Gravelle said:

My parents are having problems with both the golden finches and purple
finches eating the sweet corn they have growing in their garden. What can
be done to keep them from doing this?

In my garden, the worst offenders seem to be cowbirds and starlings.
They start pecking at the ends of the ear and slowly shred the husks back.

(Tiny scratch marks and bird poo are pretty convincing evidence that it's
the birds, even if you haven't caught them in the act.)

I take heavy duty paper lunch bags and pull them down over the ears
(after the silks have started drying). The only problem is that when
the bags get wet, the birds can tear through them. This is less likely to
happen if you leave a good 'air gap' above the ear. I have small 'tents'
made of hardware cloth which I use to protect sunflower and squash
seedings from birds, which I've had to use to supplement paper bags
when the birds have been very persistent.

I'm toying with the idea of making cloth bags from old sheets...

A local sweet corn grower (for a farm stand) uses those 'terror eye'
balloons you see in some seed catalogs, with lots of flash tape streaming
from them. Don't know if that is truly effective, or just a sign of
desperation.

(I don't want to chase all the birds out of my garden, just stop them
from eating my corn.)

--
Pat in Plymouth MI ('someplace.net' is comcast)

Any technology distinguishable from magic is insufficiently advanced.
(attributed to Don Marti)