When Heated, Why Does Iron Melt While Wood Burns?

I recently visited a foundry where I saw iron being melted into different shapes. It got me thinking: why does iron melt instead of burning like wood when heated. 

Iron is a homogenous element that cannot be further separated into simpler elements while wood is a compound made up of several elements.

Some of the elements in wood are cellulose fibers, lignin and water. These elements have a wide range of melting and boiling points. For example, water evaporates at 212 °F (100 °C),lignin melts at around 482 °F (250 °C) and cellulose fiber melts above 500 °F (260 °C).

When heated, some of the elements that have lower melting or boiling points ignite or evaporate before the higher melting temperatures are reached causing the wood to decompose as heat and light, which we call fire. On the other hand, iron remains stable enough to reach its high melting temperature of 2800 °F (1538 °C).