Elaeocarpus dentatus

A 1982 study suggested that North Island brown kiwi use the seeds as grinding agents to help break down food after analysing the gizzards of 50 birds. They found that around 50% of Gizzards containded Hīnau seeds and that the more seeds a kiwi had, the smaller the amount of grit present. This was also reflected in their finding that the seeds were all "abraded smooth," meaning they had been used for long periods of time.[16]

The North Island Brown Kiwi

In New Zealand forests the trunks of trees are crucial to flightless invertebrates who use them as a way to reach the canopy for food and breeding. A 1983 study used traps to study the kinds of these organisms that were coming up and down tree trunks of Hīnau over a 19 month period. The most prevelant speices coming up the tree trunks were Springtails makings up 39% of all the species. Wasps and ants made up 10%, Spiders 9%, Beetles and Weevils 8% and Mites 7%. The least prevelant species were termites and ant-lions who were not recorded at all. Coming down the trunk there were only 17% the number of (flightless) inverterbrates that were found coming up. The most common were the mites, making up 15%. Followed by larvae with 11%, springtails with 11%, and harvestmen with 9%.[17]

• 
  Springtails
• 
  The common wasp, an invasive species found in New Zealand.[18]

On Kāpiti Island Hīnau fruit is a very important food source for Kākā, as demonstrated by a 1997 study which radio tagged birds on the island to find out their sources of food. In March all the tagged birds ate mostly or almost entirely Hīnau fruit for the month, with males continuing until June and females stopping after March. It is unclear why but is hypothisised that the hardening of the drupes in the following months means that females, who have a different shaped mandible, cannot break into them as easily as males can. When Kākā are feeding their young on Kāpiti Island, they rely heavily on Hīnau and Tawa to do so. Both because of their prevelance on the island and their abundant crop of fruit. [19] They mainly eat the fruit by splitting them open and eating the still developing seed as the fruit only ripens in May, digesting an average of 7.1 seeds per minute in March.[19] [20][8]

Weka are important dispersers of Hīnau seeds but on the mainland, weka are quite rare and so most fruit on the ground is eaten by pigs and rodents, on predator free islands though, they disperse 76.5% of seeds - much more than their flying counterparts with only 13.7% of canopy seeds dispersed. Given that these areas are representative of New Zealand pre-pests it suggests that the majority of dispersal was by flightless birds and that now, after the extinction of most of them, weka have been given the task of doing the lion-share of dispersal. This makes them extremely important to the long term success of the Hīnau and the re-introduction to their historic ranges should be a priority. Though more research is needed, it appears that (Hīnau) seeds germinate better after the coat has been torn open and that the grit in weka gizzards abrades the fruit to a similar effect. It is yet to be seen how far and where weka disperse the seeds to, however, meaing the quality of their dispersal is not yet known.[21]

Kōkako eat both the leaves and fruit, though they make up a very small proportion of the bird's varied and complex diet.[22] The extremely hard endocarp is thought to be for protection inside the digestive systems of large flightless birds who acted as another disperser by eating fallen fruit. It is also possible, however, that it is to balance the over-eating of their fruit by parrots, like, for example the Kākā, which is described above.[23] Kererū also eat the fruit and act as a disperser, though not as much as weka do.[21]

In Māori mythology Māui discovers the origin of fire by stealing the nails of his grandmother Mahuika, the atua (God) of fire, extinguising each one. After realising that Māui had taken all of her fire she threw her last nail at him. It missed and landed first in the Rata (all species under NZ), Hīnau, Kahikatea, Rimu, Mataī, and Miro trees who rejected the fire. It then went on, landing in the kaikōmako, tōtara, patete, pukatea, and māhoe trees who received the fire, considering it a great gift. The trees that accepted the fire can be used to create fire by rubbing dry sticks together, those that do not, like the Hīnau, will not produce fire in this way.[30][31]

The mealy substance which covers the kernal of the Hīnau's Drupe (similar to that of an Olive) was used by Māori to make a kind of cake or bread.[32][33] Though the Drupes are edible raw, to make the cake they would first pound the fruits (the club made of maire or stone) in order to separate the nuts, stalks and bits of broken skin in a trough called a "kumete", leaving the course grey meal behind, a process called "Tuki." The meal is then sifted through baskets make of Cabbage tree leaves such that the stones are trapped in the basket, known as a "tatari" or "Kete puputu." They are then seived through a finer seive to make sure that none of the stones known as "karihi," "iwi," or "iho" escape. Afterwards, the meal was moulded into a large cake which is then cooked for several hours in a Hāngi, wrapped inside a Rangiora leaf.[33][34][35]

Although some Europeans claimed it had a "harsh taste",[36] Māori considered it a great luxury[34] as demonstrated in their saying: "Kia whakaara koe i taku moe, ko te whatu turei a Rua" meaning "When you awaken me from my sleep let it be for the purpose of eating the whatu turei a Rua (Hīnau meal). [33]

Despite European opinion, Elaeocarpus dentatus's seeds are in fact a good thing to eat as they contain some fatty acids which are protective against Cardiovascular disease.[37]

Because some meal was still left on the stones, water was used to rub the meal off the stones, the combination drunk as a sort of Gruel, as it would be called in a western context, and known to Māori as "wai haro."[33] It was also sometimes fed to sick people.[38]

The bark produces a brown dye which, when dipped in a ferrugineous swamp (one containing Iron), turns it into a bright and durable black colour.[39]

Young seedlings were tied with a knot and left to grow into the shape of a walking stick. They were then cut and used as such.[40] The bark was used to make bags which served various purposes, such as for the preparation of Raupō pollen bread,[41] and as water vessels.[42]