After flagging the campaign vehicle, Kumar said he had already handed over a cheque of Rs 99,500 to state party president B N Singh.
State Water Resources Department Minister Vijay Kumar Choudhary, who was also present, said he had also donated his one month's salary for Rs 98,000 to Singh.
Speaking on the occasion, the Chief Minister appealed to his party's 18 ministers, 115 MLAs and 37 MLCs to follow suit by contributing their one month's salary each to the party for the Green Bihar Campaign.
Kumar said his party had decided to enroll fifty lakh new members to achieve the target of planting fifty lakh trees in Bihar.
He said the party would be giving membership on the condition that the person would be planting one tree each.