APSIM LAI simulation curve sudden drop

[JoannaYRS]

Hi, I've noticed that the APSIM-generated maize LAI simulation seems to have a sudden drop at the end of the season, as the figure below shows. I've also come across some relevant studies, like Jin et al. (2017), that showed similar simulated curves. However, other crop models such as WOFOST don't exhibit this pattern. I am wondering the reason behind the sudden drop. Thank you for your explanation.

Jin, Z., Azzari, G., & Lobell, D. B. (2017). Improving the accuracy of satellite-based high-resolution yield estimation: A test of multiple scalable approaches. Agricultural and Forest Meteorology, 247, 207–220. https://doi.org/10.1016/j.agrformet.2017.08.001

[peter-devoil]

Most of the grain crops will "switch off" at physiological maturity - which is why we've never done ratoon/regrowth crops. Perennials like lucerne will, but strangely not if they've set grain - showing its pedigree from an annual crop model.