FAQ: Frequently asked questions


What is the Plant Cell Density Index (PCD)?

PCD, also known as the Simple Ratio Index, is a well-known remote sensing index used to characterise the relative health and biomass status of vegetation. Healthy, vigorous vine biomass will exhibit a strong near infrared (NIR) reflectance and a very low red (R) reflectance due to chlorophyll absorption:

Plant Cell Density =  (NIR 780nm / Red 675nm)

What does this mean in the vineyard?​

 Low PCD High PCD
Leaf and vine characterstics Lower vigour, greater plant stress, leaf senescence, thinner canopy Higher vigour, new shoots, green healthy leaves, fuller canopy
Fruit characteristics Potentially lower yield and higher quality fruit composition, even berry ripeness Potentially higher yield and lower fruit composition, uneven berry ripeness
Possible reasons
  • Advanced fruit maturity
  • Water stress
  • Nutrient deficiency
  • Disease/pests
  • Less favourable soil type, slope, aspect and exposure to sun
  • Retarded fruit maturity
  • Greater access to water and nutrients
  • More favourable soil type, slope, aspect and exposure to sun
Need help interpreting your V3 Maps for field management or harvest plans?
Contact us and we will refer you to your nearest precision viticulture consultant.