We planted a 7 gallon spruce tree this May and it had been doing well until the last 3 or 4 days. We water every 6 days for 20-30 minutes with a slow flow hose. It gets a ton of sun, and we have had basically no rain this spring and record breaking temps this summer in Montana. But 4 out of 6 of the same trees we planted are doing well, and they are planted in a line on the top of a bank above a private dirt road.  No one has added herbicides, and there doesn't seem to be insect infestation (although insects are killing our much older douglas fir nearby with a top-down death as well.)

Is this one dying, as you can see from the wilting new sprigs on the top and can we save it? If so, how? Should we be watering more? As of now, temps are in the 80's day/50's night, but do go into the 90's at times.