Lieu-dit · Sézanne
Les Gros Seins
Les Gros Seins is a lieu-dit in Sézanne, Côte de Sézanne, Champagne, whose largest tier is champagne.
2.47 ha
delimited
171 m
elevation
10.3 h
sun at harvest
Open on the mapWith the boundary, the plots, the sun through the year and the bedrock.
In figures
| Level | Champagneinao-aoc-viticoles-bulk (not in this commune) |
|---|---|
| Village | Sézanne |
| Region | Côte de Sézanne, Champagne |
| Delimited | 2.47 hainao-aoc-viticoles-bulk (not in this commune) · cadastre-etalab (4 September 2026) |
| Planted | 2.18 hacadastre-etalab (4 September 2026) · ign-bdtopo-vigne (4 September 2026) · ign-rpg-2024 (5 September 2026) |
| Parcels | 16 |
| Grape variety | chardonnay 78 %, pinot noir 15 %, meunier 7 % also permitted: arbane, petit meslier, pinot blanc, pinot grisinao-cahiers-des-charges (7 September 2026) · dgddi-superficies-produits (7 September 2026) · franceagrimer-observatoire-viticulture (7 September 2026) |
| Organic | 46%agence-bio-cartobio (c. 5 September 2026) · agence-bio-operateurs (5 September 2026) |
Place in the village
Among the 46 named plots ranked champagne in Sézanne, from high to low:
Position
171 m
elevation
15.9%
steep
ESE
east-southeast
upper
even slope
| Elevation | 171 m 159 to 187 mign-rge-alti (5 September 2026) |
|---|---|
| Daytime temperature | −0.07 °C by day, relative to the village centre at 162 m, ± 0.07 °Cmeteo-france-quotidiennes (6 September 2026) · meteo-france-postes (6 September 2026) · meteo-france-lsh (6 September 2026) · ign-rge-alti (5 September 2026) |
| Slope | 15.9% 9.0°ign-rge-alti (5 September 2026) |
| Aspect | east-southeast 110°ign-rge-alti (5 September 2026) |
| On the slope | 59% upper slope, on an even plane, 297 m drains onto itign-rge-alti (5 September 2026) |
Bedrock
- 99%Ypresian sand, sandstone and plastic clay 56–48 million years
In the glass. There is no clear picture. This subsoil says little as long as it is not known whether the parcel stands on the clay or on the sand. (weak indication)
The lowest Tertiary fill of the Paris Basin: variegated, often kaolinite-rich clay with sand layers and cemented sandstone beds within it, locally with lignite remains. Deposited in river deltas, marshes and lagoons under a warm and humid climate. Lower Eocene, Ypresian, roughly 56 to 48 million years.
For the vine. This is a mixture, and that determines its behaviour: the plastic clay is almost impermeable, swells in wet weather and cracks in drought, while water simply runs away through the sand. Where clay dominates the ground stays cold and wet in spring and rooting stays shallow; where sand dominates the picture is reversed. The soils are poor in lime to lime-free, so chlorosis is not an issue here.
BRGM geological map at 1:50,000. It tells vineyards apart, not plots within a vineyard. The link between rock and taste is indirect: soil depth, water and warmth do the work, and slope, vine age and the cellar do the rest. Units on that map: e4.
brgm-bdcharm50 (4 September 2026)Sun and horizon
07:30
above the flat horizon
17:45
behind the hill
10.3 h
sun at harvest
1.2 h
lost to the hill
Grey: sun up, but behind the hill or the vineyard's own slope.
Around harvest the sun rises here at 07:30 above the flat horizon and disappears at 17:45 behind the hill: 10.3 hours of direct sun on a clear day. The ridge reaches 23.8° above the horizon to the west. The relief costs 1.5% of the irradiation from April to October, direct and diffuse together.
| Irradiation | −0.7% versus flat land 1,016 kWh/m² from April to October, 44% of it diffuseunder the average cloudiness of 2005 to 2023 (PVGIS-SARAH3, EU JRC); direct, diffuse and reflected light togetherign-rge-alti (5 September 2026) · ign-lidarhd-mnh (6 September 2026) · ign-bdforet-v2 (5 September 2026) · jrc-pvgis-sarah3 (10 September 2026) |
|---|---|
| Open sky | 97.2% of the sky the slope itself sees; the surrounding relief blocks the restign-rge-alti (5 September 2026) · ign-lidarhd-mnh (6 September 2026) · ign-bdforet-v2 (5 September 2026) |
Three reference days and the caveat
| rise | set | sun | day | |
|---|---|---|---|---|
| 21 June | 06:02 | 19:21 | 13.3 h | 16.2 h |
| 20 September | 07:30 | 17:45 | 10.3 h | 12.3 h |
| 21 December | 08:37 | 14:59 | 6.4 h | 8.3 h |
Computed from the IGN elevation model at 5 m: horizon in 36 directions up to six kilometres, sun position per minute, angle of incidence on the mean slope. Clear sky, with the tree canopy from the IGN forest inventory as a raised horizon (15 m closed forest, 5 m heath, trees within 60 m ignored), 27% of the far field is forest (BD Forêt), no buildings.
The irradiation loss does include clouds: the average of 2005 to 2023 (PVGIS-SARAH3, EU JRC), not any particular year.
Air and cold
28 m
above the lowest point
drains far away
cold air
little inflow
1.7 ha flows past
| Cold air | 28 m high on the slope, cold air drains far awayign-rge-alti (5 September 2026) |
|---|---|
| Cold air passing through | 1.7 ha little inflow, mean over the polygon 0.28 haign-rge-alti (5 September 2026) |
Planting
NE-SW
across the slope
1.15 m
between the rows
94%
vineyard in 1950
| Rows | NE-SW (45°) across the slope (64°), every 1.15 m, varies by plotmeasured over 2.1 of 2.2 ha plantedign-bdortho (6 September 2026) |
|---|---|
| Vineyard in 1950 | 94% planted since: 0.12 ha, rows then ran 21° differentlyassessed over 1.9 ha on the 1950-1965 aerial photographign-photos-historiques-1950-1965 (6 September 2026) |
Climate over time
station ROMILLY, 77 m, 24.8 km away
growing season, April to October: 1951-1980: 14.2 °C, 1991-2020: 15.4 °C
Huglin index: 1951-1980: 1,542, 1991-2020: 1,773
last spring frost: 1951-1980: day 124, 1991-2020: day 115
series homogenised through 2022
The name
- grand
- large, usually relative to a smaller plot with the same name. Shape and position · Terroirium, Eigen telling over de namen in deze atlas (2026)
This is about the words, not about this plot: the same name can have arisen differently elsewhere.
Who owns land here
No parcel here is registered to a legal entity. In France only those owners are public; parcels of private individuals are not.
Nearby lieux-dits
- Montgevreux Champagne · 150 m
- Le Val aux Moines Champagne · 250 m
- Les Croix Champagne · 300 m
- Les Chevaux Champagne · 300 m
- Vadonval Champagne · 350 m
- Les Cochues Champagne · 500 m
- Les Sablons Champagne · 500 m
- La Guette Champagne · 550 m
In the same village, measured between label points. That does not say which ones border each other; the map shows that.
Where each figure comes from
- Classification
- The INAO delimitation per denomination, cut against the cadastral parcel. Only the INAO's own plans are legally binding; this map is informational.
- Area
- Computed on the sphere from longitude and latitude (turf.area), not in Lambert-93. For an appellation this is the union of the INAO polygons across commune boundaries, measured on the unclosed geometry; the fifteen metres used to close the outline for the map are not counted. For a climat it is the union of the cadastral lieu-dit polygons with that name.
- Planted
- Parcel area times vineyard cover, where cover comes from the IGN vegetation layer supplemented by the agricultural declaration. Checked against the customs harvest declarations: median deviation 5.1 per cent over a hundred appellations.
- Elevation
- Mean of the elevation-model cells whose centre falls inside the polygon, on a 5 m grid.
- Slope
- Per-cell slope from the elevation model using Horn's method, then averaged over the cells in the polygon.
- Aspect
- Vector mean of the per-cell aspect. A plain average would turn north-east and north-west into south.
- Sun at harvest
- Hours of direct sun on 20 September under a clear sky, with the horizon in 36 directions out to six kilometres and the height of woods and buildings on top of it. Canopy height is measured where LiDAR HD covers the area and estimated from BD Forêt where it does not; the panel states which of the two was used.
- Grape variety by appellation
- Per appellation and colour the permitted varieties from the approved cahier des charges; per appellation and tier the declared hectares of white and red from the customs harvest declaration (product codes). One colour permitted: the main variety of that colour. Two colours: from 85 percent of the hectares that colour applies, in between it is called mixed. Champagne: the dominant variety from the planted hectares per variety per commune from FranceAgriMer. Per polygon the dominant variety of its parts by area. Derived, not measured: the variety per plot exists only in the customs vineyard register, which is not public. In a two-colour appellation a single plot may carry the other variety. Customs withhold small appellations (statistical secrecy), in which case the split is missing.
- Bedrock
- The geological unit covering the largest share of the polygon, from the 1:50,000 geological map. At 1:50,000 the map separates one climat from another, but not what varies inside a climat.
- Organic
- Share of the area certified organic or in conversion, from the CartoBio plot register.