Northland's Te Rōroa people are asking families not to scatter the ashes of their loved ones under the famous kauri trees of Waipoua Forest.
Elders have spoken at a recent hui of their distress that the forest was becoming a dumping ground for cremated human remains.
Rick Parore, a local kaumatua, says bereaved families clearly don't mean to cause offence, but the giant trees should not be treated as an urupā.
Mr Parore says people have been turning up on a regular basis lately, and tipping their ashes at the feet of Tāne Mahuta.
He says tāngata whenua find that insensitive, and if families contact them, they may be able to suggest alternative arrangements.
The Waipoua Visitors centre has contact numbers for Te Rōroa elders.