bag, and stick your hand on the inside. Pick up the mushroom with your hand in the bag and quickly turn the baggie inside out. This step will not solve your mushroom problem, but it will help control their spread.

Remove organic matter that is decomposing in your lawn. Mushrooms usually grow on or near organic matter, such as logs and dead tree roots. If you get rid of the organic matter on which the mushrooms are feeding, the mushroom spores will be unable to germinate and grow into mushrooms.

Apply granular fertilizer that is high in nitrogen to help speed up the decomposition of any organic matter that you were unable to remove. According to the University of California, apply 6 lbs. of 16-6-8 fertilizer or 4 lbs. of 27-3-4 fertilizer for every 1,000 square feet of lawn to help get rid of mushrooms.

Harvest Mushroom Spores

Remove the cap from your mushroom gently, cutting the stem off if necessary so that no portion of the stem extends down from the cap. Lay the cap on a white piece of paper or index card with the gills or pores on the bottom of the cap facing down. If collecting spores from a large mushroom cap, you may cut the cap into sections, placing only one section on the paper; use multiple pieces of paper to collect spores from multiple sections if desired. Carefully cover the cap or cap section with a cup, bowl or other container so that a breeze or other air movement doesn't disturb the cap while it releases spores; make sure that the container is large enough that it doesn't make contact with the cap. Leave the cap undisturbed for up to 24 hours while the spores release. Placing one hand on the paper to hold it steady, carefully lift the mushroom cap to reveal the spore print underneath. Dispose of the mushroom cap and place the spore print in an area where it will not be heavily disturbed. Be careful to only use gentle pressure when scraping off spores, as any significant impact to the paper could cause most, if not all of the spores to release.

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