We live in the country in a house surrounded by woods, with a swimming pool, as well as ponds about 1/4 mile from our house.
We always wear a cap outside other than in the pool because of the proximity of the trees to our house and pool deck.
Best thing to do if you got younger brothers or sisters like I do, is check their hair and yours if you are outside and do not have a cap on. And friends that are girls.....they need a cap too. My girlfriend has long hair so when she comes over if we are outside a lot or walk down to the pond, she always wears hers.