Plant monitoring has grown over the last 10 years from a research tool focused on pre-harvest quantification of fruit retention patterns into a set of tools that producers can use to assess crop status during the growing season. Producer utilization of these plant monitoring tools has been successful because these tools provide guidance for using specific production inputs. This linkage between plant monitoring tools and production inputs is strongest (i.e. most quantifiable) where large data sets have been developed to define average plant monitoring parameters and where input response trials have been plant monitored.

A coordinated plant monitoring program was established in 1992 to develop a large data set of fields from which to determine average and ranges of plant growth for different growing areas, through the Nation Cotton Council and funded as a special project by BASF Corporation. Over 130 commercial fields were identified based on a diversity of yield history and representation of soil and environments within the U.S. Cotton Belt, for intense data collection. Field production histories and a record of current year inputs (variety, planting date, fertilizer, PGR's etc.) were collected from the producer. These fields were monitored weekly for height, nodes, bloom location and first position fruit retention. Just prior to defoliation, fields were plant mapped to describe the location of all fruit on the plant. Yield and HVI quality were also collected.

During the first week of bloom, the 130 field average plant height was 25.8 inches, Nodes Above White Flower 7.30, first position square retention 81.4 %. During the fifth week of bloom, plant height was 36 inches, Nodes Above White Flower 4.30, first position square retention 69.7 % and first position boll retention 59.6%. Current plans, are to develop regression equations for plant growth parameters in high and low yield production areas and expand this data set in 1993 and 1994.