Napa County voters will decide June 5 on a ballot measure that backers say is needed to limit tree removal in the name of vineyard development.

The Napa County Watershed and Oak Woodland Protection Initiative garnered 6,300 petition signatures, more than the 3,800 needed. Napa Valley Vintners, which represents more than 500 area winemakers, initially collaborated on the creation of the initiative, but later its board of directors voted to oppose it.

Wine tourism in the county in 2016 drew 3.5 million visitors and spun off $80.3 million in revenue.

County supervisors Tuesday voted unanimously to place the measure on the ballot. About 30 people spoke before that vote — roughly split between opposition and support of the measure.

Critics said the measure was misleading and without scientific support that its passage would improve water quality. Some said wine industry was already regulated. But they added having it on the ballot will allow a campaign to educate the voters on why it should be defeated.

Supporters took similar approach that presented with the facts that voters will understand the need to establish protection for the trees and watershed “now and into the future.”

Supervisors commented that placing Measure C on the ballot would allow voters the choice of an up or down vote. The alternative would have been for the board to adopt the measure’s provisions.

One supervisor, Belia Ramos, said it was not the best way to govern.

“I will respect the initiative process, but as far as good government, I do take issue with it,” Ramos said. “The five of us have not been told what is wrong. We have just been presented with the measure — either adopt it or put it on the ballot.”

The Watershed Protection Committee, authors of the initiative, say expansion or creation of new vineyards into oak and other woodlands in California’s premier winegrowing region is adversely affecting fish and wildlife.

The initiative would establish buffer zones along streams to protect water quality and limit destruction of oak woodlands, they say.

Opponents of the measure, however, are taking issue with part of the initiative that states that after 795 acres of oak woodlands in the valley have been removed, they must be replaced at a 3-to-1 ratio. The base for measurement — called the “oak removal limit” — is Sept. 1 of last year.

At issue are unanswered questions in the initiative around exactly how many trees can be removed and for what reason. For example, does the cap includes trees needed to be cut down because of the wildfires in 2017?