Yarrow Border External use Externally a decoction is used as a herbal remedy to deal with slow-healing cuts, skin rashes and eczema, chapped skin and in the form of a gargle and bath additive. Yarrow should be consumed in moderation and not for long periods because doing so might cause skin itching.

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Yarrow – First Among Natural Herbal Remedies?.. Part 2

  Herbal Infusions and Decoctions Tea is a water extract of herbs called an infusion .

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Medicine Making Basics ~ Herbal Infusions

Drying and Preserving Roots, Herbs, Barks. General – collect herbs when the weather is good and when there is no dew on them. Dry them in the shade, after which they ought to be protected from exposure to the air by wrapping up inside paper or perhaps keeping in paper pouches, tied up and hung up

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Basic Harvesting, Processing and Preparation Of Medicinal Herbs