Niche: Yagrumo

Niche: Yagrumo

Forest Niche and Life Cycle 

Me, lazy?! My sister is one to talk. She invented the word lazy. She sits around all day reading books while I’m out exploring in the forest. So who’s lazy? 

It is because I am out in the forest a lot that I see the yagrumo trees. I see that they grow in a lot of different areas of the forest as long as that area has plenty of sun.

Their niche, or their place in the forest community, is in sunny gaps of disturbed forest (read on). 

Most places in the forest are very shady. The open, sunny areas are usually where the forest got disturbed or destroyed. This could be from hurricanes, landslides, fires, or other disasters. Here in the rainforest, fires are not much of a problem.

A lot of tree species (such as the one I’m not allowed to mention) cannot grow in direct sunlight. It takes a special kind of tree or plant to grow in areas where the forest has been disturbed. These plants and trees are called pioneer species. They grow first in reestablishing a forest.

My father thinks I should talk about the life history of yagrumo. He wants me to summarize all the stages of its life. I'm not a noted scientist like him, but I'll try. OK, first we have a tiny brown seed about the size of a crumb. 

Many yagrumo seeds are scattered all over the forest floor. This is called a seed bank, like a bank where money is sitting around waiting for you to use it. The seeds can sit dormant (similar to sleeping) on the floor for many years. One day something happens that causes a gap in the forest. The sunlight pours in and, presto, the seeds germinate. They start to grow.

My sister is always trying to get me confused. She asked me (in front of my father) how the seeds know when it's sunny. Actually, I have to admit it was a good question.

I said, "Maybe they have tiny eyes," something dumb like that. I didn't know the answer. Of course my father did.

Yagrumo, he explained (in a lot more complicated way than I'm telling you), have pigments. Pigments are substances that absorb light. They produce a rainbow of colors in nature, including the typical green color of a plant.

Pigments are found in yagrumo seeds. They can actually tell the difference between shade and sun. When it's sunny, there's a higher amount of red color in the light. The pigments notice this. So when it's sunny, they say to the seeds, "OK, let's get going." The seeds germinate. More than half the seeds lying around on the forest floor germinate in sunlight; none germinate in shade. Cool, huh?