Science Buddies: "Ask an Expert"

Hi,
My project is the effect of pesticides on earthworm growth and it requires them to be alive for at least 8 weeks. I would like to know the favorable conditions that would keep them alive for the duration of my experiment (Given the fact I already have lost most of the earthworms due to some unfavorable conditions).

I already researched on how to take care of earthworms and received various inputs from different sources and I'm not sure which one's right. I would greatly appreciate if you could advise me on the following:
1. Temperature
2. Container in which they can be kept
3. Moisture level
4. pH level
5. Number of drainage and breathing holes
6. Whether water should be conditioned (no chlorine)
7. Recommended food dosage based on weight
8. Soil/bedding type

Thank you

Divya

Hi Divya,

Welcome to Science Buddies!

This will be a really great project and I definitely encourage you to continue. I am a veteran of a couple of earthworm projects, and I think all of the information you need about basic earthworm care is included in the following website:

http://www.earthwormworks.com/caring-fo ... worms.html

Do pay attention to the details like temperature and moisture, and keep your earthworms in the dark, where they prefer to be. For a science project, it probably best to use several containers that are as large as you can manage.

From experience, I can tell you that one of the most important factors for success in earthworm projects is to purchase your worms from a supplier that sells healthy worms; do not get the worms that are sold for fishing bait as these will not be healthy and may die quickly. If you do decide to try to collect your own worms, then dig in soil that is in reallythat is high in organic matter. Healthy worms will be very wiggly and you will have trouble holding them in your hand.

Now, please tell me what you are planning to do for your science experiment? What will your independent variable be?

K Hope this helps. Let me know if you have more questions.

Donna Hardy

Thank you so much for your help. I really appreciate it

My experiment is the effect of different levels of organic (cedar oil) and chemical (Malathion) pesticides on earthworm mass and growth. I just finished my experiment and all the earthworms in my control group survived. Half the worms in tub with the normal dosage of organic pesticides. I am currently doing research on why the earthworms died in the group with cedar oil. So far, I found out that cedar oil might have caused them to suffocate since they breathe through their skin. The dead ones were pale, limp, and extremely delicate (some even broke apart while I was holding them). I would really appreciate if you can share some ideas as to why they might have died due to cedar oil.

Also, all the earthworms exposed to malathion died. These earthworms were pulverized, strewn apart, and seemed to be excreting some sort of clear liquid. According to my observations, their skin may have ruptured or they may have burst. Although I did research on why this may have happened, I still don't have a clear understanding on why this may have occurred and would greatly appreciate your opinion on this.

Thanks again

Divya