Part of being inquisitive is asking "why." "Why" is an especially good word on a nature trail. For instance, you might find yourself asking, "why am I suddenly walking in a ponderosa pine forest? Why is it here?" For an answer, you need to consider two things, moisture and soil. 

Moisture is necessary in every community. The movement of water through the soil and the amount of water available to vegetation is influenced by soil texture. Because ponderosa pine trees grow best on well-drained, silty soils they are usually found on the park's hilltops where this type of soil exists. These pines seldom grow in the middle of the prairie due to unfavorable soil conditions and a lack of moisture.

Moisture is also important for the germination of pine seeds. Once germinated, the nourishment contained in the seed enables it to send down a fast-growing tap root. Because this root grows deeply, the seedling can better survive wind and drought. Look for seedlings as you walk. Do they grow close together or far apart? Why would this happen?