Potometer

Petometer - a measure of transpiration

Measuring transpiration is hard because it's difficult to measure the exact loss of water from plants.  But 99% of water which is taken in is lost, so measuring the amount of water taken in is an accurate measurement.  To do this, we use a petometer.  This is how one works...

• The shoot of the plant is cut under water, with care taken not to get any water…