Part 9: Collecting Monitoring Data

Production

Measurement of production involves some evaluation of the standing biomass of the vegetation resource. First, let’s define some production terminology:

• Gross primary production is the total amount of organic material produced, above and below the ground over a year.
• Plant biomass is the total weight of the vegetation resource at any one time.
• Standing crop is the amount of aboveground plant biomass at any one time.
• Peak standing crop is the greatest amount of plant biomass present during a given year.
• Total forage is the total herbaceous and woody palatable plant biomass available to herbivores.

Some important considerations when measuring production:

• Standing crop and peak standing crop are the measurements most often used for range monitoring.
• Peak standing crop is generally measured at the end of the growing season; however different plants have different growing seasons.
• Research estimates that up to 25% of plant biomass is either consumed by insects or trampled primarily by grazing animals. This is relevant when trying to make a comparison between amount of biomass produced and the amount of forage eaten by livestock.
• This attribute can either be estimated, or it can be directly measured by collecting all above ground vegetative production, and then weighing it. The later can be quite labor intensive and may not be completed on a yearly basis.