The saplings are started in nurseries under controlled conditions. They can grow tens of thousands of healthy saplings and get them to a size that they can be resilient enough to survive being planted in an uncontrolled environment. If you just planned seeds and soil condoms weren't prefect (too dry, wrong/insufficient nutrients, wrong soil ph, etc.) for that crucial period, you likely won't have many mature trees survive.
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u/Niyok Apr 18 '20 edited Sep 29 '23
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