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美国黑核桃美国黑核桃是原产北美洲的野生种,与我国核桃是同科.在美国广泛分布从东海岸到中部20多个州。在分布区内1月份最低温度-6℃到最高温度31℃,年降雨量从635毫米到1778毫米地区都生长。黑核桃对土壤的酸咸度要求不严。pH值在4.6~8.2各种土壤都能生长。但最适生长区是由
American black walnut American black walnut is a native North American wild species, and our walnut is the same family in the United States is widely distributed from the east coast to the central more than 20 states. In the distribution area from January minimum temperature of -6 ℃ to the maximum temperature of 31 ℃, the annual rainfall from 635 mm to 1778 mm area growth. Black walnut on the acidity of the soil less stringent requirements. The pH value of 4.6 ~ 8.2 all kinds of soil can grow. But the most suitable area for growth is