I put my hoses away when the nights start freezing consistently. By that time unless I blow them out each time, the water freezes inside and it's a pain to use them. Good move watering your new trees well into the fall NYboy. Going into the winter dry is probably the biggest killer of new plantings. I like to give everything a good soak up until the last day that's it's convenient to leave a hose out.
They should be watered in the winter from what I have read. Winter rain and snow is usually enough. A prolonged drought should bring out the hoses on a warmer winter day.
If one waters too much throughout the first year one will end up with plants that mostly have surface roots with too little deeper roots so they are set up for failure in dry years to come.
In dry air areas some trees, especially evergreens, get overhead sprays of water once every few weeks. Same for some of the deciduous ones if the soil is dusty dry.