Betula populifolia the female catkins erect. The fruit, maturing in autumn, is composed of many tiny winged seeds packed between the catkin bracts. The wood is medium hard and is used for high grade plywood, furniture, drum shells, spools and firewood. Like other North American birches, gray birch is highly resistant to the Bronze birch borer ("Agrilus anxius"). The leaves of the gray birch serve as food for various Lepidoptera, such as the leaf miner moth "Cameraria betulivora". Between about 1930 and 1950, many gray birch trees, along with paper birch and yellow birch ("Betula alleghaniensis"), were affected and killed by birch
Northern Hemisphere to draw air toward it in a counter-clockwise pattern. Hurricanes and tropical storms (massive low-pressure systems) spin counter-clockwise in the Northern Hemisphere. The shadow of a sundial moves clockwise in the Northern Hemisphere (opposite of the Southern Hemisphere). During the day, the Sun tends to rise to its maximum at a southerly position except between the Tropic of Cancer and the Equator, where the sun can be seen to the north, directly overhead, or to the south at noon dependent on the time of year. When viewed from the Northern Hemisphere, the Moon appears inverted compared to a view from