Student research into bee mites, horse nutrition and natural remedies scooped the big prizes in the Far North Science and Technology Fair at the Turner Centre in Kerikeri last week.
More than 150 projects were entered in this year's fair, sponsored by Far North lines company Top Energy, with many thousands of dollars in prizes handed out at an award ceremony on Friday night.
The results showed once again that male domination of science is a thing of the past, with all but one of the premier awards won by girls.
The top award in the senior division was shared by Kerikeri High School Year 13 students Nicole Johnston, of Kerikeri, and Annette Pilapil, of Kaikohe.
Annette tested natural remedies such as tea tree oil, apple cider vinegar, coconut oil and manuka honey for their ability to suppress bacteria, finding that tea tree oil was the most effective overall.
However, the oil is volatile and can be an irritant, so she developed a blend of tea tree oil, manuka honey and apple cider vinegar which was suitable for wound dressings and more effective than any other remedy on its own.
Nicole found vitamin C levels in horse's milk, which is essential to foal growth, are influenced by the glucose content of the mare's diet.
She concluded that mares in early stages of lactation should be fed quality grass and high-glucose hard feed to ensure healthy foals.
Nicole has already been accepted for vet school at Massey University while Annette wants to study pre-medicine at Auckland or Otago.
Intermediate winner Malindi Reihana-Ruka, of Springbank School, wanted to know if organic, home-made Varroa strips — used to combat a mite which attacks honey bees — were as effective as commercially produced strips.
The 14-year-old from Tapuaetahi made strips using glycerine and oxalic acid, which is extracted from oxalis weeds, and found they were twice as effective as shop-bought strips. Her finding could have commercial implications.
The Years 7 and 8 winners were Joel White, of Russell School, and Maia Williams, of Kerikeri High School, respectively.
Joel's project explored the ability of seaweed to raise the pH of water and counter the effects of ocean acidification, while Maia's hands-on, muddy project researched the relationship between the size of mangrove trees and their distance from shore at three sites in Kerikeri Inlet.
Other projects examined ball-tampering in cricket; biological control of the notorious weed Tradescantia, or wandering willy; ''greenwashing'' claims by detergent manufacturers; rongoā Māori; the most effective possum bait (they are partial to Nutella, apparently); and much more.
Convenor Jackie Robertson said she was impressed by the standard of entries, which got ''better and better every year''.
This year's fair featured a large number of projects about bees and environmental problems such as introduced pests and ocean acidification.