Tropic of Cancer (0.468″) of latitude, or 15 metres, per year (it was at exactly 23° 27′N in 1917 and will be at 23° 26'N in 2045). See axial tilt and circles of latitude for further information. North of the tropic are the subtropics and the North Temperate Zone. The equivalent line of latitude south of the Equator is called the Tropic of Capricorn, and the region between the two, centered on the Equator, is the tropics. There are approximately 13 hours, 35 minutes of daylight during the summer solstice. During the winter solstice, there are 10 hours, 41 minutes of daylight. Starting
Macadamia tetraphylla have not done well in the pure tropics, with no fully successful plantations less than 15 degrees from the equator. Major plantations in Costa Rica, at 10 degrees north, are said to produce much less than in Hawaii at 19 to 22 degrees north, in one case 20% the production. Plantations in Guatemala at 15 degrees north are successful. However, individual seedling trees have produced well in the pure tropics and need to be selected. One grower noted that the integrifolia flowers in Costa Rica have no aroma, leading to low and erratic pollination. Macadamia tetraphylla has a higher sugar