The path changes colour to red as a sign that you should be on the look out for danger. Maybe it is a sign that you are near a cache.
Red does also stand for many oter things too, I do not know how many apply. Thanks to BourneCreative:
Red, the color of blood and fire, is associated with meanings of love, passion, desire, heat, longing, lust, sexuality, sensitivity, romance, joy, strength, leadership, courage, vigor, willpower, rage, anger, danger, malice, wrath, stress, action, vibrance, radiance, and determination.
Red is assertive, daring, determined, energetic, powerful, enthusiastic, impulsive, exciting, and aggressive. Red represents physical energy, lust, passion, and desire. It symbolizes action, confidence, and courage. The color red is linked to the most primitive physical, emotional, and financial needs of survival and self-preservation.
The color red is an intense color that is packed with emotion ranging from passionate, intense love to anger and violence — representing both cupid and the devil. It is a hot, strong, stimulating color that represents excitement and energy. Studies show that the color red can create physical effects such as elevated blood pressure, enhanced libido, increased respiratory rates, enhanced metabolism, increased enthusiasm, higher levels of energy, and increased confidence.
The color red is a highly visible color that is able to focus attention quickly and get people to make quick decisions, which is one of the reasons fire trucks and fire engines are usually painted red. Flashing red lights mean danger or emergency, while stop signs and stop lights use the color red to alert drivers about the dangers of the intersection.
Red represents power and courage. The color red is the basis of the traditional red power tie or red suit in business, and the red carpet for celebrities and VIPs. Red’s association with courage and bravery makes it a color that is used often in national flags, on shields, and in achievement patches.