Well....sort of. If it's a female flower anyhow. Male flowers will not produce a pumpkin. Notice the difference below? The female shows signs of the future pumpkin fruit, the male doesn't.
Just like our hens need a rooster in the coop with them in order for her eggs to be fertile. The female pumpkin flower needs a male flower present to pollinate her. However, being that they are just flowers, they need our help! We can pick the male flower and self-pollinate the females but this would take Farmer Pat an awful looonnnnng time to do 6 acres of pumpkins, so we depend on bees.
In fact we have a local bee keeper bring a pallet of bee hives to the farm to help in the pollination process. I'll try to remember to take a picture and post the hives. Hope I don't get stung...ouch!