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美国中西部各州苹果品种和生产趋势 据美国农业部1974年调查,中西部12个州苹果总面积为126824英亩,占美国苹果总英亩数的25%,报告指出,苹果株数占国家总株数的21%,其中 45%是矮化苹果树。 近5年期间,中西部特殊的气候变化,造成了苹果历年生产大幅度变化,然而1975年所有这个地区
According to a survey conducted by the United States Department of Agriculture in 1974, the total area of apples in the 12 Central and Western states was 126,824 acres, accounting for 25% of the total number of acres in the United States. The report pointed out that the number of apple trees accounts for 21 %, Of which 45% are dwarf apple trees. During the recent 5 years, the special climate change in the central and western regions caused a drastic change in the production of apples in the past years. However, in 1975, all this area