Here is a summary of the provided article:

## Summary of CLM5.0 Updates Relative to CLM4.5

The article outlines the key updates to the crop and irrigation parameterizations in Community Land Model version 5.0 (CLM5.0) compared to the previous version, CLM4.5.

The main updates in CLM5.0 include:

### Crop Functional Types
- New crop functional types have been added.

### Crop Management
- All crop areas are now actively managed.
- Fertilization rates have been updated based on crop type and geographic region.

### Irrigation Triggers
- New irrigation triggers have been implemented.

### Phenology
- Phenological triggers now vary by latitude for some crop types.
- The ability to simulate transient crop management has been added.

### Crop Parameters
- Adjustments have been made to allocation and phenological parameters.
- Crops reaching maximum LAI now triggers the grain fill phase.
- Grain C and N pools are included in a 1-year product pool.
- C for annual crop seeding now comes from the grain C pool.
- Initial seed C for planting has been increased from 1 to 3 g C/m^2.

The article notes that many of these updates are also described in Levis et al. (2016).