Jewelweed

Impatiens carpensis

Habitat: Tall Grass Prairie, Eastern Deciduous Forest

Seasons: Spring to late summer

Active Chemical Ingredient

Palmitic-acid

https://en.wikipedia.org/wiki/Palmitic-acid

Use of specimen: A poultice made from the whole plant helps soothe irritated and burned skin, the poultice can also be used to reduce swelling, and it can also be used as an anti-fungal 

Source: http://www.thenaturelabs.com/article.php?id=36