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Just as I was sitting down to write my weekly blog post, my cousin sent me an email. She had received a bug-related item as a gift, and wanted to know more about it. Let's take a look:

(Photograph by Karen Gibson, used with permission)

Any idea what this is?

I'll give you a hint.

(Public domain image of Osmia lignaria from USGS Bee Inventory and Monitoring Lab Flickr Photostream)

This small bee is an blue orchard mason bee. It gets the name "blue" for its metallic blue-black color. The "orchard" part is because it is a significant pollinator of crops grown in orchards, such as cherries, apples, plums, and almonds. This bee and its relatives are called "mason bees" because they use mud in their nests, plastering it on like a human mason sticks together bricks with mortar.

Do you see all the pollen in the hairs on the underside of the bee's abdomen? Having large pollen collection areas, combined with the fact the mason bees visit more flowers per minute than other types of bees, is what makes them such good pollinators. In fact, just a few orchard mason bees can pollinate the same number of fruit trees as thousands of honey bees.

Back to my cousin's gift. Unlike carpenter bees, mason bees do not excavate nest holes in wood. Instead, they must find beetle galleries in tree trunks to serve as homes for their larvae. Nest holes may be in short supply in places where old tree trunks are removed right away. To help mason bees survive, you can provide a bee house like the one my cousin received. It is the insect equivalent of a bird house.

Building and Hanging an Mason Bee House

If you want to build a mason bee house, drill a series of holes 5/16 to 3/8   inches in diameter (smaller diameter holes may be used by leafcutter bees) six inches deep in pine or fir wood. Space the holes about 3/4 inch apart, the number and design are up to you. Paint and decorate as you wish. Mount the house firmly to fixed surface such as a wall or tree (the bees don't like their nest to swing). Place it where the house will receive early morning sun. These bees are usually active in the spring.

Do not rest the house on the ground, where ants and other crawling insects can get inside.

When a female mason bee finds the bee house, she will gather pollen and nectar into a ball called "bee bread" and put it deep within one of the tunnels. She will lay a single egg on the clump and close up a short chamber by plugging it with mud. Inside the chamber the egg will hatch into a larva, which will feed on the food its mother provided. In a short time it will complete development and turn into a pupa, and then finally an adult bee.

The female bee creates several similar chambers in a row within a single tunnel. You can see the inside of a nest about half way down this USDA page. When she is finished, she will cap the end with a plug of mud, a signal the nest is occupied.

(Public domain photograph of Osmia ribifloris by Jack Dykinga of the USDA.)

Depending on where you live, you might not attract the blue orchard mason bee, Osmia lignaria, to your bee house. There are roughly 500 species of Osmia around the world, however, so you may provide a nest for a related species that pollinates your local plants. For example, the Osmia ribifloris in this photograph is an important pollinator of blueberries.

If she doesn't mind, maybe Karen can send us an update later in the year letting us know if any bees found the house.

Please leave a comment if you have any questions about mason bees or bee houses.

One of our favorite bird-related activities, the Great Backyard Bird Count, is coming up this weekend,  February 16-19, 2018.

Great Backyard Bird Count

The Great Backyard Bird Count is a prime example of a child-friendly citizen science project. All you and your family need to do is count the birds you see over 15 minutes and then report your finding. Although it is called "backyard," you may count birds anywhere they are found, including parks, preserves, or fields. There is plenty of information and instructions about getting started at the website.

Are you a bird photographer? There is also a photo contest.

Related Activities:

Looking for children's books about birds?

1. Check out Taking Flight: a List of Children’s Books About Bird Migration at Science Books for Kids


2. The list of children's books for young birdwatchers at Science Books for Kids


You may also want to try:

Are you planning to participate in The Great Backyard Bird Count? What kinds of birds do you see in your backyard? We'd love to hear.

Here at Growing with Science, our activities are often inspired by children's books. Today for STEM Friday we are featuring four new titles in the Picture Book Science series by Andi Diehn and illustrated by Shululu (pen name of Hui Li), coming out March 1, 2018. For a review of the books, see our sister blog, Wrapped in Foil.

Activities to accompany and expand upon the books:

Let's discover more about the topics covered by the books through videos and hands-on activities.

1. Sun Energy

Energy: Physical Science for Kids explains what energy is through examples, such as chemical energy, heat energy, electrical energy, and light energy.

sunflower One question the book asks is whether plants use energy. After all, they don't run around, jump or even move.

Or do they?

Young sunflowers (and a number of other plants) do orient throughout the day so their leaves catch the most sunlight. You can see more in this video from Science News:

Plants are amazing because they can "capture" the energy from the light of the sun and convert it into chemical energy that we can use.

Sunflower Activity:  Plant a row of sunflowers in the soil. As they grow, observe how they leaves are oriented throughout the day. (Learn about plant parts, flower parts, pollination, and plant life cycles, as well.)

Related posts:

2. Force of gravity

In Forces: Physical Science for Kids, readers explore the concepts of gravity, friction, and magnetism.

Gravity is the force of attraction between two objects with a mass. It varies with how large the mass is, how fast it is moving, and also how close the objects are.

Let's learn a little more about gravity with this video from Crash Course Kids:

Buggy and Buddy blog has a great activity to show how the force of magnets can overcome the force of gravity.

  • Making parachutes is a good way to investigate the forces of gravity.
  • Making siphons is another way to find out more about gravity (Growing With Science Water Cycle, second activity).

Nomad Press has a children's book, Explore Gravity!, which has 25 hands-on experiments to try.

3. Matter

What are the states of matter? Solid, liquid and gas are the forms we are most familiar with. There is also a fourth state of matter called plasma, and very possibly others (up to six or seven). Plasma is the most abundant state of matter in the universe by far.

If it is so common, then why hasn’t everyone heard of it? One problem may be the term plasma. Plasma is a word also used for the fluid in blood that carries the cells and other materials from place to place. The same word  has two very different meanings, but that happens all the time in the English language.

The state of matter plasma is a gas that has been energized so much some of its electrons have come flying off. It can also be called ionized gas, but that is confusing because it sounds like it is just a special kind of gas. Plasma behaves differently from gas, and is thus a separate state.

In this video, we see the differences between the three states of matter we are most familiar with:


Explore the three most familiar states of matter using an ice cube

Place an ice cube or two on a flat surface outside on a warm, sunny day. Revisit it every twenty minutes and observe what happens.

Public domain photograph by George Hodan

Expected result:  The solid water (ice) should melt to liquid water. After it has finished melting, if the day is warm enough the liquid should evaporate, which means it has turned to gas (water vapor).

Related post about plasma

4. Waves

Waves: Physical Science for Kids relates the physical waves that we can see to light, microwave, and radio waves.

In our previous post, Exploring Waves with activities, we discussed how the water in waves doesn't actually move across the surface, but instead cycles up and down in place. This can be a difficult idea to grasp, but Andi Diehn nails it in her book about waves. She likens ocean wave movement to fans doing "the wave" at sporting events. Each person remains in the same seat, but by rising and lowering creates a wave of movement across the stadium.

To see the properties of electromagnetic radiation and how it travels in waves, see:


These Picture Book Science books introduce, define, and clarify the scientific vocabulary.  This is important because the physical science topics that these books cover are not mutually exclusive and the overlap can lead to confusion. For example, light energy travels in the form of waves; the force of gravity moves objects, giving them potential and kinetic energy; waves in the ocean can be harnessed to produce electrical energy, etc. Having a clear understanding of the concepts is an important first step to scientific discovery.


To explore the physical science even more, try 25 Items for a Hands-On Physical Science Bin

Disclosure: This book was provided the publisher for review purposes. Also, I am an affiliate with Amazon so I can provide you with cover images and links to more information about books and products. As you probably are aware, if you click through the highlighted title link and purchase a product, I will receive a very small commission, at no extra cost to you. Any proceeds help defray the costs of hosting and maintaining this website.

Come visit the STEM Friday blog each week to find more great Science, Technology, Engineering and Math books.