SLATE
SOILS ARE DEBRIS SOILS. The
landscape is dominated by the grey colour of the weathered
grey-blue
Hunsrück slates.
The dark-brown, humus-rich topsoil is often covered by
slate debris and rubble. The spaces between the loose materials
are well aerated. The rock cover protects the soil from
desiccation. The soil contains loess as well as clay and
mineral-rich fine earth derived from weathered slate. The
plants are well supplied with minerals such as potassium,
magnesium, sodium and iron contained in the clay fraction.
The slate weathers rapidly, thus ensuring a continuous
supply of nutrients and micronutrients.
The
presence of slate debris enhances permeability and produces a loosely
structured soil. Rainwater can easily permeate into the
subsoil. The stone content increases with depth, which reduces
the soil water capacity. This can result in water stress in the
summer months. Consequently, the vine must tap into additional
reserves by sending roots deep into the debris subsoil. Not even
solid rock can stop the roots and some will grow along joints to
penetrate deep into the bedrock. Is this the secret behind the
distinctive minerality of the slate wines?
THE ROCK
Slate, also known as Hunsrück slate, is typically
found beneath the vineyards between Lorch and Lorchhausen.
The dark grey to blue grey colour of this lithified
marine clay sediment is due to the presence of
bituminous organic substances.
On first sight the stony slate slopes appear to
be a poor location for growing wine. However, these
soils are rich in base nutrients and provide excellent
ripening conditions. Slate weathers quickly to
produce fertile earth and large amounts of mineral
nutrients. Slate debris also protects the soil
from erosion and improves soil
SLATE
Hortic
anthrosol form- ed on slate debris. A
decalcified, mineral- rich, warm location with good ripening
conditions.
Slate
soils – warm
and dry.
Slate stones are quick to warm and store heat during the
daytime. This heat is given off in the evenings or when clouds
obscure the sun. The warm soil and vineyard microclimate
promotes the growth and ripening process.
SOIL
PROPERTIES
low
water capacity
moderate
rootability
very
good aeration
very
good warming capacity
Calcium
carbonate free
Large
mineral nutrient potential
structure
therefore increasing the permeability for air and water.
In some locations the soil properties and ripening
conditions are further improved by the presence
of loess.