Gardening and what people don't know

 Chatting to the lady next door  who has a small pear tree.  It had one pear last  year when it had 12 the year before.  She had no idea why.

After discussion I discovered that she'd transplanted it from her mother's garden last year.  So transplant shock would account for a lot of it.

However, when I suggested adding some garden compost, she was surprised at the idea that it might need feeding....

She's no idea how to prune it either.  Fruit trees only bear fruit on horizontal branches - you have to prune regularly to get a good crop (I don't even have a fruit tree, and I know this, but my mother in law probably told me as she lived in an area with lots of orchards.)

She also didn't know that the flowers were where the fruit would eventually appear.  I was a bit flummoxed by that one.  I thought fertilisation of flowers was school biology level.

So, how much of what I assume to be general knowledge, is actually general knowledge?

How much do you know about where apples and pears come from?