Trees die! It doesn't have to be a drought, they just die for various reasons! I've got quite a few dead ones on my woodlot. If they have leaves, I'm less wary but if it's just a dead stem with no leaves, just some of the main, bare limbs sticking up, that's a bit of a concern because one of those big limbs could fall. Since I wear ear protection, not hearing the tree crack is a concern. If I'm looking at the cut, I can't be looking up. Wondering... what about having a spotter and either he is standing right next to you and can tap you to run or he could tie a string around you and tug on it! However, reaction time is always an issue when you're dealing with only a few seconds. Anyone have insight on this? The other option is leave the trees alone. But, I would rather have them down on the ground so that they don't fall on me or someone as we ride my trails on ATVs. Unreal, I had a friend killed while he was mowing his lawn! A dead limb fell and hit him in the head. Way too young to go.
I’ve noticed that the dead limbs on my red oak trees tend to fall during or shortly after it rains. So perhaps the extra weight from the moisture ends up being the proverbial straw that breaks the camel’s back. Maybe avoid cutting those trees after a rain storm or when the wind is blowing. Trees with poor root systems also fall when the ground is saturated.
I felled a huge dead white oak last Fall. Only time i wore a hardhat (it was a construction type as thats all i had) Check to see if any limbs are entangled with neighboring trees as this could cause them to break when it goes. Have your diagonal escape route planned and well cleared beforehand. Make back cut, tap in wedges and when it starts, get out of there fast. You dont really need to look up just watch the kerf of your back cut. The tree i felled had lost the smaller limbs and had no obstructions. Its the tree im standing next to in my avatar pic. 37" stump white oak. I felled a small dead ash in early April see my thread DA vine intervention! I had no escape rout and one limb landed right next to me. You can see it next to the stump in the later pics. I shouldve had the hard hat then. Maybe not the smartest decision ive made. I guess the size of the tree wasnt that intimidating.
Like buZZsaw BRAD mentioned have your escape planned, cleared and when she starts get the hec outta dodge quick! I would think most of those dead limbs will start flying around when they start hitting other trees and tree limbs. I felled a few dead trees on the smaller side and a few of them were rotted out in the middle. Also a few times when I cut into them water shot out, scared the chit outta me! This could be very dangerous if you have a really big tree with the core damaged by insects. I only attempted these cuts because they were well back behind my home with no real threat of hitting anything.
Knowing is part of experience. Quite naturally you always look up before cutting a tree to assess the situation. You should be able to tell what shape the limbs are in and of course each type of tree has its own characteristics; that is some limbs fall rather quick and easy while others will hold on to them a long time and they don't tend to break until they are really punky. Of course it is never bad to have a spotter but as you state, communication is tough once the saw is running. It is the same thing as you mentioned; you can't hear a limb break when you are cutting. Be careful, make good decisions and wear some head protection.
Regarding your emboldened and underlined part above, I wouldn't be looking up to note when the tree starts to lean to fall, I am talking about the reason for this thread -- my perceived need to look at two things at the same time (which is impossible for one set of eyes)... the kerf as I am cutting AND the tree limbs that could fall. I have read and watched a bazillion threads and videos on felling trees and the one thing that is scariest is the unpredictability of it all. People get killed from the unexpected. Felling a 20 inch dead white oak that has only a stem and, say, a half dozen big, rotting limbs, who is to say that the vibration from making the cut might just be enough to cause a limb to fall? Would you hear it when it breaks? With ear muffs on and a ported ms362 screaming? Even with a hard hat a big, rotten limb could kill you.