馬占相思（大葉相思）的常見葉片是葉柄所異變而成，羽狀真葉只在初生的樹苗上出現．2008年1月12日在大埔洞梓苗圃中谷主偶然發現了一棵馬占相思出現不尋常的羽狀真葉現象．

此樹樹頂出現損壞，引至不能抑制樹幹上葉芽的生長．而這些亂生的新葉出現了初生時的羽狀真葉．在附近同年的樹 木並沒有出現同樣情況．

以此觀察，我們所說的羽狀真葉只在幼苗出現的現象，其實還有其他出現的可能性．

書本所得到的知識只是一些常見現象，在實地觀察才可以進一步瞭解樹木的生長狀況．<向大自然學習>不失為一個學習的好方法．

The leaves of Acacia mangium (commonly known as Big-leaf Acacia in this part of the world) we usually see are actually phyllodes (mutation of the petioles).  The bipinnate true leaves only appear when it is still a baby seedling.  However, when I visited Tung Tsz Nursery in Tai Po on January 12, 2008, I incidentally saw true leaves on a Acacia mangium tree.  How very extraordinary!

The top of this tree was damaged which could not inhibit the growth of leaf buds on the trunk.  The chaotic growth of new leaves emerged the true leaves which should only be seen when the tree was still a seedling.  Nonetheless, it does not happen to the other trees of the same age in its vicinity

From this experience, we see other possibilities for true bipinnate leaves to grow other than the usual seedlings.

The knowledge we get from books is the common facts.  We can acquaint ourselves more with trees in the field.  「Learn from Mother Nature」 is an excellent way to learn after all.

*translated by Mary Chung