# BBCH-scale (weed)

The BBCH-scale (weed) identifies the phenological development stages of weed species. It is a plant species specific version of the BBCH-scale.
D = Dicotyledons G = Gramineae M = Monocotyledons P = Perennial plants V = Development from vegetative parts or propagated organs No code letter is used if the description applies to all groups of plants.
Phenological growth stages and BBCH-identification keys of weeds :
| Code | Plant type | Description |
| Principal growth stage 0: Germination, sprouting, bud development |||
| 00 | | Dry seed |
| | V | Perennating or reproductive organs during the resting period (tuber, rhizome, bulb, stolon) |
| | P | Winter dormancy or resting period |
| 01 | | Beginning of seed imbibition |
| | P, V | Beginning of bud swelling |
| 03 | | Seed imbibition complete |
| | P, V | End of bud swelling |
| 05 | | Radicle (root) emerged from seed |
| | V | Perennating or reproductive organs forming roots |
| 06 | | Elongation of radicle, formation of root hairs and/or lateral roots |
| 07 | G | Coleoptile emerged from caryopsis |
| | D, M | Hypocotyl with cotyledons or shoot breaking through seed coat |
| | P, V | Beginning of sprouting or bud breaking |
| 08 | D | Hypocotyl with cotyledons or shoot growing towards soil surface |
| | V | Shoot growing towards soil surface |
| 09 | G | Emergence: Coleoptile breaks through soil surface |
| | D, M | Emergence: Cotyledons break through soil surface (except hypogeal germination); |
| | V | Emergence: Shoot/Leaf breaks through soil surface |
| | P | Buds show green tips |
| Principal growth stage 1: Leaf development (main shoot) |||
| 10 | G, M | First true leaf emerged from coleoptile |
| | D | Cotyledons completely unfolded |
| | P | First leaves separated |
| 11 | | First true leaf, leaf pair or whorl unfolded |
| | P | First leaves unfolded |
| 12 | | 2 true leaves, leaf pairs or whorls unfolded |
| 13 | | 3 true leaves, leaf pairs or whorls unfolded |
| 1 . | | Stages continuous till ... |
| 19 | | 9 or more true leaves, leaf pairs or whorls unfolded |
| Principal growth stage 2: Formation of side shoots / tillering |||
| 21 | | First side shoot visible |
| | G | First tiller visible |
| 22 | | 2 side shoots visible |
| | G | 2 tillers visible |
| 23 | | 3 side shoots visible |
| | G | 3 tillers visible |
| 2 . | | Stages continuous till ... |
| 29 | | 9 or more side shoots visible |
| | G | 9 or more tillers visible |
| Principal growth stage 3: Stem elongation /shoot development (main shoot) |||
| 30 | | Beginning of stem elongation |
| | G | Beginning of shooting |
| 31 | | 1 visibly extended internode |
| | G | 1 node stage |
| 32 | | 2 visibly extended internode; |
| | G | 2 node stage |
| 33 | | 3 visibly extended internode |
| | G | 3 node stage |
| 3 . | | Stages continuous till ... |
| 39 | | 9 or more visibly extended internodes |
| | G | 9 or more nodes |
| Principal growth stage 4: vegetative propagation / booting (main shoot) |||
| 40 | V | Vegetative reproductive organs begin to develop (rhizomes, stolons, tubers, runners, bulbs) |
| 41 | G | Flag leaf sheath extending |
| 42 | V | First young plant visible |
| 43 | G | Flag leaf sheath just visibly swollen (mid-boot) |
| 45 | G | Flag leaf sheath swollen (late-boot) |
| 47 | G | Flag leaf sheath opening |
| 49 | V | Constant new development of young plants; vegetative reproductive organs reach final size |
| | G | First awns visible |
| Principal growth stage 5: Inflorescence emergence (main shoot) / heading |||
| 51 | | Inflorescence or flower buds visible |
| | G | Beginning of heading |
| 55 | | First individual flowers visible (still closed) |
| | G | Half of inflorescence emerged (middle of heading) |
| 59 | | First flower petals visible (in petalled forms) |
| | G | Inflorescence fully emerged (end of heading) |
| Principal growth stage 6: Flowering (main shoot) |||
| 60 | | First flowers open (sporadically) |
| 61 | | Beginning of flowering: 10% of flowers open |
| 63 | | 30% of flowers open |
| 65 | | Full flowering: 50% of flowers open, first petals may be fallen |
| 67 | | Flowering finishing: majority of petals fallen or dry |
| 69 | | End of flowering: fruit set visible |
| Principal growth stage 7: Development of fruit |||
| 71 | | Fruits begin to develop |
| | G | Caryopsis watery ripe |
| 79 | | Nearly all fruits have reached final size normal for the species and location |
| Principal growth stage 8: Ripening or maturity of fruit and seed |||
| 81 | | Beginning of ripening or fruit coloration |
| 89 | | Fully ripe |
| Principal growth stage 9: Senescence, beginning of dormancy |||
| 97 | | End of leaf fall, plants or above ground parts dead or dormant; |
| | P, V | Plant resting or dormant |