The nitrogen bill when you return straw
Carbon without a little N is a tug-of-war at the seedling.
- After straw return, seedlings yellow like nitrogen lack.
- Microbes eat first.
- Badly diseased straw should not go back on the same family. Yellow can also be disease.
- Straw stealing nitrogen is one cause of nitrogen shortage.
- Don’t treat the IOU as a yield doubling; don’t sow thick under long straw with no N.
- Add nitrogen: A few kg urea per mu, by how much straw. Follow the local agronomist, and watch nitrogen steal
- Name what you see before you feed.
- If leaves, roots and the surface disagree, stop.
What you see in the field
After straw return, seedlings yellow like nitrogen lack. Microbes eat first.Rub a handful next to a darker neighbour that still forms crumbs. Pale dusty soil that leaks after rain matches this page. Yellow leaves are extra — first ask whether the soil still has body.
Tap to enlarge. The caption says what to photograph. Missing field photos are marked as to-be-added.
Why it looks like this
The field looks like this because the root cannot take water or nutrients the usual way. Fix the soil condition first — drainage, salt, acidity, compaction or a salt of fertiliser — then a thin feed. Rates live in the range on this page; confirm with a local station and the label.
Easy to mix up
Looks like “Diseased trash”
Badly diseased straw should not go back on the same family. Yellow can also be disease.
Looks like “Nitrogen shortage alone”
Straw stealing nitrogen is one cause of nitrogen shortage.
Do this / don’t do that
- 1After straw return, seedlings yellow like nitrogen lack. Microbes eat first. Compare the worst plants with a neighbour ridge before you add a bag, or the next step will chase the wrong thing.
- 2By straw amount and extension, often a few kg urea/mu class to pay the IOU. Chop and press.
- 3Don’t treat the IOU as a yield doubling. Use the range on this page only as a range. Confirm with a local station and the product label.
Don’t do this first
- Don’t treat the IOU as a yield doubling; don’t sow thick under long straw with no N.
Rate range
Add nitrogen
A few kg urea per mu, by how much straw
Follow the local agronomist, and watch nitrogen steal.
Chop length
As short and even as you can
Don’t leave it in heaps.
These are ranges. Confirm with your local extension station and the product label.
When you see After straw return, test. Take soil from the bad patch and from a greener neighbour, separately.
Lesson video
2026-03-11 · Li Zeyu · For learning. Serious damage: local agronomist or a soil test.
For learning only. Fertiliser and pesticide decisions need a local agronomist and a soil test.
Not sure? Photograph the field to identify the problem