Here at Growing With Science we love both creepy crawlies and science poems, so imagine our excitement when we discovered the new middle grade book, Leaf Litter Critters by Leslie Bulion and illustrated by Robert Meganck.
Each two-page spread in the book features a vocabulary-rich science poem about the leaf litter ecosystem, as well as a "Science Note," which is a paragraph or two of background information to support the poem.
For example, here's one of the poems (most are much longer):
snags maggots, mites, snails, and slugs
soil pest control
requires a flexible
appetite and abdomen
The accompanying "Science Note" explains how rove beetles fit into the "brown food web," and also how their abdomens differ from those of most beetles.
The digital illustrations add a fun element. They range from somewhat realistic to full-blown cartoon.
Leaf Litter Critters is a serious text that might just entice some readers who prefer fiction to explore a less-than-glamorous ecosystem. It's also perfect for those who enjoy their poetry on the sci-ency side.
Disclosure: This book was provided by our local library. 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.
Today we are joining with Share It! Science News blog in a kid-friendly investigation of composting. Here at Growing With Science we have activities to explore decomposition and the organisms found in compost. Share It! Science News is delving deep into composting with earthworms (vermicomposting). Be sure to go over and see what earthworm eggs look like.
Spring is a perfect time to add last year's compost to the garden and start this year's compost heap. While you are at it, why not incorporate some science activities for children?
Activity 1. Exploring Decomposition
Decomposition is an incredibly important process. Things rotting and decaying may not be pretty, but imagine what the world would be like without decomposition. Dead organisms would pile up and the nutrients tied up in them would not be released to be used again.
Test to see whether the addition of soil speeds up decomposition.
Note: The observation portion of this experiment will take two to four weeks depending on materials used, temperature, and humidity. Also, set up outdoors or in a well-ventilated area and warn children not to disturb, inhale, or eat decaying materials.
Clear containers, gallon-sized or bigger, if possible
Squares of fabric to cover container
Rubber bands to hold cloth covers in place
Plant debris, like leaves, grass clippings
Fruit and vegetable scraps, grains (no meat)
Soil, potting mix, or finished compost
Cup to measure soil and water
Optional: man-made materials (to check if they are biodegradable)
Prepare two containers with identical mixes of plant material and the same amount of water (enough to make damp).
Add a cup of soil, potting mix, or finished compost to one container.
Observe the two containers daily and record which one seems to contain materials that are decomposing more quickly. If there is a thermometer available, record the temperature of the mix each day. Add water as needed (same amount to both containers). Compare and discuss your results when completed.
Note: Too much water will cause anaerobic conditions or lack of oxygen. The microorganisms that grow under anaerobic conditions tend to smell really bad. If that happens and you want to try to save the experiment, pour off the excess water and stir in some dry leaves or grass clippings (same amount in each container).
Extension 1: Prepare more containers to compare the effect of adding soil versus potting soil and/or finished compost.
Extension 2: Add various man-made materials to test to see if they are biodegradable. Examples might be different types of packing peanuts, pieces of Styrofoam, pieces of plastic bags, cardboard, or different types of paper.
Activity 2. Discovering Critters in the Compost
A compost pile is a community of living things that are dependent on each other. Microorganisms such as bacteria, yeasts and molds are at the forefront of the decomposition process. Helping them (or eating them) are the invertebrates. The invertebrates help the microorganisms by tearing up or breaking up the larger pieces of plant material and by moving microorganisms about on their bodies. Remember that a compost pile that is working optimally will be too hot to harbor much besides microorganisms.
(Photograph of compost bin in public domain at Wikipedia)
Look through a sample of compost to see what critters are found hiding there.
Dissecting microscope, if available
Petri or specimen dish to hold sample
Tweezers, forceps or a small stick to poke through compost
Small paintbrush to remove debris and move tiny creatures
Paper and pencil to make drawings and record results
Identification guides, or take a look at descriptions of compost critters
What invertebrates should you expect? (Links go to related Growing With Science posts)
Crickets, cockroaches, some flies, and some beetles feed on the plant materials added to compost. The ants, riparian earwigs and most beetles will be feeding on other creatures living in the compost pile or bin.
Slugs and snails may feed on leaves of plants added to a compost pile and help break up large pieces.
Sowbugs and pillbugs also feed on decaying plants.
Nematodes (round worms)
Nematodes are by far the most abundant invertebrate found in compost heaps. They are tiny hairlike worms usually visible only under the microscope. It has been estimated that a single rotting apple may contain as many as 90,000 nematodes!