Assistance Needed with APEX Crop Growth Simulation Issue

[Anmol Singh]

Dear APEX team,

I am reaching out to seek your assistance with an issue I am encountering in the APEX model. The model is not simulating crop growth in some years; during those years, the crop does not appear to grow.

I have tried several troubleshooting steps, including checking the weather data, using both calendar-day and heat-unit bases, adjusting heat units, and modifying planting and harvest dates. Unfortunately, I have not been able to resolve the issue.

One thing I noticed is that when I change the simulation starting year, for example from 1991 to 1992, the years with no crop growth also change. I could not identify any specific pattern. Another issue is that when I switch the simulation from a calendar-day basis to a heat-unit basis, the model simulates crop growth only for the first year, while outputs for the remaining years are zero.

Please find the attached .OPC file. Could you please suggest how I might resolve this problem?

Thank you for your time and help.

Best regards,

Anmol Singh

Graduate Research Assistant

Department of Biological & Agricultural Engineering

Texas A&M University | College Station, TX 77843

[Luca Doro]

Dear Anmol,

I don't see anything strange in the OPC file you shared. Would it be possible for you to share the entire set of input files you are using for your simulation?

Best,

Luca