From the text, we know the fact that ______.

参考解析：

细节理解题。A项错误，文中没有说到红木给其他植物提供庇护所；B项正确，根据第一段最后一句“Biologists and tree experts keep its exact location a secret in order to protect the ecosystem around the tree.”可得出答案；C项错误，根据第三段第四句“However, coastal redwoods have another way to get water; they pull it directly from the air into their branches.”可知，红木还有别的方法来获取水分；D项错误，根据第二段第二、三句“Redwood branches begin 100 feet or more above the ground in an adult tree. The area where they start, called the crown”和第四段最后一句“The deal places become gardens where new plants emerge.”可知，大树枝枯萎了，烂了，那一块就会成为类似土壤的环境，富含矿物质，从而生成新的植物，这些植物生长起来的地方就叫做树冠，而不是D项中的falling branches。故选B。