Won't zinc kill the trees? Sorry if I seem like an ignorant hillbilly, but seriously, won't zinc kill the tree?

Poaky, pecans have a high requirement for zinc as a micronutient. Specialty pecan fertilizers always include zinc.

Jean, sounds like the trees have been visited by Sapsuckers, a common bird visitor to pecans. And, no, you cannot harvest green pecans. They won't ripen off the tree.

The pecans need to have started shucksplit to harvest. Once they start to separate from the nut, you can go ahead and pull them off and let them dry at least a few days before shelling.

Unfortunately the squirrels don't have to wait as long as we do. The nuts are edible to them for a few weeks before shucksplit.

well how do we keep the blankey blanks , squirrels(rats tree rats that they are)from stealing all of them??? they are up there everyday.....
thanks all
Jean

Hopefully none of the canopies can be reached from other trees nearby. If this is the case, you at least have a chance to put a dog next to the trees or a trap on the trunks or a barrier of some kind there at the trunks.

I can't really give advice because I've not been able to keep them from my little trees. The only have a couple pounds of nuts in each, but they have already cleared the first 4 of all nuts before I could get them, and have started on 5 or 6 more of the later maturing trees.

Several lengthy threads on squirrel management over at the Fruit & Orchards forum - just search for 'squirrel'.
I like the Big Bucket O'Death, but have a look here:

Here is a link that might be useful: Kania traps