Different shades, tints, and hues of green have different meanings. For example, dark green represents greed, ambition, and wealth, while yellow-green stands for sickness, jealousy, and cowardice, and olive green represents the traditional color of peace.
The Columbian Exchange is a term used to denote the world-changing exchange of agricultural goods, slave labor, diseases, and ideas between the Eastern and Western Hemispheres that occurred after the year 1492 CE.
As you can see there were many good things traded int the Columbian Exchange. Bad things that were traded was disease. Now disease wasn't traded on purpose, but it still got traded in a way.Other bad things that were trades accidentally was pests. Pests are rodents and bugs like roaches and rats.