There is a growing repair bill for vandalism of kauri dieback stations, in what seems to be deliberate attack.
Ripped fencing, stolen spray guns and brushes and broken hygiene stations have been reported, with a cost of more than $100,000.
Kauri Dieback Management senior ranger Stu Leighton said some of the vandalism appears to be targeted.
"Vandalism has always occurred in regional parks but the specific and deliberate damage to track barriers, signs and the wilful cutting of sterigene lines would appear to be a form of protest and that's the frustrating piece. We are keen to get more tracks reopened for summer but this behaviour isn't helping."