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发表于 2025-3-30 11:38:08
Pruning, enough to produce high quality sawn timber. A pruning regime for a plantation involves decisions about when and how often pruning should be done, how far up the stem branches should be removed and how many and which trees should be pruned. These will all be chosen to ensure the cost of pruning is m
gerrymander
发表于 2025-3-30 12:56:30
Pests,al problems involved with chemical control alone, it is desirable to use some or all of these strategies in concert in an ‘integrated pest management system’. Such systems are based around the natural circumstances of the pest. They aim not for a complete kill, but to maintain the pest at a level in
镇压
发表于 2025-3-30 19:59:14
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Nonporous
发表于 2025-3-30 22:53:22
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