July 9, 2010
Today we’re adding another entry to our "Summer Vacation Science" series. This one is adapted from an early book of Seymour’s called SCIENCE PROJECTS IN ECOLOGY. It is long out of print, but it is full of exciting opportunities that you can do with your kids during the summer, when you want to keep them engaged in learning and exploration.
A rotting log is far from being dead. Even after a tree dies and falls to the ground, it is host to a large community of living things. What kinds of things you’ll find depends upon what kind of tree it was, how long the log has been rotting, its location, and the time of year.
Materials You Will Need:
- A pencil and notebook
- A small shovel or trowel
- Small plastic bags
- Several wide-mouthed jars or an aquarium tank
- Fine screening to cover the jars or tank
- Vaseline petroleum jelly
What to Do:
Find a rotting log and look it over carefully. If it is hollow, look inside. Poke a stick and see if anything comes out. Small mammals often make homes inside these logs. You may find some larger animals such as mice, chipmunks, a rabbit, or perhaps a snake. Snakes like to hunt for food in logs because of all the living things there. Most snakes are very shy - they’ll hurry away as soon as you see them. But be careful. Even though the vast majority of snakes are not poisonous, many kinds will bite if cornered or handled.
Look on the outside of the log for plants growing there. You’ll often find different kinds of fungi and mosses. You may also find small seedlings of trees and wild flowers growing in decaying spots along the log.
Do you see any insects on the outside of the log? If you strip away a piece of loose bark, you’ll see that most insects live inside. Look for dusky salamanders, small frogs, or toads. You’ll probably see ants, millipedes, centipedes, slugs, land snails, spiders, sow bugs, and beetles of all kinds.
Use your shovel to dig into the rotting wood of the log. You’ll probably find passageways and tunnels of all kinds, some still in use, some left over from previous tenants. Examine the different degrees of rotting. Some parts may crumble away at a touch, while other parts will still be firm. As you dig down, you’ll come to the part of the log that is changing into soil. Here you’ll surely find earthworms, mites and springtails.
Look around you. Do different kinds of trees provide habitats for different creatures? Do logs that receive sunlight seem different from those that do not? Can you tell which ones have been dead for a long time and which ones recently fell? Be sure that you don’t take apart all the logs in one area - remember that these are homes for living things.
Take notes on all that you find and what you observe.
Questions to ask and things to try:
You can observe a rotting log community (and the living things that make their homes in this habitat) in your own home. Break off two or three chunks of the log with your shovel. Place the chunks in plastic bags, sea them and bring them home with you. Make notes about the conditions you found near the log. Was it in a damp place? How much sunlight did it receive?
At home, place the pieces of log in the wide-mouthed jars or in an aquarium tank. Spread a layer of Vaseline around the inside of the rim to keep any insects from crawling out. Cover with a fine mesh screening to allow for water evaporation.
Try to keep your rotting log terrarium under the same conditions that you found it. Water it from time to time as necessary, and keep it at about the same temperature and in the same light that you found it.
Observe the kinds of insects and other animals that appear from the log. Look for tiny eggs and put them in containers to see if they hatch.
- Do any plants begin growing from the log?
- Can you see any changes taking place in the log?
- What happens to the life of the log if you change some of the conditions in which you found it? For example, five the log more sunlight or more water. Do some kinds of living things seem to prosper and others decline? Do you think such things happen in nature?
Keep a daily log of the life of a rotting log.
There is an excellent Internet resource called Animal Inn which has even more activities that you can explore together in the woods this summer.
Posted by: Liz Nealon
