The phrase "a trail of red" is correct and usable in written English.
It can be used to describe a path or mark that is red in color, often implying something has been spilled or left behind.
Example: "As she walked through the forest, she noticed a trail of red leading deeper into the woods."
Alternatives: "a path of crimson" or "a line of red".
On it lies a trail of red, pulpy blobs -- melon and tomato?
Aerolineas Argentinas has been performing the trick for years, burning up repeated capital injections and leaving behind a trail of red ink (see chart).
School districts in three states are waging a battle against a spicy snack that is so laden with artificial ingredients it leaves a trail of red fingerprints behind.
A military parade is held on the Champs Elysées, and fighter jets, blazing a trail of red, white and blue, screech low over Paris.
His shirt was white except for a trail of red dots, possibly tomato sauce, that ran along one sleeve from his elbow to his shoulder.
There then followed in impeccable lines the veterans of Afghanistan and the two Chechen wars of the last decade, before nine fighter jets swooped down over the parade leaving a trail of red, white and blue smoke.
At the far end, a pitch-black corridor leads past a trail of "spilt" red paint, where a sudden spotlight shines on a wonky washbasin and a gushing stream of water – red water.
Certain things just taste better alongside a trail of ripe, red ketchup.
The pair's results, as yet unpublished, indicate a trail of old, red stars of a type also found in Sgr spread right across the Milky Way.
They left a trail of distinctive red pottery but few other clues, and scientists have confronted two different scenarios: The explorers were either farmers who sailed directly from mainland East Asia to the remote islands, or people who mixed with hunter-gatherers they met along the way in Melanesia, including Papua New Guinea. .
But he added: "If you're a novelist, you deliberately lay a whole trail of red herrings to lead away from the person you are writing about.
