Lung VQ Scan. Also known as lung or pulmonary ventilation (V) and perfusion (Q) scans. A lung VQ scan is an imaging test that uses a ventilation (V) scan to measure air flow in your lungs and a perfusion (Q) scan to see where blood flows in your lungs. It uses special x ray scanners outside of your body to create pictures of air and blood flow patterns in your lungs.
Yellow leaf spot, also known as leaf septoria, are caused by Septoria cannabis and S. neocannabina. These are fungal pathogens aimed specifically at marijuana plants. It is brought about by warm weather and rain and effect marijuana grown outdoors.
Yellow leaves are often caused by soil that is too dry; the reason soil that is too wet can also cause yellow leaves is that overly wet soil promotes root rot, which destroys the roots so they can't bring water to the leaves, so the leaves get yellow, just as they would if the soil were dry. Written Aug 25, 2015.