Hello and welcome aboard. Sometimes the Gallery section of the tree forum is less traveled so I will hazard my guess until the oak experts come along. I dunno why GW has to divide up the forums soooo much and hide posts. First, I assume Pin Oaks do well in your area. In most of St Louis they do great but there are patches where the soil is too alkaline or something and many there have yellow leaves and some defoliation. I would not want to fight nature for a hundred years like some of them folks are. The tree with the bare leaves in the first picture worries me. Rough winter after transplant stress maybe? My general advice in May is to give it a month to see if the tree rebuds. If not replace in the fall during prime planting season. The last picture to me looks to have a red tinge. Is it that or the small brown spots that have your attention? I don't know what part of the country you are in but we have had an odd week. 30's one night, 90's the next two days. I was amazed I did not see some foliage damage while I was mowing but sometimes it seems to take a few days. How has your weather been? Far as what to do to help them? Probably not much. Every few days stick a finger six inches or so into the soil and check on the moisture level down by the roots then do the right thing. Trees in general like deep watering while shallow rooted lawns like a bit at a time frequently. Good luck.

Live Oaks don't turn brown, ever. The leaves, when they do fall in the spring, remain green. Brown leaves mean that those portions are probably dead. What's your general location? What happened that caused the damage to this tree last fall? And what might be contributing to the problems with the other trees. Severe drought, construction activities, change of grade, etc. are examples of the kind of history we'd be interested in. Also, pictures help. Let us at least make sure of the identity.

A tree with some version of "leaf blight" is most certainly not "dying". Foliar issues are simply not the kind of thing that kills trees. As to exactly what pathogen or insect caused these lesions, I'd have to get out my big, big book of bugs, and my still bigger book of diseases of trees and shrubs. But you can do exactly the same thing on the device you posted this question with. Google is your friend, and I'd start with something like "Leaf spots on live oak-Texas" or some such.

2x Daily 10 mins ==>>> in my sand.. the tree woulld already be dead ... go out there ... and use a hand shovel and dig two or three holes.. down 6 to 8 inches.. AND FIND OUT ABOUT MOISTURE AT DEPTH ... DO SOME IN the root ball soil planted.. and find the edge and find out about native soil ... you are worrying.. because you are guessing ... that most likely was not grown in a pot for its life.. and when LARGE trees are field dug.. there is no real way to tell how slaughtered the root mass was .. so you cant really compare any two trees .. unless you bare rooted them .. in my sand.. having dug hundreds of holes.. and seeing what i see on your tree ... i would probably put A HOSE on trickle for 4 to 6 hours ... then i would be very sure.. the root ball.. and surrounding soil is moist ... not quite sure what i would do in clay.. since i never owned any ... imo.. newly planted trees really shouldnt be on drip irrigation ... mostly because you just dont know whats going on ... so go dig some holes with a hand trowel.. AND FIND OUT... and be sure to understand.. you need to get water thru the whole root ball planted.. a little surface water is not going to get 8 to 12 inches into any soil.. with a 10 min squirt ... and 6 to 8 inches down.. is where the roots are ... ken i might bet my shiny penny.. the soil so hard.. you wont be able to dig a hole with a hand trowel ... but thats a WAG https://duckduckgo.com/?q=hand+trowel&t=ffcm&iax=1&ia=images