About the flea problem. I have tried watering down tea tree oil and spraying that on my two dogs bedding and carpets. We are finding less and less fleas both on the animals and bedding. I think that being an oil, it takes out the oxygen and smothers the little b's. Good luck
I had two kittens that were infested with fleas. I was in a real jam because I had no money to put toward taking them to the vet. I did however have some Tea tree shampoo for humans and decided it was my only option. I lathered them both down in a big deep tupperware container with the tea tree shampoo and let them sit for 10 minutes or so with the lid on the container. they didn't like it much and meowed the whole time but it was for their own good. then I opened the lid and filled it to about shoulder height with warm water. the fleas were visibly running for high ground and several did try to jump out and even landed on my hands and shirt (wear a white shirt so you can see them) so I knew it was working. once filled to a safe height quickly put the lid back on with the kittens inside. they meowed like hell to get out but I knew they were safe and got thru it. I left them in for 20 minutes or so, took em out, rinsed off and picked a few visible fleas off them. the kittens came out fine, the dead fleas were in the water and I even found dead fleas falling off here and there hours later. the Tea Tree shampoo worked great for me and fortunately my kittens weren't allergic. I know this remedy isn't for everyone but if you're in jam and can handle the cute things whining your ears off it works just fine.
Tea tree oil will kill fleas, on your dog immediately, when mixed with baby shampoo. Leave it on and lather well, and most if not all the fleas will die, and wash out. This will not prevent the fleas from returning. You have to use a collar.
EC: WARNING! Tea Tree oil may be toxic to cats and dogs!
Pet Flea Control use
Tea tree oil has long been used as a method of all natural effective flea control by adding the oil directly to dogs, horses and sheep fur or their bathing water. Use on cats has been known to make them sick and in some cases kill them, this is due to cats licking their fur and consuming the oil.
According to National Animal Poison Control Center, the use of tea tree oil in dogs has been associated with hypothermia, muscle weakness, ataxia, tremors, altered behavior, paralysis. A case report has been published in which three cats had clinical signs and one cat died after being treated with the oil. 
Also read this feedback on Earth Clinic: http://www.earthclinic.com/remedies/tea_tree_oil.html#TOXICCATSDOGS
Will Ted's mange cure work on fleas?
For fleas - rub your pets with waxed mrytle leaves, then throw some small branchs of leaves behind furniture and in front of your return air handler. Fleas, mosqitoes and ticks do not like the smell and will find their way out of your place. It is a wild evergreen that can grow to 18-20 foot. Some people will have a skin rash if they touch it. It has a light evergreen smell but does not look like an evergreen tree it has leaves. It grows along ditchs and in dry areas. If you crush the leaf in your hand and it smells evergreen you found it.