A DC electromagnet is simply a coil of wire connected to a DC voltage source. It can have an air core or an iron core.
Northern Highbush Varieties. High Chill Varieties. Northern Highbush varieties are the most widely planted blueberries in the world. They grow best in temperate climates where total winter chilling is 1,000 hours or more.Except where listed, most Northern Highbush varieties are relatively self-fertile.orthland is the one of the most cold-hardy Highbush varieties. It is vigorous, easy to grow and adaptable to different soil types and conditions. Northland yields are heavy and the berries are sweet with high sugar content.
Species in the section Cyanococcus are the most common fruits sold as blueberries and are native to North America (commercially cultivated highbush blueberries were not introduced into Europe until the 1930s).he flowers are bell-shaped, white, pale pink or red, sometimes tinged greenish. The fruit is a berry 5â16 millimeters (0.20â0.63 in) in diameter with a flared crown at the end; they are pale greenish at first, then reddish-purple, and finally dark purple when ripe.