Question

Growing in the shade- The ability to grow in shade may help pine trees found in the dry forests of Arizona to resist drought. How well do these pines grow in shade? Investigators planted pine seedlings in a greenhouse in either full light, light reduced to $25\%$ of normal by shade cloth, or light reduced to $5\%$ of normal. At the end of

the study, they dried the young trees and weighed them. Identify the experimental units and the treatments.

Short answer

The experimental units is Pine seedlings and Treatment is Full light ,$25\%$light and $5\%$light .

Step-by-step solution

Given information

We need to find that how well do these pines grow in shade and need to identify the experimental units and the treatments

Explanation

Here we need to find experimental units in this case ,

So by experimental design - the experimental unit is Pine seedlings

Experimental variable - Light intensity

As , light reduced to $25\%$ of normal by shade cloth, or light reduced to$5\%$ of normal in this case so,

Treatment - Full light ,$25\%$ light and $5\%$ light .