WSET DIPLOMA D1 EXAM QUESTIONS
AND ANSWERS 2025
Most important North American grape species - Correct Ans-Vitis labrusca, Vitis riparia,
Vitis berlandieri and Vitis rupestris
Four main sections of a grape vine - Correct Ans-the main shoots, one-year-old wood,
permanent wood and the roots
What comprises the canopy of a vine? - Correct Ans-The main shoots and all of their
major structures - stem, buds, leaves, lateral shoots, tendrils and inflorescences/grape
bunches
What do the main shoots grow from, and when? - Correct Ans-The main shoots on the
vine grow in spring from buds retained from the previous year
Where are carbohydrates stored in a vine? - Correct Ans-Stems, trunks, roots
Define lignify - Correct Ans-Green shoots become woody and rigid, they are then called
canes
Where do buds form? - Correct Ans-between the leaf stalk (petiole) and the stem
Define the two types of buds - Correct Ans-- Compound buds (form in one growing
season and break open the following growing season, producing main shoots; typically a
primary, secondary, and maybe tertiary)- Prompt buds (form and break open same
season, form lateral shoots)
- Prompt buds (form and break open same season, form lateral shoots)
1|Page
,WSET
What is the main function of lateral shoots? When are they desirable/undesirable? -
Correct Ans-- to allow the plant to carry on growing if the tip of the main shoot has been
damaged or eaten
- can provide an additional source of leaves for photosynthesis (useful if the laterals are
near the ends of the main shoots)
What is second crop? - Correct Ans-Lateral shoots often produce inflorescences, which
can be known as a 'second crop'
- Growth of laterals nearer the base of the main shoot can be undesirable as they
impede air flow and can shade the fruit too much
What is green harvesting? - Correct Ans-Removal of second crop during summer
Define one-year-old wood - Correct Ans-the main shoots from the last growing season
that were kept at pruning, supports compound buds; cane or spur
Define permanent wood - Correct Ans-woody parts of the vine that are older than one
year, including the trunk
where are most roots found? - Correct Ans-top 50cm of soil
what distinguishes PN clone 115? - Correct Ans-low yield, small grapes, good for high
quality of red wines
what distinguishes PN clone 521? - Correct Ans-high yield, bigger grapes, good for
sparkling wine production
When is leaf fall and dormancy? - Correct Ans-Nov-March
2|Page
,WSET
When is budburst? - Correct Ans-March-April
When is shoot and leaf growth? - Correct Ans-March-July
When is flowering and fruit set? - Correct Ans-May-June
When is grape development? - Correct Ans-June-Oct
When is harvest? - Correct Ans-Sept-Oct
How does the vine support itself during dormancy? - Correct Ans-starch in the roots,
trunk, and branches
Below what temp can vines be severly damaged? die? - Correct Ans--15C, -25C
What factors determine the timing of budburst? - Correct Ans-- air temp (>10C)
- soil temp (higher encourages earlier budburst)
- variety
- human factors (e.g. winter pruning late -> later budburst)
Why is high continentality good for budburst? - Correct Ans-marked differences in temp
can result in uniform budburst
what determines the vigor of a vine? - Correct Ans-rate of shoot growth
3|Page
, WSET
when does the fastest rate of shoot growth typically occur? - Correct Ans-between
budburst and flowering
what could cause low carb levels in roots, trunk, and branches? - Correct Ans-- excessive
leaf removal
- water stress
- high crop loads in prev season
what can slow initial shoot growth rates? - Correct Ans-low carb levels
what supports shoot growth in later stages? - Correct Ans-photosynthesis
at what point of the vine growing cycle is water stress not desired? - Correct Ans-late
stages of shoot growth (can affect photosynthesis)
what can stunted shoot growth lead to? - Correct Ans-- weak shoots
- reduction in leaf number/smaller leaves
- inflorescences that do not flower properly
what can limit bud fruitfulness? - Correct Ans-- low temp (<25C)
- water stress
- shading
- nutrient deficiency
how long after budburst does flowering typically take place? - Correct Ans-8 weeks
(temp dependent)
4|Page