I promised you some answers to last week’s quiz, and they’re at the bottom of the page. First, however, here are some pictures to remind you that Saturday is Valentine’s Day.

Zebras, Cheyenne Mountain Zoo

Prairie Dogs, Big Johnson Reservoir, Colorado Springs

Lionesses, Denver Zoo

Swainson’s Spurfowl, Kruger National Park, South Africa

Eastern Fox Squirrels, Lettuce Lake, Tampa, Florida

Continue for quiz answers…

Quiz Answers

• Why is it a bad idea to use a string trimmer (aka weed wacker) to cut down weeds around the base of a young tree?

Have you ever seen what happens when that stinging string encounters tender bark? Here’s one example (right). Yes, it quickly tears through the thin bark layer and destroys the phloem underneath. Girding the tree kills it—death by weed wacker.

• Why are deciduous plants and perennials harmed more severely by a big hail storm that occurs in June compared to one that occurs in late September?

In June, those plants have just used up the sugars stored in their roots to put out new leaves. If they are defoliated by hail, the plant lacks the resources to start over. But in September, those roots are full of energy stored against the coming winter. The plant can either grow new leaves, hoping to recoup the cost before a killing frost, or simply stay bare and wait for spring. Much depends on the weather that follows the storm.

• Why do beets and carrots contain more sugars than spinach and broccoli?

Beets and carrots are storage roots, so one of their jobs is to be a receptacle for the sugars made by the leaves. Since both these plants are biennials, they need to store up enough food to overwinter and then re-sprout, bloom, and produce seeds. Spinach leaves make sugar, but it’s used for growth and flowering. Broccoli is a flower—it’s sugars will go into seed production.