Obviously my favourite topic as that is the only thing thriving in my garden. Here is some other use for them aside from scrubbing pans.
Some information from my tribe's Nutritionist with resources from wildfoodsandmedicines.com and the Northwest Indian College Institute of Indigenous Foods and Traditions.
When and how to harvest: Fertile shoots appear from late March through mid-April. Harvest the newer shoots that are still golden at the flowering tip. Each node of the stem stores water and kids love to pull them apart and drink the liquid inside. The fertile young shoots of horsetail are considered a spring delicacy. Pinch off the stem close to the ground. Remove the brown sheaf around each node at the cone-like tip. The tender growth between the nodes is eaten fresh and is traditionally dipped in oil. It can also be cut up and added to soups or sautes.
Horsetail Spring green tops:
Spring green tops are gathered when the leaves are still vibrant green and pointing upward or outward, usually between March and July. As the pants age, leaves begin to droop and turn army-green. Silica crystals in the laves become more developed and less water soluble-and therefore, less useful for human consumption.
Horsetail tea as medicine: Horsetail has a mild vegetable broth-like flavor. Prepare a strong infusion with a large handful of herb per two to three cups of water. Steep 15 minutes to several hours. Drink up to 3 cups a day.
Horsetail combines will with other herbs. A popular tea at the Northwest Indian Treatment Center in Washington is "Healthy Skin, Nails, Hair, and Bones tea". It contains equal parts horsetail, red clover, stinging nettles, and peppermint.
One heaping teaspoon of this mixture is steeped in a cup of boiled water for 15 minutes to several hours. Delicious!
The tea can be applied topically for recovering from sunburn or poor quality skin with premature aging.