The most obvious phenologic event this time of year is the splendid display of color in deciduous trees just before the leaves fall. As the green chlorophyll is gradually withdrawn from the leaves, remaining compounds become visible, treating us to striking red, gold, orange, brown and bronze colors. The DNR has a wonderful map, showing where the best colors can be found. The Twin Cities metro area is approaching peak colors, so this is a great time to be outside enjoying the views.