Depends on the dairy product. Butter, due to its low water activity, can be left out in cool temperatures for several days. If it's over about 80 degrees F, though, it can go rancid due to decomposition of the milk solids. Milk shouldn't be left out more than 30 min to an hour.
How do hazelnut trees produce hazelnuts? Unlike other fruiting trees, the hazelnut tree blooms and pollinates in the middle of winter. Wind carries the pollen from catkins (male flowers) to small red female flowers, where pollination occurs. The flowers remain inactive until spring, when fertilisation completes and the nuts begin to develop. The natural growth habit of the hazelnut is a bush, or multi-stemmed small tree as found in Turkey and Southern Europe. In the US, hazelnut trees are grown as single trunk trees that can grow to 5 metres or more. All varieties of hazelnuts require cross-pollination in order to produce nuts, so every planting requires two or more varieties.
The harvesting of hazelnuts is done either by hand or by manual or mechanical raking of fallen nuts. Common hazel is widely cultivated for its nuts, including in commercial orchards in Europe, Turkey, Iran and the Caucasus. The name hazelnut applies to the nuts of any of the species of the genus Corylus. This hazelnut, the kernel of the seed, is edible and used raw or roasted, or ground into a paste. The seed has a thin, dark brown skin, which has a bitter flavour and is sometimes removed before cooking.