What are the 2 main species of vine?
1. Vitis vinifera
2. North American Vines (3 chief species):
- Vitis labrusca
- Vitis riparia
- Vitis rupestris
What is phylloxera?
- A fungal disease
- A viral disease
- A North American root louse
A North American root louse.
Of the two main vine species, which one is more resistant to phylloxera?
How does it protect itself?
North American vine species are more resistant to phylloxera. It is for this reason American rootstocks are widely used across the world.
The North American vine protects itself from phylloxera by seeping a sticky sap that inhibits the louse from eating, and the vine generates a defensive layer behind a wound which prevents the louse from damaging the plant material further.
Are there any places in the world today that remain free of phylloxera?
Yes, the major ones are:
- Canary Islands
- Some areas in South Australia and Argentina
Of the two main vine species, which is the most widely used around the world for quality wine production?
Vitis vinifera is most used for fine wine grape growing in the world.
The grape varieties we all know by name are from the Vitis vinifera family, such as Sauvignon Blanc, Chardonnay, Pinot Noir, Zinfandel, Syrah, and Cabernet Sauvignon.
What are some primary differences between Vitis vinifera and North American vines in terms of winemaking?
- known to have more desirable aromas for wine
- considered to produce higher-quality grapes for the production of fine wine
North American vines:
- more resistant to pests and diseases than vinifera
- generally better suited to extreme climates than vinifera
What are 2 different ways a vine can be propagated?
Cutting - when a section of a shoot is cut off from an existing vine and is planted in order to grow a brand new plant. It's done mostly in nurseries;
Layering: A vine's 1 year-old cane is bent into the ground and partially buried with the tip of the cane poking out above ground; the buried part grows roots and establishes itself as a new plant. It takes place in the vineyard.
What is clonal selection?
When a vine naturally mutates and its new, positive characteristics are propogated by cutting or layering.
Grafting is a procedure used to fuse budwood of a desired variety (usually V. vinifera) onto another rootstock (usually a North American vine).
This technique was discovered to be both useful and necessary after phylloxera decimated European vineyards in the mid-to-late 1800s. The idea is to have a phylloxera-resistant vine that produces V. vinifera.
What are some of the benefits of grafting onto American rootstocks?
- American rootstock protects against phylloxera while giving ability to produce V. vinifera grapes;
- North American rootstocks are found to be resistant to nematodes, drought, and alkaline soils, unlike V. vinifera.
What is head grafting and why is it used?
Head grafting is when a vine's top, or head, is cut off its trunk and the cutting of a new variety is grafted on to the trunk where the old head was.
The purpose of head grafting is to switch out grape varieties instead of uprooting and replanting an entire vineyard. Head grafting will produce fruit the year after the grafting, and it's a lot less expensive than replanting an entire vineyard with the added bonus of keeping the established trunk and roots.
Name 3 different ways to create new grape varieties.
What is cross-fertilization?
Name a few reasons why a viticulturist might want to cross-fertilize.
Cross-fertilization is when a viticulturist takes the pollen from the male part of one vine's flowers and fertilizes the female parts of a different vine's flowers to create a new grape variety.
The cross-fertilized flowers will grow into grapes, which will have seeds. Those seeds are collected, later planted, and if those seeds grow into a viable plant, a new grape variety is born.
Reasons to cross-fertilize:
- To create a disease resistant variety;
- To adapt the new grape to climate extremes or drought;
- To increase quality or yields.
What is the difference between crossings and hybrids?
Crossings: when a new grape variety is created by crossing parents of the same vine species, e.g. Cabernet Sauvignon (Sauvignon Blanc x Cabernet Franc - both V. vinifera).
Hybrids: when at least two different vine species, usually a North American vine and a vinifera vine, are crossed to create a brand new vine species, e.g. Concord and Vidal Blanc (only 1 parent is V. vinifera).
What is the crossing of Cabernet Sauvignon?
Cabernet Franc x Sauvignon Blanc
What is the crossing of Müller-Thurgau?
Riesling x Madeleine Royale
What is the crossing of Pinotage?
Cinsault x Pinot Noir
What are the 4 main parts of a vine?
- Permanent wood
- 1 year-old wood
- Green parts (also known as the canopy: leaves, grapes, tendrils, etc.)
Explain the importance of a vine's leaves.
Leaves are what drive the plant's growth.
Via photosynthesis, leaves use sunshine to convert water and CO2 into the things it needs to grow: glucose and oxygen.
What is transpiration?
Transpiration is the process of how water is absorbed by a vine's roots, transported throughout the plant, and out of its leaves in vapor form.
The warmer the climate, the faster water evaporates from the leaves, which means the vine needs more water from the soil.
To get really nerdy, read more about transpiration here.
What are tendrils on a vine and what is their role?
Tendrils are a vine's support system so that it stays upright (or attached to a trellising system).
What are the buds on a vine?
Where are they found?
Buds contain and will become the following year's green parts (tendrils, flowers, leaves, shoot).
Buds are primordial shoots found between a shoot and a leaf.
What is 1-year-old wood (aka a cane)?
The previous year's shoot
The buds on last year's shoot will be the 1-year-old wood's shoots, tendrils, and leaves.
What is permanent wood on a vine?
Wood that is more than 1 year old:
- arms / cordons (if there)
What are the functions of a vine's roots?
Absorb water + nutrients which they send up the plant
Anchor the vine in the soil
Store carbohydrates over winter to keep the vine alive
What are the "reproductive organs" of a vine?
Flowers have both male and female parts, and vines' flowers self-pollinate. Each pollinated flower then turns into a grape.
What is inflorescence?
Clusters of flowers (before they actually become flowers).
Inflorescences will eventually become flowers which then transform into grape clusters.
Photo courtesy of Patty Skinkis, Oregon State University.
What is the difference between a cane and spur?
They're both 1 year-old wood from the previous year's growth. However, the main difference between them is how many buds each has.
Cane: a long woody branch with 8 to 20 buds
Spur: a short woody branch with only 2 to 3 buds
What are some important factors to consider when deciding where to establish a new vineyard?
1. Environmental/Climate considerations
- location and aspect of proposed vineyard
- soil type/fertility, drainage, average sunlight/rain, temperature
2. Trade/Business considerations
- how remote is the vineyard?
- how easy will it be to find employees or help at harvest?
3. Which grape(s) to plant?
- which varieties suit the climate?
- is there demand for the grape(s)?
- any legal restrictions?
What are the 2 main types of vine training?