The first flush of Japanese green tea is called "shincha", literally "new tea", and is prized in Japan for its delicate flavors.
There are several definitions of what is considered "shincha". The widest definition is refers to all spring harvested leaves in the first two months or so after harvest (when the leaves are still "new").
However, many farmers will harvest extra early for particularly young, tender leaves. These have several names: hashiri - "run", as "in run to the fields now to harvest the leaves", hatsutsumi - "first picking" or the farmer's very first harvest of the spring season, hachijyu hachiya - "88th night" referring to the 88th day of spring in the old lunar calendar, tea picked on this day is said to be the best and brings good fortune for the year (this year it is May 1st).