Bees are needed for some plants to bear fruit

These beans didn't need bees. 

A fellow blogger was wondering why his zucchini plants are not producing foot-long zucchini like his neighbor's plants. It turns out, something is missing: bees.
Bees are needed to pollinate squash, cucumber and melons. These plants form both male and female flowers. Humans can intervene by transferring the pollen from the male flowers to the female flowers.
There are vegetables that don't need bees or other insect pollinators, such as peas, okra and most beans. There are also plants that (some say) can be self-pollinated with help from the wind, such as tomatoes, peppers, kale and corn. This is currently a topic of debate, so I'm waiting for the experts to decide and let me know.