Look like a good outing.
1) why was my name mention here? Ranger? OK make sure you keep the park clean, no smoking in the park. Most important don't bring the insects home.
2) You are asking what to bring to the park, water, hat, etc etc... so no need to bring camera, you think you going for an excursion. Bring extra batteries, spare card, wear comfortable shoe & money to buy drink or lunch.
Wish you all have a fun outing.... one last thing, go to the washroom first at Sakura before start shooting cause no washroom elsewhere in the park.