Problem: the deer and rabbits think my yard is one big salad.
Solution: a home brew to teach them to leave my plants (and baby trees) alone--without hurting the critters (as far as I know):

DEER & RABBIT REPELLENT

1 egg, beaten
1/2 cup milk
1 Tbsp oil
1 Tbsp liquid dish soap
1 tsp garlic powder

Mix together, pour into a gallon jug and fill the jug with water. Shake well and transfer to spray bottle as needed. Label both. Shake spray bottle well before each use. For the first month of "training," spray generously on plant leaves once per week or after a rain, then spray once per month after that.
Do not spray on anything you plan to eat!

Now for the super-annoying, I-can't-believe-I'm-writing-this, anti-lawsuit disclaimer: Follow safety precautions. If you have a question about a product, contact the company. Test on an inconspicuous area first. Keep out of mouth, eyes and skin. Wear goggles and cleaning gloves or a haz-mat suit if you need to. Keep out of the reach of children and pets. If irritation develops, discontinue use. Use your head. (Okay, not literally...oh dear.) Do what works, and don't blame me. :)