The farmer plowed \( \frac{1}{4} \) of an acre in the morning and \( \frac{1}{4} \) of an acre in the afternoon.
To find the total acres plowed, you can add the two amounts together:
\[ \frac{1}{4} + \frac{1}{4} = \frac{2}{4} \]
Now, simplify \( \frac{2}{4} \):
\[ \frac{2}{4} = \frac{1}{2} \]
Thus, the total amount of land the farmer plowed is \( \frac{1}{2} \) acre.
So, the final answer is:
\[ \frac{1}{2} \text{ acres} \]