Why begin with the weakest dilution, when doing a serial dilution plate count spread plate?

Question

Why begin with the weakest dilution, when doing a serial dilution plate count spread plate?

Answer 1

We count the number of baterial colonies on a plate to figure out the number of bateria we have in solution. For example, if a 0.1ml solution yeilded 10 colonies we can therefore estimate that 10 bacteria exsisted in out 0.1ml solution or 100 bacterial in 1ml solution.

We want to be able to count a relatively good number (ex. 50-100 colonies) on a plate to make it easy to figure out bacteria concentration. If we put the highest concentration onto a plate we would notice a 'lawn' of bacteria, which would not be useful to counting. Hence why we start with a weak dilution and move up from there to ensure that our counting is as precises as possible.