A two-digit number that changes the illustrations.
The crop growth stage is entered by whoever is in the field, cached for twenty-four hours, and it does two things: it decides which stage the crop and beast illustrations are drawn at, and it sets the status shown on every Plotting page.
The feed.
Source
- Entered by
- Whoever walked the field, through an ops entry
- Not
- A satellite, a model or an APIThere is no feed that knows this better than somebody standing in the crop
- TTL
- 24 hours
- Scale
- BBCHThe standard two-digit growth-stage scale used across European arable
What it changes
- Crop illustration stage
- Bare drill, emerging, tillering, in ear, ripe, stubble
- Beast mark
- The barley and seedling marks are drawn at the matching stage
- Plotting status
- In the ground · Growing · Nearly there · Harvested · Next season
- Nothing else
- No price, no availability, no delivery date
Without it
- Falls back to
- The seasonal default stage for the current season
- Which is
- Right within a fortnight or so, most years
- And is
- Entirely good enough for an illustration
BBCH, and what the site does with it.
| BBCH | What it means | Illustration stage | Plotting status |
|---|---|---|---|
| 00–09 | Germination | Bare drill, dark earth | In the ground |
| 10–19 | Leaf development | First green through the tramlines | In the ground |
| 21–29 | Tillering | A green sheet, no height | Growing |
| 30–39 | Stem extension, first node to flag leaf | Standing, still green | Growing |
| 51–59 | Ear emergence | Ears out, awns showing | Growing |
| 61–69 | Flowering | Ears out, anthers visible | Growing |
| 71–77 | Grain fill, milk stage | Green going gold | Nearly there |
| 83–87 | Dough stage | Gold, heads heavy | Nearly there |
| 89–92 | Ripe to harvest ready | Full gold, standing still | Nearly there |
| — | Combined | Stubble, then ploughed | Harvested |
What the stage does to the plots.
Every plot page shows a status rather than a date, and that status comes from this feed. The map is schematic on purpose.
- A Quarter Acre of Barley Spring barley · Quarter acre BBCH 30
- A Wheat Run Winter wheat · A run BBCH 87
- A Potato Bed Potatoes · One bed Lifting
- A Strip of Oilseed Rape Oilseed rape · One strip Harvested Taken
- Twenty Metres of Hedgerow Nature units · 20 metres Laid
- A Wildflower Plot Out of production · One plot In flower
A plot is a marketing device attached to a forward sale, never a demised parcel of land, which is why this plan is deliberately not survey-accurate.
One field of winter wheat, in stages.
Drilled deliberately late to give the blackgrass less of a chance. The plate is bare earth and tramlines.
Two leaves through. The site shows the first green.
Tillering, and doing very little. This is the state most of the winter.
First node detectable. It starts moving quickly from here.
Flag leaf out, which is the spray that pays for itself.
Flowering. The plate is green and the ears are out.
Dough stage. Green going gold, and everybody starts watching the forecast.
Harvest ripe. Plotting flips to Harvested the day the combine goes in.
Why a person enters this rather than a satellite.
There are perfectly good remote-sensing products that will estimate a growth stage from orbit, and for a thousand hectares they are the right answer.
For this site they are the wrong answer, because the value of the number is not its accuracy. It is that somebody walked into the crop, looked at it, and typed what they saw. A twenty-four hour cache on a human observation is more honest than a fifteen-minute cache on a model, and it is considerably cheaper.
It also means the failure mode is a person being busy, which is a failure mode everybody understands and nobody needs an incident report about.
Entered by a person
Not modelled, not sensed.
Twenty-four hours
A stage that changed hourly would be an error.
Drives Plotting
Status on every plot page.
Falls back
To the seasonal default stage.
The plots themselves.
Six pieces of ground, a fixed price, and produce delivered in kind.
