In article .com,
(known to some as ) scribed...

There is a heavy wire running from the outside phone box (company side)
to a big spike in the ground. I clipped that with hedge clippers some
years ago, then I repaired the break merely by twisting the ends back
together and that worked okay for many years..

Not good. At the very least, you need to use an appropriate wire
nut rated for outdoor use. Simply twisting the ends together is not
enough.

Today there is a bad, constant hum on all phones. When I plugged a
phone into the outside box jack, the hum was the same. It has also been
raining for several days.

Can a bad ground cause a hum? Vigorously shaking the ground wire caused

Not quite. What CAN cause the hum you describe is a partial ground
on one side or the other of the line. Since the noise is present
directly at the box, you need to call your local phone company to make
repairs.

no static. What should I expect if I disconnected the ground entirely?

NO! NONONONONONONONOOOO!!!! Let the phone co. re-do the ground.
Disconnecting it and leaving it that way is a violation of Natl.
Electrical Code, and can get you in dutch with the telco if they find
out you had an accident with it with your hedge trimmer.

Best thing to do is simply get your telco repair person out.
They'll see the ground, but you can simply say something like "Huh?
What's a 'ground wire?'" and they have no way to prove you messed with
it. They'll fix it, along with your hum problem, and all should be well.

Also, there was a wasp nest in the customer side of the outside box
(but not in the company side). The nest didn't seem to create any
obvious destruction, though. If I connect a phone to the jack on the
customer side, then the nest seems to have no involvement anyway since
the terminals on that side become irrelevant - but you never know.

Warn the tech about that before s/he starts work. The nest may be
dead at this point (it is, after all, getting into winter), but they
appreciate knowing about such things.

Keep the peace(es).



--
Dr. Anton T. Squeegee, Director, Dutch Surrealist Plumbing Institute
(Known to some as Bruce Lane, KC7GR)
http://www.bluefeathertech.com -- kyrrin a/t bluefeathertech d-o=t calm
"Salvadore Dali's computer has surreal ports..."