close
close
Roark: Plants that announce mealtime – Harlan Enterprise
Roark: Plants that announce mealtime – Harlan Enterprise

Roark: Plants that announce dinner time

Published on Monday, July 8, 2024, 8:00 a.m.

By Steve Roark

Contributing Author

If you’re out and about in mid- and late summer, you’re likely to see plants bearing fruit that go through various stages of color, especially blackberries now. Blackberries and several other wild fruits change from green to red and finally black or blue when fully ripe. Like almost everything in creation, color change has a purpose.

Plants produce fruit that we and many animals like to eat, and that is what fruit production is all about. They want their seeds to be spread and are willing to lure wildlife to do so. The animal eats the fruit for the tasty pulp and also swallows the inner seeds. It may run or fly some distance from the mother plant. The hard seeds pass through the animal’s intestines undigested, and when the animal eventually poops, it excretes the seeds along with fertilizer.

To ensure they are visible for consumption, many fruit plants display what are known as “pre-ripening fruit plumes” that go through a series of color changes as they ripen. Raspberries, cherries, mulberries, blackberries and blueberries are all green to begin with, turning pink as they ripen, then red, and finally purple, black or blue when fully ripe. This color change serves as a signal to animals that the fruit is about to ripen, encouraging them to stick around to feed, increasing the likelihood that the seeds will be dispersed.

Another trick some fruiting plants use is very early leaf coloration in the fall. The bright red or yellow leaves stand out clearly against a predominantly green background and are therefore attractive to animals (especially flying birds) from a distance. This early coloration is called the “leaf fruit flag” and is used by poison ivy, Virginia creeper, sassafras, black gum, Virginia creeper, dogwood, and spicebush to announce ripe or nearly ripe fruit.

Black bears in particular use the color signal of ripening. They are voracious eaters, especially in late summer and autumn, in order to accumulate enough fat for hibernation. They stay in one place for several days and eat the same fruit until it is used up. This excessive eating habit is called hyperphagia. So here too, simple things in nature have a purpose.

Next time you enjoy wild fruits, remember that you are being cheated. But that’s okay, because both sides win.

By Aurora