Category: Learning Outdoors (Page 30 of 63)

Seed of the Week: Cork Oaks

Last week for the mystery seed of the week I showed a photograph of an acorn. I’m surprised I didn’t get any comments from botanical types, because the acorn itself isn’t a seed. Generally one or two seeds are found inside the acorn casing.

Acorns come in many sizes and shapes, depending on what kind of oak tree they come from. There are over 200 species of oaks found in North America, but the species I’m going to show you today comes from the Mediterranean region. It is the cork oak, Quercus suber.

When my son and I read that cork oaks can grow in Arizona, I immediately called a botanically-minded friend. Yes, she knew where we could see one growing. We hopped in the car.

The first thing you notice about this glorious tree is its unusual bark. The cork bark is used for bulletin boards, flooring, gaskets, and wine corks. As long as it is removed carefully, without touching the cambium underneath, harvesting cork does not harm the tree.

This tree had a rich history. It was planted during WWII when cork was in high demand, but the supplies were largely cut off.

The tree has a lovely, open growth form with gracefully draping branches. I’m afraid my photos were not able to capture its elegant beauty.

Each acorn contains a wrinkly, veined seed.

Aren’t seeds marvelous? Have you ever seen a cork oak?

The Story of Ferdinand

When I see cork oaks, I always think of the book about Ferdinand the Bull with its delightful, whimsical illustrations of the corks on the trees.

(Affiliate link to Amazon)

Seed of the Week: Acacia salicina

Did anyone guess last week’s mystery seed?

These seeds are from Acacia salicina, a tree native to Australia but also grown in the southwestern United States. It has various common names, one of which is “willow acacia,” because of its draping, willow-like appearance.

The powderpuff blossoms attract bees and butterflies.

After pollination, the flowers produce these:

Any guesses what the bright red or orange fleshy structures next to the seeds are? Those are very interesting. They are called “elaiosomes,” meaning literally “oily bodies.” The tail-like parts are like a brightly-colored potato chip stuck to the seed. The birds eat the potato chip part and often carry off the seed with it. They drop the seed unharmed when they are done. The seed is thus moved away from its parent or dispersed. Botanically the structure is called an “aril,” which has to do with what part of the plant the elaiosome is derived from.

For a great deal more information about the genus Acacia, see The Unforgettable Acacias

And now, without further ado, the:

I was a little easier on you this week. What kind of plant grows from a seed like this?

If you’d like more information on trees, try these books:

(Affiliate link to Amazon)

Mosses, Ferns, Liverworts and Horsetails: Science Activities

Today let’s take a look at some plants that are often ignored because they lack big, showy flowers. Ferns, liverworts, horsetails and mosses do not produce seeds, but produce spores instead.

Activity 1. Identification

Go on a nature walk and see if you can spot any of these spore-producing plants. Record where you see them and what the surrounding environment is like.

Mosses are low-growing plants with tiny leaflets. They coat the ground like velvet.

Ferns have leaf blades divided into many parts.

Photo from Flickr

Liverworts have rounded leaflets that are said to resemble the liver.

Horsetails have tall stems, with segments. Their leaves are long and fine, resembling a horse’s tail.

Did you find any of these plants?

Activity 2. Searching for spores.

Because these plants make spores instead of seeds, it is fun to see if you can find the structure that produces spores, the sporangium. If you don’t have any of these plants growing nearby, check with your local florist. They sometimes use ferns in bouquets.

See the dark dots on the underside of the frond? Those are the sporangia.

Check out this video of fern spore capsules shooting out the spores like a catapult!

The yellow brown structures on this moss are the sporangia.

What is the difference between a seed and a spore? A spore is a single cell, so it is tiny. In comparison, a seed contains many cells making up the embryo of the plant, the food that is stored with it, and a cover or coat.

Activity 3. Moss, horsetail, fern and liverwort habitats.

When you went on the nature walk, where did you find these plants? Did you find them mostly in wetter areas? Were any growing in the forest?

Did you find them growing together?

Ferns, mosses, horsetails and liverworts have somewhat similar growing requirements. Liverworts and mosses are considered to be non-vascular plants because they lack the special water-carrying tubes found in other plants. They must stay in relatively wet environments and can’t grow tall.

Aren’t these interesting plants?

Edit: If you are interested in learning more, take a look at Steve Parker’s Ferns, Mosses and Other Spore-producing Plants book, which is part of the Kingdom Classification series. I have a review at WrappedinFoil.

« Older posts Newer posts »