Nail the exact color forest green in your design by using the code from any one of these systems for color identification.
|RGB||r: 34, g: 139, b: 34|
|HSL||h: 120°, s: 61%, l: 34%|
|HSV||h: 120°, s: 76%, v: 55%|
|CMYK||c: 76%, m: 0%, y: 76%, k: 45%|
If you're identifying color for pretty much anything digital, you're working in an RGB colorspace. If the project you're working on requires percentage representation, forest green is made of 13% red, 55% green, and 13% blue.
If you're identifying color for a print project, you're most likely using a CMYK colorspace—the percentages are 76% cyan, 0% magenta, 76% yellow, 45% black.