How frost tolerant are peach trees and at what period of blossom and fruit does frost affect them?
The variety and cultivator of the Peach Tree will determine it's hardiness to cold.
Most Peach Trees are rated for zones 5-9, though there are some trees now for zone 4.
https://www.gardeningknowhow.com/edible/fruits/peach/peach-tree-care.htm
https://www.gardeningknowhow.com/edible/fruits/peach/peach-chill-hours.htm
https://www.gardeningknowhow.com/edible/fruits/peach/peach-tree-cold-protection.htm
Our Peach tree started to blossom in February when we had exceptionally warm weeks. Now it's just a bunch of sticks no live buds or leaf growth. Help!!!
Cold temps or fluctuations can certainly effect your Peach Tree buds.
You many not have Peaches this year.
https://www.gardeningknowhow.com/edible/fruits/peach/tree-with-no-peaches.htm
If my peach tree has been affected by leaf curl this spring, can I still eat the fruit from it if they are able to mature?
Peach Leaf Curl can effect the fruit by causing premature fruit drop, fruit that does not ripen or cause no effect on the fruit.
If you do have fruit, yes you can consume it.
https://www.gardeningknowhow.com/edible/fruits/peach/peach-leaf-curl.htm
I have two seven year old peach trees (not for sure of the variety)that for the previous two years has produced plenty of fruit. The first couple of years produce a small quantity. But for some reason this year, just like three years ago produced not one single bud nor fruit.. Nothing has changed as for the watering or fertilization of the trees. The trees look perfectly healthy. I'm looking for any kind of assistance that can help me determine the problem... Thanks in advance.
Not sure where you garden, but late season frosts are a common reason for peach trees not to fruit. Immature buds can get frozen off easily.
It that's not a possibility, you might want to Google Cooperative Extension for (your) County and find a nearby extension agent to talk with. Their help is free and they are usually super knowledgeable about the conditions, pests and diseases in their area. They're a great resource that many people don't know about.
Can you grow California peaches In Illinois
Here is a link that lists suitable Peach Tree varieties for you growing zone.
http://extension.illinois.edu/fruit/peaches.cfm?section=tree
Why is my peach tree dropping immature fruits? (I have already lost over 1/4 of the fruits that the tree started with.) Also, how do I keep birds and squirrels from robbing my harvest- netting over the entire tree?
The Limbs On My Peach Tree Have Little Dark Balls On Them. I've Sprayed Fungus Killer, Insecticides and Nothing Removes Them But Flicking Them Off. They Are Round Small Pea Sized And Crunchy Outer Shell And Sticky Inside. What are they and how or do I need to get rid of them?
Though I don't have an image of your tree 'pests', I believe your tree is infested with Lecanium Scale.
This link has more information on this pest and how to manage them.
http://www.extension.umn.edu/garden/insects/find/scales/soft-scales-deciduous/index.html